Snell Lower Limb

5

CHAPTER

Lower Limb

The primary func tion of the lower limb is to suppo rt the weight of walk the boing, dy and to provide a stable f oun standing, or running. E ach lower li mbdation may whe b e d nivided into the gluteal region, the thigh, the knee , the leg, the ankle, and the foot. It is suggested that the lower limb be reviewed in the following order: 1. A brief overview of the bo nes an d the m ajor joints, preferably with use o f an articulated skeleton. 2. A considerat ion of the more important muscl es, concentrating on their actions and their nerve supply. 3. A brief review of t he b lood supply and the lymphatic drainage. 4. A detailed overvi ew of the n erves and their dist ribution.

shaped area and is covered with hyaline cartilage. The

ac -

etabular fossa floor of the acetabulum, which nonarticular. The is the acetabular notch is situated on isthe inferior margi n of the ac etabu lum. The iliac crest runs between the anterior and posterior superior iliac spines. Below these spines are the corresponding inferior iliac spines. The ischium po ssesse s an ischial spine and an ischial tuberosity (Fig. 5-1). The pubis has a body and a superior and an inferior pubic rami. The b ody of the p ubis has the pubic crest an d the pubic tubercle, and it articulates with the pubic bone of the oppo site side at the symphysis pubis. The obturator foramen is a large opening that is bo un de d b y the p arts o f the isch ium an d p ub is (Fig. 5-1).

To assist students, tables are used extensively in this chapter.

Bones o f the Thigh

BONES

The b one s of the thigh co nsist of the f emu r and the pa tella (Fig. 5-2).

Bones o f the Pelvic Gir dle The pelvic girdle con sists of four b one s: the two hip b one s, the sacrum, and the coccyx (see Fig. 3-1). The pelvic girdle pro vide s a stron g co nn ec tion be twe en the trun k an d the lower limbs.

FEMUR

In ch ildren, ea ch h ip bon e co nsists of the ilium, the ischium , and the pub is (Fig. 5-1). At pub erty, these three bon es fuse together to form on e large, irr egular bon e. The acetabulum

The head of the femur is hemisphe ric in sha pe and fits into the acetabulum to form the hip joint. The fovea capitis is a small depression in the center of the head for the attachment of the ligament of the head. Part of the blood supply to the he ad of the femu r from the ob tura tor arte ry is conveyed along this ligament and enters the bone at the fovea. The neck connects the head to the shaft (Fig. 5-2). The greater and the lesse r t rochantersare larg e e minences at

is a cup-shaped depression on the outer surface of the hip bo ne , a nd it a rticu late s with the he ad of th e femu r. The articular surface of the acetabulum is limited to a horseshoe-

the junction of the neck and the shaft. Connecting the two trochanters are the intertrochanteric line anteriorly (where the iliofemoral ligament is attached) and a promi-

HIP BONE

15 7

15 8 CHAPTER 5 Lower Limb

rough surface for attachment of inteross eous ligament

iliac crest iliac fossa

posterior superior iliac spine anterior superior iliac spine

auricular surface

anterior inferior iliac spine

posterior inferior iliac spine greater sciatic notch

iliopectineal line superior ramus of pubis

ischial spine lesser s ciatic notch

body of pubis pubic tubercle

obturator membrane

pubic crest obturator canal

ischial tuberosity

inferior ramus of pubis

ischial ramus

A

tubercle of ilium

ilium

acetabulum line of fusion of bones obturator foramen ischium pubis B Figure 5-1 Right h ip bone . A. Medial surface. the il ium, the ischi um , and the pub is.

B. Lateral surface. Note the

lines of f usion b etwee n

CHAPTER 5

Lower Limb

15 9

for attachment of rectus femoris head

greater trochanter

for attachment of vastus lateralis

fovea capitis

neck

for attachment of vastus medialis

patella

intertrochanteric line lesser trochanter for attachment of ligamentum patellae B

shaft intercondylar eminence lateral condyle

medial condyle

head of fibula tibial tuberosity adductor tubercle neck lateral condyle A

medial epicondyle medial condyle

anterior border lateral border

patellar surface

shaft of tibia shaft

medial malleolus lateral malleolus C Figure 5-2 A. Anteri or su rface of the right femu Anterior surface o

r. B. Anterior surface of the right patella.

C.

f the righ t tibia an d fi bu la.

nent intertr ochanteric crestpo sterio rly ( on whic h is th e quadrat e tubercle). The shaft is smooth on its anterior surface but has a ridge posteriorl y (the linea aspera ) to which are attached muscles and intermuscular septa. The medial margin of the linea aspera continues below (as the medial supracondylar ridge ) to the adductor tubercle (Fig. 5-2) on the medial condyle. The lateral margin becomes continuous below with the lateral supra condy lar ridge.On the

maximus muscle. A flat, triangular area on the posterior surface of the lower end of the shaft i s called the popliteal surface. The lower end of the femur has a lateral and a medial condyle, which are separated posteriorly by the intercondylar notch. The anterior surf ace s of the con dyles are join ed b y an ar tic ula r su rfac e for th e p at ella. The two con dyles take p art in the formation of the kne e joint. Above the condyles are the medial and the lateral epicondyles.

po sterio r surfactuberosity e of the shafor ft bthe elo w the grea ha nte r is the gluteal insertion ofter thetroc gluteus

The adductor tubercle is continuous with the medial epicondyle.


face for articula tion with the latera l cond yle of the tibia. The shaft is attache d to the tibia by the interosseous memb rane. The lower end of the fibula forms the lateral malleolus.

CLINICAL NOTES BLOOD SUPPLY TO THE FEMORALHEAD FRACTURES OF THEFEMORALNECK

AND

In the young, the epiph ysis of the he ad is supp lied by a sma ll branch o f the obturator artery, w hich p asses to the along thenec ligament the femoral head. The upphead er part of the k of thetofemur rece ives a profuse b loo d su pp ly from th e med ia l fem o ra l c irc um flex artery . In the adu lt, after the epiphyseal c artilage disappears, an anastomosis between the two sources of blo od sup ply is esta blish ed . Frac ture s o f the femo ral neck interfere with or completely interrupt the main blo od sup ply from th e ro ot o f the fem ora l ne ck to the femo ral head . Avascular necrosis of t he femo ral head is a co mmo n com plication of femo ral neck fr actures.

CLINICAL NOTES FRACTURES

OF THENECK OF THE FIBULA AND

INJURY TO THE COMMON P ERONEALNERVE The common peroneal nerve is in an exposed position as it winds around the neck of the fibula. The nerve can be injured in fractures of the neck of the fibula an d b y pressur e from c asts or spli nts.

Bones o f the Foo t The bones of the foot are the tarsal bones, the metatarsal bo ne s, an d th e p ha lan ges ( Fig. 5-3).

PATELL A The pa tella is the largest sesamoid bo ne ( a bo ne that de velops within a tendon), and it lies within the tendon of the quadriceps femoris muscle in front of the knee joint. It is triangular in shap e. Its ape x lies inferiorly and is conne cted to the tub erosity of the tibia b y the lig ame ntum patellae. T he po sterio r surfac e a rticu late s with the co nd yles of the femu r.

Bones of the L eg The bon es of the leg a re the tibia a nd the fibula ( Fig. 5-2).

TIBIA The tibia is the large, weight- be aring, med ial bon e of the leg. At the upper end are the lateral and medial condyles, which articulate wit h the lateral and med ial condyles of the femur with the lateral and medial menisci intervening. Sepa rating t he upp er articular surf ace s of the tibial cond yles is the inter condylar e minence.The lateral condyle pos-

TARSAL BONES The tarsal bone s are the calca neu m, the talus, t he n avicular, the cuboid, and the three cuneif orm bones.

Calcaneum The calca neu m is the largest bone of the foot. I t articulates abo ve with the talus and in front wi th the cu boid b one . The po ste rior surfa ce form s th e pro min en ce of th e he el, an d the med ial s urface possess es a large, shelf like ridge (the sustentaculum tali) that assists in supporting of the talus.

Talus The talus arti culates ab ove at the ankle joint wi th the tibia and the fibula, be low with the calca neu m, and in front wit h the n avicular b on e ( Fig. 5-3). It posse sses a head, neck, an d body. Nume rou s imp orta nt ligame nts are atta ch ed to the talus, but no muscles are attached to this bone.

sesses an o val art icular fa cet for the h ead of the fibula on its lateral aspect. At the up per en d o f the a nterior border of the shaft of the tibia is the tuberosity (Fig. 5-2), which receives the attachmen t of the ligame ntum p atellae. T he a nterior border is prolonged downward and medially to form the medial malleolus b e low . The la te ra l b or d er of th e tib ia pro vide s attachment to the inteross eous me mbrane, which b inds together the tibia and the fibula. The lower end of the tibia shows a wide, rough dep ression on its lateral surf ace for articulati on with the fibula.

Navicular

FIBULA

Cuneiform Bones

The fibula provides attach men t for mu scles. It takes no pa rt in articulation at the knee joint, but below, it forms part of

The three cuneiform bones are small, wedge-shaped bones that articulate proximally with the navicular bone and dis-

the an kle joint. The head forms the upper end of the fibula (Fig. 5-2). It has a styloid process, and it possesses an articular sur-

tally with the first three m etatarsal bon es. Their wed ge shap e contributes to the formation and maintenance of the transverse arch of the foot.

The navicular lies between the head of the talus and the three cuneiform bones (Fig. 5-3). The tuberosity lies in front of and below the medial malleolus, and it attaches to the ma in part of t he tibialis posterior t end on.

Cuboid The cuboid articulates with the anterior end of the calcane um ( Fig. 5-3). It ha s a dee p groove on its inferior aspec t for the tendon of the peroneus longus muscle.

CHAPTER 5

Lower Limb

16 1

extensor digitorum longus tendons

extensor hallucis longus insertions of dorsal interossei extensor digitorum brevis (extensor hallucis brevis) third dorsal inteross eous second dorsal interosseous first dorsal interosseous

fourth dorsal inteross eous

first metatarsal bone

peroneus tertius

medial cuneiform intermediate cuneiform

peroneus brevis

lateral cuneiform navicular

cuboid

extensor digitorum brevis

talus calcaneum

tendo calcaneus Figure 5-3 Dorsal view o f the b one s of the ri ght foot. N ote the m uscle attachm

METATARSAL BONES AND PHALANGES The metatarsal bones and the phalanges resemble the metacarpal bones and the phalanges of the hand; each possesses a distal head , sha f t ,and proximal base (Fig. 5-3). There are five metatarsal bones, and they are numbered from the med ial to the lateral side. T he fifth metatarsalha s a prominent tubercle on its base, which can be easily palpa ted alo ng th e la tera l bo rde r of the foot. The tub erc le p rovides attachment to the peroneus brevis tendon.

ents.

Except for t he b ig toe, eac h toe h as three ph alanges. T he big to e p osse sses o nly two.

JOINTS Hip Joint ARTICULATION

Articulation is between the head of the femur and the acetabu lum of the hip b one (Fig. 5-4). The articular surf ace of


acetabulum acetabular labrum

acetabular foss a

capsule head of femur synovial membrane

pad of fat

ligament of head of femur

A articular surface synovial sheath epiphyseal line

synovial membrane acetabular labrum ligament of head of femur

transverse acetabular ligament

arterial supply from obturator artery

obturator artery

B

arterial supply from circumflex femoral arteries

synovial sheath

ligament of head of femur

small branch of obturator artery

Figure 5-4 A. Corona l se cti on o f the righ t hip j oint. B. Arti cular su rfaces o f the righ t hip j oint and the arterial supply of

the fem ur.

CHAPTER 5

the acetabulum is horseshoe shaped and is deficient inferiorly at the acetabular notch. The cavity of the ace tabulum is deepened by the fibrocartilaginous rim called the ac etabular labrum. The labrum b ridges the ace tabular notch and is called the tr ansverse acetabular ligament.

Lower Limb

16 3

intertrochanteric line of the femur in front of and halfway along the posterior aspect of t he n eck of the bon e be hind. It is reinforced b y the iliofemo ral, the pub ofemoral, and the ischiofemoral ligaments.

LIGAMENTS

TYPE The hip is a syno vial ball-an d-socke t joint.

CAPSULE The capsule encloses the joint and is attached medially to the a ce tab ular labru m ( Fig. 5-4). It is attach ed late rally to the

anterior inferior iliac s pine iliofemoral ligament

Iliofemoral Ligament The iliofemo ral ligamen t is the strongest and most impo rtant ligament of the hip joint (Fig. 5-5). It is shaped like an inverted Y. Its base is attached to the anteroinferior iliac spine abo ve, and the two li mbs of the Y are attach ed to the up per and the lower parts of t he intertrocha nteric li ne o f the femur

opening for bursa

superior ramus of pubis pubofemoral ligament

intertrochanteric line

A

capsule ischium

iliofemoral ligament

ischiofemoral ligament

intertrochanteric crest

area of loose attachment of capsule B Figure 5-5 Anterior ( A) and poste rior ( B) views of the right hip j

oint.


b e low . This liga m en t re sists h ype re xte n sio n a n d la te ra l rotation of the hip joint.

Pubofemoral Ligament The pubofemoral ligament is triangular in shape (Fig. 5-5). The base is attached above to the superior ramus of the pubis, a nd the ap ex is a ttac he d be low to the lowe r en d o f the intertrochanteric line. This ligament limits abduction and lateral rotati on of the h ip joint.

Ischiofemoral Ligament The ischiofemoral lig ame nt is spi ral in shape and is attach ed to the body of the ischium and laterally to the greater trochanter of the femur (Fig. 5-5). This ligament limits medial rotation of the h ip joint.

Ligament of the Hea d of the Femur The ligament of the he ad of the femur is f lat and triangular in shap e ( Fig. 5-4). It is attache d b y its apex to the fovea c ap itis of the femu r and by its base to the transvers e ac etabu lar ligament and to the margins of the acetabular notch. This ligament lies wit hin the joint and is ensheathe d b y synovial mem brane . It has a slig ht limiting action on add uction of the hip joint.

SYNOVIAL MEMBRANE The synovial memb rane lines the cap sule (Fig . 5-4) an d c overs the p ortion of the femoral ne ck that lies wit hin the joint cap sule. It enshea thes the lig ame nt of the h ead of the femur and covers the floor of the acetabular fossa. It frequently communicates with the psoas bursa.

IMPORTANT RELATIONS • Anteriorly: Femoral vess els and nerve. • Posteriorly: Sciatic nerve.

CLINICAL NOTES HIP J OINT STABILITY AND TRENDELENBURG ’S SIGN The stability of the hip joint when a p erson stand s on one leg with the foot of the op posite leg rai sed a bove the ground de pends o n three factors : • The glut eus medius and m inimus must be functi oning normally. • The hea d of the f emur must be located normall y within the acetabulum. • The nec k of the femur must be intact and must have a n ormal an gle with the shaft of t he femu r. If one of these factors is defective, then the pelvis will sink downward on the o pposite, unsupported side. The patient is then said to exhibit a positive Trendelenburg’s sign.

Kne e Jo int ARTICULATION Above are the co ndyles of the femur; below are the c ond yles of the tibia and their menisci (Fig. 5-6). In front is the articulation b etween the lower end of the femur and the p atella.

TYPE NERVE SUPPLY The femoral, the obturator, and the sciatic nerves and the nerve to the qua dratus femoris s upp ly the joint.

Between the femur and the tibia is a synovial joint of the hinge variety. Between the patella and the femur is a synovial gliding joint.

CAPSULE MOVEMENTS AND THE MUSCLES THAT PRODUCE MOVEMENT The h ip joint has a wide ran ge of movement. • Flexion: Iliopsoa s, rectus femoris , sartori us, and add uctor muscles. • Extension (posterior movement of the flexed thigh): Gluteus maximus an d h amstring muscles. • Abduction: Gluteus medius and minimus, sartorius, tensor fas ciae latae, an d piriformis muscles. • Adduction: Adductor longus and brevis, adductor fibers of adduc tor magnus, pectineus, and gracilis muscles. • Lateral rotation:Piriformis, obturator internu s an d externus, supe rior an d inferior gemelli , qua dratus femoris, and gluteus ma ximus muscles. • Medial rotation: Anterior fibers of the gluteus medius and minimus and the tensor fasciae latae muscles. • Circumduction: A combination of all the previously descri bed movements.

The capsule encloses the knee joint, except anteriorly, where the capsule is deficient. Here, the synovial membra ne po uc he s upwa rd b en ea th the qu ad rice ps ten do n an d forms the sup rapatellar bursa.

LIGAMENTS Extracapsular

Ligamentum Patellae The ligamentum patellae is a continu ation of the ten don of the quadriceps femoris muscle. It is attached above to the lower bo rde r of the p ate lla and b elow to the tu be rcle of the tibia.

Lateral Collateral Ligament The lateral collateral ligament is cordlike; it is attached above to the lateral condyle of the femur and below to the he ad o f the fibula ( Fig. 5-6). It is sepa rated from the lateral menisc us by the tendo n of the popliteus muscle.

CHAPTER 5

Lower Limb

16 5

shaft of femur suprapatellar bursa medial femoral condyle lateral femoral condyle

posterior cruciate ligament

infrapatellar fold of synovial membrane

anterior cruciate ligament

lateral meniscus

medial meniscus

capsule (cut open) patellar

shaft of fibula shaft of tibia

A

femur anterior cruciate ligament medial femoral condyle medial collateral ligament medial meniscus medial tibial condyle

lateral femoral condyle lateral meniscus lateral collateral ligament lateral tibial condyle shaft of fibula

shaft of tibia B Figure 5-6 A. Anteri or view of the internal asp

ect of the right knee joint. Note that the capsu le has b e e n cu t a n d th e p a te lla tu rn e d d o w n w a rd . B. Posterior vi ew of the internal aspe ct of the ri ght knee joint . Not e that the capsule and the synovi al mem brane ha ve been removed.

Medial Collateral Ligament The m edial co llateral li gamen t is a flat ba nd that is att ach ed above to the medial condyle of the femur and below to the med ial surface of the shaft of the tibia ( Fig. 5-6). It is str ongly attached to the med ial meniscus.

Oblique Popliteal Ligament The o blique po pliteal ligame nt is a tend inous expan sion of the semimembranosus muscle. It strengthens the back of the capsul e.

Intracapsular

Cruciate Ligaments The cruciate ligaments are two very strong ligaments that cross each other within the knee joint (Fig. 5-6). They are

termed anterior and posterior, according to their tibial attachments. The anterior cruciate ligament is attached below to the a nterior intercond ylar area of the tibia ( Fig. 5-7), an d it pa sses upwa rd, ba ckwa rd, an d latera llyto b e atta ch ed to th e lateral f emo ral cond yle. The posterior cruciate ligament is attached below to the posterior intercondylar area of the tibia (Fig. 5-7), and it pa sses u pwa rd, forwa rd, an d med ially to b e atta ch ed to the medial femoral condyle.

MENISCI The me nisci are C-shap ed shee ts of fibroc artilage (Fig. 5 -7). The peripheral convex border of each meniscus is thick and a ttached to the capsule, and the inner conc ave border is thin and forms a free edge. The upper surfaces are in


prepatellar bursa ligamentum patellae anterior cruciate ligament

capsule lateral meniscus

medial meniscus

medial collateral ligament

lateral collateral ligament tendon of popliteus

deep fascia semimembranosus medial head of gastrocnemius

popliteal artery

posterior cruciate ligament Figure 5-7 Cross-section of the ri

ght knee joi nt as se en from a bove. Note the po

siti ons o f the li gam ents a nd the me nisci .

contact with the femoral condyles and the lower surfaces

BURSAE REL ATED T O THEKNEE JOINT

with the tibial condyles. Each meniscus is attached to the upper surface of the tibia by the anterior and the posterior horns. Because the medial meniscus is also attached to the m edial c ollateral l igame nt, it is r elatively immo bile an d is very susceptible to injury. The function of these menisci is to deepen the articular surfaces of the tibial condyles to receive the convex femoral condyles.

Suprapatellar Bursa The suprap atellar bursa li es ben eath the qu adricep s muscle. It is the largest bursa , and it always communicates with the knee joint.

Prepatellar Bursa The p repatellar bursa li es between the pa tella an d the skin.

CLINICAL NOTES INJURIES

TO THELIGAMENTS ANDMENISCI

The ligaments and menisci are commonly injured in active s ports. The m edial men iscus is damaged m uch more frequen tly than the lateral, probab ly bec ause of its strong attachment to the medial collateral ligament, which restricts its mobility.

Infrapatellar Bursae The superficial infrapatellar bursalies be tween the ligamentum patellae and the skin. The deep infrapatellar bursa lies between the ligamentum patellae and the tibia.

Popliteal Bursa The p opliteal bursa surrounds the tendo n of the po pliteus. It always communicates with the joint c avity.

Semimembranosus Bursa SYNOVIAL MEMBRANE The synovial membrane lines the capsule. Anteriorly, it forms a pouch that extends up beneath the quadriceps femoris muscle to form the suprapatellar bursa. Posteriorly, it is prolonged do wnward on the tendo n of the popliteus muscle to form the popliteal bursa. The synovial membra ne is a lso re flecte d forward an d aro un d the front of th e cruciate ligamen ts; as a result, the c ruciate ligaments lie behind the synovial cavit y. In the anterior part of the lower region of the joint, the synovial membrane is reflected backward from the ligamentum patellae to form the infrapatellar fold.The ed ges of this fold are called the alar folds.

The semime mbran osus bursa li es between the ten don o f the semimembranosus muscle and the medial condyle of the tibia. It may communicate with the joint ca vity.

NERVE SUPPLY Femoral, obturator, common peroneal, and tibial nerves supply the joint.

MOVEMENTS AND THE MUSCLES THAT PRODUCE MOVEMENT • Flexion: Biceps femoris, semitendinosus, and semimemb ranosus muscles .

CHAPTER 5

• Extension: Quadricep s femo ris muscle. • Medial rotation: Sartorius, gracilis, and semitendinosus muscles. • Lateral rotation:Biceps femo ris mu scle.

Lower Limb

16 7

The inferior transverse tibiofibular ligament deepens the soc ket into which the b ody of the talus fits snugly.

TYPE

The knee joint is most stable when in full extension. As the kne e joint assumes this posit ion, med ial rotati on of the fem ur results in a twisti ng an d tighten ing of all the m ajor ligaments of the joint. During flexion, the ligaments are untwisted by contraction of the poplit eus muscle, which laterall y rotates the femur on the tibia.

The ankle is a synovial hinge joint.

CAPSULE The c apsule en closes the joi nt.

LIGAMENTS

CLINICAL NOTES

Medial (Deltoid) Ligament

STRENGTH

OF THEKNEE J OINT

The medial ligament is very strong and is attached by its ap ex to the tip of the me dial m alleolus ( Fig. 5-8). Below, the dee p fibers are attache d to the me dial surface of the b ody of the talus. The superficial fibers are attached to the medial side of the talus, the sustentaculum tali, the plantar calcaneonavicular ligament, and the tuberosity of the navicular bo ne .

The strength of t he kne e joint depen ds on the strength of the ligaments that bind the femur to the tibia and o n the tone of the muscles acting on the joint. The most important muscle group is the quadriceps femoris; pro vide d tha t this is we ll d eve lop ed , it is ca pa ble of stabilizing the knee in the p resence of torn li gamen ts.

Late ral Ligament

Ankle Joint

The lateral ligament is weaker than the medial ligament (Fig. 5-8) an d h as three b and s.

ARTICULATION

Anterior Talofibular Ligament

The articulation is between the lower end of the tibia, the malleoli above, and the body of the talus below (Fig. 5-8).

The anterior talof ibular lig ame nt runs from the lateral malleolus to the lateral surf ace of the talus.

tibia

fibula

talus

lateral malleolus

anterior talofibular ligament posterior talofibular ligament

calcaneofibular ligament

bifurcated ligament

A

tibia

medial malleolus

navicular medial (deltoid) ligament

calcaneum sus tentaculum tali

B Figure 5-8 Right ankle joint.

A. Late ral view. B. Med ial view.


Calcaneofibular Ligament

Ligaments

The calcaneofibular ligament runs from the lateral malleolus to the lateral surf ace of the c alcane um.

Plantar Calcaneonavicular (Spring) Ligament

The posterior talofibular ligament runs from the lateral malleolus to the p osterior tube rcle of the talus.

The p lantar calcan eon avicular l igame nt runs f rom the a nterior b order o f the sustentaculum tali to the inferior surf ace and the tuberosity of the navicular bone. It supports the hea d of the talus.

SYNOVIAL MEMBRANE

CALCANEO CUBOID O J INT

The synovi al mem brane lines the c apsule.

Articulation

Posterior Talofibular Ligament

NERVE SUPPLY Deep peron eal an d tibial nerves s upp ly the joint.

Articulation is between the anterior end of the calcaneum and posterior s urface of the cu boid.

Type The calcan eoc ubo id joint is a synovi al gliding joint.

MOVEMENTS AND THE MUSCLES THAT PRODUCE MOVEMENT • Dorsiflexion (toes pointing upward ): Tibialis anterior, extensor ha llucis longus, extensor digi torum longus, an d p erone us tertius muscles. • Plantar flexion (toes pointing downward): Gastrocnemius, soleus, plantari s, peroneu s longus, peroneu s brevis , tibialis posterior, flexor digitorum longus, and flexor hallucis longus muscles.

IMPORTANT RELATIONS • Anteriorly: Anterior ti bial vess els and the dee p pe ronea l nerve (Fig. 5-9). • Posteriorly: Tendo calcaneus (Fig. 5-10). • Behind the lateral malleolus: Tendons of peroneus longus a nd bre vis (Fig. 5-10). • Behind the medial malleolus:Posterior tibial vessels, tibial nerve, an d the long flexor ten do ns of the foot ( Fig. 5-10).

Inte rtarsal Jo ints SUBTALAR JOINT Articulation The articulation is between the concave inferior surface of the bod y of the talus and the c onvex face t on the uppe r surface of the c alcaneum.

Ligaments

Long Plantar Ligament The long plantar lig ame nt is strong and con nec ts the u nde rsurface of the c alcaneum to the cub oid and the bases of t he third, the fourth, an d the fifth me tatarsal bones.

Short Plantar Ligament The short plantar lig ame nt is wide an d strong and co nne cts the undersurface of the calcaneum to the adjoining part of the cuboid.

MOVEMENTS AND THE MUSCLES THAT PRODUCE MOVEMENT The movements of the subtalar, the talocalcaneonavicular, and the calcaneocuboid joints are inversion and eversion. Inversion is more extensiv e than eversion. • Inversion (movement of the foot so that the sole faces medially): Tibialis anterior, extensor hallucis longus, medial tendo ns of extensor digi torum longus, and tibialis posterior m uscles. • Eversion (op posite moveme nt of the f oot so that the sole faces laterally): Peroneus longus, peroneus brevis, peroneus tertius, and lateral tendons of extensor digitorum longus muscles.

CUNEO NAVICUL AR JOINT Type The subta lar joint is a sy no vial gliding joint.

Articulation Articulation is between the three cuneiform bones and the navicular bo ne.

TALOCAL CANEONAVICUL AR JOINT Articulation Articulation is between the rou nde d he ad o f the talus, upper surface o f the sustentaculum tali of the calca neu m, and p osterior con cave surf ace of the n avicular bone.

Type The talocalcaneonavicular joint is a synovial joint.

Type This is a synovial gliding joint.

CUBOIDEONAVICUL AR J OINT The cub oideon avicular joint is a f ibrous joint. The bon es are connected by dorsal, plantar, and interosseous ligaments, and a small amoun t of moveme nt is possible.

CHAPTER 5

Figure 5-9 Structures of the anterior and lateral ri

ght leg and o f the do rsum of the f oot.

Lower Limb

16 9


flexor hallucis longus

peroneus brevis peroneus longus lateral malleolus superior peroneal retinaculum synovial sheath

peroneal artery

inferior extensor retinaculum tendo calcaneus fifth metarsal bone

inferior peroneal retinaculum

A abductor digiti minimi

tibia tibialis posterior flexor digitorum longus posterior tibial artery tibial nerve flexor hallucis longus medial malleolus

flexor retinaculum tibialis anterior tendo calcaneus

flexor hallucis longus medial plantar artery

medial calcaneal nerve and artery

medial plantar nerve lateral plantar artery lateral plantar nerve B

abductor hallucis flexor digitorum brevis

Figure 5-10 Structures pa

ssing be hind the lateral the p ositi on o f the retinacula.

ma lleolus ( A) and the m edial mall eolus ( B). Note

CHAPTER 5

Lower Limb

17 1

INTERCU NEIFORM AND CUNEO CUBOID OINTS J

Sacrotuberous Ligament

Intercun eiform a nd cun eoc ubo id joints are synovi al gliding join ts. The b on e s are c on n ec te d b y d orsa l, p lan ta r, an d inteross eou s ligaments.

The sacrotube rous ligamen t conn ects the p osteroinf erior iliac spine, the lateral part of the sacrum, and the coccyx to the ischial tu be rosity (Fig. 5-11).

TARSOMETAT ARSAL AND INTERMETATA RSAL JOINTS Tarsometatarsal and intermetatarsal joints are synovial gliding joints. The b one s are con nec ted b y dorsal, plantar, and inteross eou s ligaments.

Sacrospinous Ligament The sacrospinous ligament connects the lateral part of the sacrum and the coccyx to the spine of the ischium (Fig. 511).

IMPORTANT FORAMINA METATARSOPHALANGEAL AND INTERPHALANGEAL Grea ter Scia tic Foramen J OINTS Metatarsopha langeal an d interph alangeal joints are simil ar to those of the han d ( see p. 12 3 and 124 ). Abd uction an d ad duction of the toes, which are performed by the interossei muscles, are small in amount and occur from the midline of the second digit (a nd no t the third dig it, as in the ha nd) .

MUSCLES OF THE LOWER LIMB Gluteal Region The gluteal region is bounded superiorly by the iliac crest and inferiorly by the fold of the buttock (Fig. 5-11). This region consists largely of the gluteal muscles and a thick layer of supe rficial fascia. The m uscles of t he gluteal region are d escribed in Table 5-1.

CLINICAL NOTES GLUTEUSMAXIMUS AND INTRAMUSCULARINJECTIONS The great thickness of the gluteus maximus muscle makes it ideal for intramuscular injections. To avoid injury to the underlying sciatic nerve, the injection

The greater sciati c foramen is formed by the c onversi on of the greater sciatic notch of the hip bone into a foramen by the pre sen ce of the sac rotu be rou s an d th e sa cro spin ou s ligaments. The following structures pass through the forame n: • • • • •

Piriformis muscle. Sciatic nerv e. Posterior cutaneou s nerv e o f the thigh. Supe rior and inferior gluteal nerves. Nerv es to obturator i nternus and q uadratus f emoris muscles. • Pudendal nerv e. • Supe rior and inferior gluteal arteri es and veins. • Internal puden dal art ery and vein.

Lesser Sciatic Foramen The lesser sciatic foramen is formed by the conversion of the lesser sciati c notch of the hip bo ne into a for amen by the presence of t he sacrotuberous and the sacros pinous ligaments. The following structures pass through the forame n: • • • •

Tendo n of the ob turator i nternus muscl e. Nerve to the o bturat or inter nus muscle. Pudendal nerv e. Internal puden dal art ery and vein.

should be given well forward on the upper outer quadrant of the b utt ock.

Thigh

The superficial fascia is thick (espe cially in women ) and is impregnated with large q uan tities of fat.

The muscles of the anterior fascial compartment (Fig. 5-12) are d escribed in Table 5-2. The muscles of the med ial fascial com partmen t are described in Table 5- 3, and the muscles of the p osterior fascial compa rtment ( Fig. 5-13) are d escribed in Tab le 5-4.

Dee p Fascia

DEEP FASCIA OF THE THIGH (FASCIA LATA)

The d eep fascia is continuo us be low with the fascia lata of the thigh, and it spli ts to en close the gluteus ma ximus muscle.

The deep fascia encloses the thigh as a trouser leg would. The upper end is attached to the pelvis and its associated ligaments.

FASCIA Superficial Fascia

IMPORTANT LIGAMENTS ILIOTIBIAL TRACT The sac rotuberou s and the sacrospino us ligamen ts stabilize the sacrum and prevent its rotation by the weight of the vertebral column.

The iliotibial tract is a thickening of the fascia lata on its lateral side. It is attache d ab ove to the il iac tubercle a nd b elow


iliac crest gluteus medius posterior superior iliac spine superior gluteal artery

sacrotuberous ligament gluteus minimus

superior gluteal artery inferior gluteal artery and nerve spine of ischium

tensor fasciae latae superior gluteal nerve

nerve to obturator internus pudendal nerve sacrospinous ligament internal pudendal artery coccyx

piriformis gemellus superior oburator internus gemellus inferior greater trochanter

ischiorectal fossa anus

posterior cutaneous nerve of thigh

fat

quadratus femoris

semimembranosus

adductor magnus gracilis iliotibial tract

nerve to hamstrings adductor magnus

sciatic nerve gluteus maximus

biceps femoris semitendinosus Figure 5-11 Structures of the ri imus and part of t he gluteus med

ght gluteal region. N ote that the g reater pa rt of the gluteus m ius m uscl es have be en remo ved.

ax-

CHAPTER 5

Table 5-1

Ori g i n

In s e rt i o n

Ne rvSeu p p l y

Outer surface o f the ilium,sacrum, coccyx,and sa crotuberous liga ment Outer surfa ce ofthe ilium

Iliotibial tra ct and glutealtuberosityof thefemur

Inferior gluteal nerve

Greater trocha nter of thefemur

Superior glutea l nerve

Gluteus minimus

Outer surfaceo fthe ilium

Greater trocha nter of thefemur

Superior gluteal nerve

Tensorfascia e la ta e

Iliac crest

Iliotibialtra ct

Superiorglutea l nerve

Piriformis

Gemellusinferior

Ischialtuberosity

Greater trocha nter of thefemur Grea ter troc ha nter of thefemur Greater trochanter of the femur Greater trochanter of the femur

First ands econd sacranerves l Sac ral plexus

Gemellus superior

Anterior surfa ceo fthe sacrum Inne r surfac e of the obturatormembrane Spin e of the ischium

Quadra tus femoris

Ischial tuberosity

Gluteus medius

Obturator internu s

17 3

Muscle s of the Gluteal Region of the Lower Limb

Mu s c l e

Gluteus maximus

Lower Limb

Quadra teend tubercle on the upper ofthefemur

to the lateral cond yle of the tibia. It r ece ives the insertion of the greater part of the gluteus maximus and the tensor fasciae latae m uscles.

Sacral plexus Sacralplexus

Ac ti o n

Extends and latera lly rotatesthethigha t the hipjoin t; itextendsknee joint throughthe iliotibial tract Abducts the thigh at the hip joint;tiltsthepelviswhen walking Abducts thet high at theh ip joint;tiltsthepelviswhen walking; anterior fibers med ially rotate the thigh Assiststhe gluteusma ximus inextending the knee joint Laterallyrota testhet high a t thehipjoint Later ally rotates the thigh at thehipjoint Laterally rota tes the thigh at the hip joint Laterally rota testhe thigh at the hip joint

Sacral plexus

Laterally thehipjointrota tes the thigh at

FEMORAL TRIANGLE The femo ral triangle is si tuated in the u ppe r part of the front of the thigh. Its boundaries are as follows:

SAPHENOUS OPENING

• Superiorly: The inguinal li gamen t. • Laterally:The sartorius m uscle. • Medially: The adductor longus muscle.

The opening a gap the in the deep fascia in the frontsaphenous of the thigh and justisbelow inguinal ligament. It allows passage of the great saphenous vein, some small b ra n c he s of th e fem or al ar te ry, a nd lymp h vess e ls. The opening is filled with loose connective tissue called the cribriform fascia.

The femoral triangle contains the terminal part of the femoral nerve and its branches, the femoral sheath, the femoral artery and its branches, the femoral vein and its tributaries, and the inguinal l ymph no des.

FEMORAL SHEATH FASCIAL COMPARTMENTS OF THE THIGH

• Anterior w ith the femoral nerve.

The femoral sheath is a downward protrusion from the abdom en into the thigh of the fascia transv ersalis and the fascia iliaca. The sheath surrounds the femoral blood vessels and lymph vessels for approximately 1 in. (2.5 cm) below the inguinal ligament. As the femoral artery enters the thigh be nea th the inguinal l igame nt, it occ upies the lateral compartment of the sheath. The femoral vein occupies the intermediate compartment, and the lymph vessels

•• Medial (adduc tor)swi th the obturator nerv e. Posterior with the ciatic nerv e.

(and usual ly one lymph node) compartment.

Three fascial septa pass from the inner aspect of the deep fascial sheath of the thigh to the linea aspera of the femur. By this mea ns, the thigh is divided into three co mpa rtments, with each having muscles, nerves, and arteries. The compa rtme nts a re a s follows:

occupy the most

medial


anterior superior iliac spine lateral cutaneous nerve of thigh sartorius femoral nerve

iliacus psoas femoral artery femoral vein femoral sheath femoral canal inguinal ligament

lateral efemoral circumfl x artery profunda femoris artery tensor fasciae latae

pubic tubercle deep external pudendal artery spermatic cord pectineus medial cutaneous nerve of thigh

medial femoral circumflex artery intermediate cutaneous nerve of thigh

adductor longus adductor magnus gracilis

nerve to vastus medialis vastus intermedius vastus lateralis vastus medialis shaft of femur

femoral artery

saphenous nerve

iliotibial tract

rectus femoris

ligamentum patellae saphenous nerve

Figure 5-12 Femora l triang le and the a dductor (subs

artori al) cana l in the right lower limb.

CHAPTER 5

Table 5-2 Mu s c l e

Ori g i n

Anterior superior iliacspin e

Ilia cus

Iliac fossa of the hipbone

Psoas

Twelfth thoracic vertebralbody; transverseprocesses, bo die s, an d interv ertebral discs of the fiv e lumb ar vertebae Superior ramusof the pubis

Quadratus femoris Rectus femoris

Vastus lateralis Vastus medialis Vastusintermedius


Gracilis

Adductor longus

17 5

Muscle s of the Anterior Fasc ial Compartment of the Thigh

Sartorius

Pectineus

Lower Limb

Straight head;a nterior inferioriliacspine; reflected hea d: ilium above the acetabulum Upper en d and shaft ofthefemur Upper en d and shaft of the femur Sha ft offemur

In s e rt i o n

Upper medialsurface ofthesha ftofthetibia

With psoas into the lesser trochanterofthefemur

Ne rvS eu p p l y

Femoraln erve

Femoral nerve

With the iliacusinto the lessertrochanterofthe femur

Lumbarplexus

Upper end ofthe sha ft of the femur

Femoraln erve

Ac ti o n

Flexes,abducts,and laterally rotatesthethigha tthehip joint; flexes a nd me dia lly rotates the leg at the knee joint Flexes the thigh on the trunk; if thethighisfixed,itflexesthe trunk on the thigh ( as in sitting up from lying down) Flexesthe thigh on the trunk;if the thigh isfixed,itflexesthe trunkonthethigh( asin sitting up from lying d own )

Flexesand a dductsthe thigh a t the hip joint

Quadriceps tendon intothepa tella

Femoralnerve

Extends the leg at the kn ee joint;flexesthethighatthe hip joint

Quadr icep s ten don intothepa tella Quadr icep s ten don into the pa tella Quadricepstendon into the patella

Femoral ne rve

Exten ds the leg at the knee joint

Femoral ne rve Femoralnerve

Exten ds the leg at the kne e joint Extendsthe legat the kn ee joint

Musc les of the Medial Fas cial Compartment of the Thigh Ori g i n

Inferior ra musofthe pu bis a nd ram us o f the ischium Body ofthe pubis

In s e rt i o n

Upper partofthe shaft of the tibia Posterior surfa ce ofthe shaftofthefemur

Adductor brevis

Inferior ramus of the pu bis

Posterior surfa ce of the sha ft of the fem ur

Add uctor magnu s

Inferior ram us of the pu bis, ra mu s of the ischium,and ischial tuberosity

Poster ior sur fac e of the sha ft of the fem ur, adductortubercle ofthefemur

Obturator externus

Outer surfa ceo fthe obturator membrane

Greater trocha nter of the femur

Ne rvSeu p p l y

Obturator nerve

Ac t i o n

Adductsthe thigh atthe hip joint; flexes th e le g at th e knee joint Obturator nerve Adducts the thigh at the hip joint,assistsinla teral rotation Obturator nerve Adducts the thigh at the hip joint, a ssists in late ral rotation Obturator ne rve Add uc ts the thigh at the hip ad du cto r pa rt; joint, a ssists in late ral scia tic nerve: rotation, ha mstringpart hamstringpart extend s the thig h at the hip joint Obturator nerve Laterally rota tes thet high at the hip joint


iliac crest

gluteus medius gluteus minimus

gluteus maximus

piriformis ischial spine

gemellus superior obturator internus gemellus inferior greater trochanter

sacrotuberous ligament

qaudratus femoris adductor magnus

ischial tuberosity

nerve to hamstrings sciatic nerve adductor magnus (hamstring part)

gluteus maximus

semimembranosus semitendinosus

gracilis biceps femoris (long head)

common peroneal nerve

oblique popliteal ligament tibial nerve popliteus

semimembranosus Figure 5-13 Structures of the p

osterior aspe

ct of t he right thigh.

CHAPTER 5

Table 5-4

Lower Limb

17 7

Musc les of the Posterior Fas cial Compartment of the Thigh

Mu s c l e

O ri g i n

In s e rt i o n

Ne rvSeu p p l y

Bicepsfemoris

Long head:ischial tuberosity;short head:sha ftofthe femur

Heado fthef ibula

Scia ticn erve( lon g head:tibialnerve; shorthead:common peroneanerve) l

Semitend inosus

Ischial tube rosity

Upper part of the m edial surface ofthe sha ftof thetibial

Sciatic n er ve ( tibial portion)

Semimembr an osus

Ischial tube rosity

Medial co ndyle o f the tibia ,formsthe oblique po plitea l ligame nt

Sciatic n er ve ( tibial portion)

Add uc tor ma gnu s ( hamstring portion)

Isch ial tub erosity

Add uc tor tub ercle o f the femur

Sciatic ne rve (t ibial portion)

Ac ti o n

Flexesa ndl a terally rotates thelegatthekneejoint; thelongheada lso extendsthethighatthe hip joint Flexes an d m edially rotates the legatthe knee joint andextends thethighat the hip joint Flexes an d m edially rotates the legatthe knee joint an d e xten ds th e th igh a t the hip joint Exten ds the thigh at the hip joint

FEMORAL CANAL

ADDUCTOR (SUBSARTORIAL) CANAL

The femoral canal is the small, medial compartment of the femoral sheath occupied by the lymphatics. It is approxima tely 0.5 in. ( 1.3 cm ) in len gth. It is also a p oten tially wea k area in the wall of the ab dom en; a protrusi on of peritoneum could be forced down the femoral canal to form a femoral hernia.

The addu ctor cana l is an intermuscular cl eft on the m edial aspe ct of the midd le third of the thigh ben ea th the sartorius mu scle. The posterior wall is formed by the adductor magnus muscle, the lateral wall by t he vastus medialis, and the an teromed ial wall by the sartorius muscle a nd fascia. The c ana l contains the femoral artery and vein, the de ep lymph vessels, the saphenou s nerve, and the nerve to the vast us med ialis muscl e.

FEMORAL RING The femoral ring is the up per op ening of the femoral can al. It is filled by a plu g of extra pe ritonea l fat ca lled the femoral septum.

Important Relations • Anteriorly: Inguinal ligamen t. • Posteriorly: Superior ramus of the pubis and the pe ctin ea l ligame nt. • Laterally:Femoral vein. • Medially: Lacu nar ligame nt (an extension of t he inguinal ligamen t; see p age 39).

Kne e Regio n POPLITEAL FOSSA The popliteal fossa is a diamond-shaped, intermuscular space at the back of the knee (Fig. 5-14). It contains the po plite al vesse ls, the sma ll sap he no us vein , the co mm on pe ron ea l and tibia l nerve s, the p oste rior cu tan eo us ne rve of the thigh, con nec tive tissue, and lymph n ode s.

BOUNDARIES • Laterally:The b iceps femo ris muscle abo ve and the lateral head of the gastrocnemius and plantaris muscles below. • Medially: The semimembranosus and semitendinosus muscles above and the med ial head of the gast rocnemius muscle below.

CLINICAL NOTES

Le g FEMORALHERNIA • A protr usion o f the a bdom inal pari etal peri toneum down through the femoral canal to form the hernial sac. • More common in w omen than in men. • The n eck of the hernial s ac lies below and later al to the pubic tube rcle. • The ne ck of the hernial sac li es at the femoral ri ng and is related anteriorly to the inguinal ligament, po sterio rly to the pe ctin ea l ligame nt, la tera lly to th e femo ral vein, and med ially to the sha rp, free ed ge of the lacunar ligament.

The muscles of the anterior fascial compartment (Fig. 5-9) are described in Table 5-5. The muscles of the lateral fascial com partmen t (Fig. 5-9) a re de scribed in Table 5-6, and the muscles of the posterior fascial compartment (Fig. 5-15) are described in Table 5-7. The m uscle on the d orsum of the foot is desc ribed in Table 5-8.

FASCIAL COMPARTMENTS OF THE LEG The deep fascia surrounds the leg and is continuous above with the dee p fascia of t he thigh. I t is attache d to the anterior and the medial borders of the tibia, and two intermuscular septa pass from its deep aspect to be attached to the fibula. Together with the interosseous mem bran e, the septa divide


Figure 5-14 Boundaries an

d conten ts of the ri ght pop liteal f ossa .

CHAPTER 5

Table 5-5

Ori g i n

In s e rt i o n

a

Ne rvSeu p p l y

Ac ti o n

Tibialis an ter ior

Sha ft of the tibia an d the interosseous membran e

Med ial cu ne ifor m an d ba seofthefirst metatarsalbone

Dee p pe rone al ne rve

Exten sor digitorum longus

Sha ft of the fibu la a nd theinterosseous membra ne Shaft of the fibula a nd theinterosseous membra ne

Exten sor expan sion of thela teralfourtoes

Dee p pe ron ea l ner ve

Peron eus tertius

Exten sor ha llucis lon gus

Sha ft of the fibu la a nd theinterosseous membra ne

Extens ion (or dors iflexion) of the ankle is the move


17 9

Musc les of the Anterior Fas cial Compartment of the Leg

Mu s c l e

a

Lower Limb

Ba se ofthe fifth metatarsalbone

Deep peroneal nerve

Base o f the distal pha lanxofthe great toe

Dee p p er on ea l ner ve

ment o f the foot away from the grou

Exten ds the foo t at the anklejoint,invertsthe footatthesubtalarand the transverse tarsal joints, a nd ho lds u p th e med ial longitudinal arch o f the foot Exten ds the toe s an d dorsiflexesthefootat the ankle join t Dorsiflexes the foot at the anklejointa ndeverts foot the atsubtalar and the transverse tarsal joints Exten ds the big toe , dorsiflexesthefoota t the ankle joinat,nd invert s the foot at the subtal ar and the transverse tarsal joints

nd.

Muscle s of the Lateral Fascial Co mpartment of the Leg Ori g i n

In s e rt i o n

Ne rv S eu p p l y

Per on eu s lon gus

Sha ft of fibu la

Base o f first metatar sal bo ne an d th e m ed ial cun eiform

Sup erficial pe ron ea l ne rve

Per oneus br evis

Shaft of the fibu la

Base of the fifth metatarsalbone

Superficial peronea l n erve

Ac ti o n

Plan tar flexes the foo t at the an kle joint, e verts the foot a t the subtalarandthetransverse tarsal joints, holds up the lateral longitudina l arch o f the foot, and supports the transv erse arch Plantar flexes the foot at the ankle joint,evertsthefoota tthe subtalar and the transverse tarsal joints, and ho lds up the lateral longi tudinal arc h o f the foot


Figure 5-15 Structures of the p

osterior aspe ct of t he right leg. A. The gastrocnemius muscle is sho wn in ful l. B. Part of t he gas troc nem ius m uscl e has b een rem oved.

CHAPTER 5

Table 5-7

Ori g i n

Superficial G rou p Gastrocn emius

In s e rt i o n

Media la nd latera l condylesofthefemur

Planta ris

Lateralsupracondylar ridgeof thefemur

Soleus

Shaftsofthetibia a ndthefibula

Flexor digitorum longus

Via tendo calcaneus ( Achillestendon) intotheca lcaneum Calca neum

Viatendocalcaneus ( Achillestendon) intotheca lcaneum

Lateralcondyle of the femur

Shaftofthe tibia

Shaftofthe tibia

Basesofthe distal phalangesof thelateralfourtoes

Flexor hallucis longus

Shaftofthe fibula

Base ofthe distal phalanx of thebig toe

Tibia lisposterior

Shaftsofthe tibia a ndthefibulaan d the interosseous membrane

Tuberosityofthe na vicularandother neighboringbones


Exten sor digitorum bre vis

18 1

Muscle s of the Posterior Fasc ial Compartment of the Leg

Mu s c l e

Deep Grou p Popliteus

Lower Limb

Ne rvSeu p p l y

Tibia lnerve

Tibialnerve

Tibia lnerve

Tibia lnerve

Tibialnerve

Tibialnerve

Tibia lnerve

Ac ti o n

Pla ntar flexesthe footat the a nklejoint,flexestheknee joint Plantarflexesthefoota tthe a nklejoint,flexestheknee joint Togetherwiththe gastrocnemiusand theplantaris,itisapowerful flexor of the ankle joint; pro vide s the ma in pro pu lsive force in wa lking and running Flexesthe lega tthe knee joint; unlocks the knee joint by laterally rotating the femur on the tibia, thus sl acke ning the ligaments of the joint Flexesthe dista lphalanges ofthelateralfourtoes, planta rflexesthefoot,a nd supports the medial and the lateral longi tudinal arche s of the foot Flexesthe distalphalanxofthe big toe, plantarflexes the foot at the a nkle joi nt, and supports the medial longitudina l arch o f the foot Pla ntar flexesthe foota tth e a nklejoint,in vertsthefoot a tthe subtalarand the transverse tarsal joints, and supports the medial longitudinal a rch o f the foot

Muscle on the Dorsum of the Foot O ri g i n

Calca ne um

In s e rt i o n

By fou r ten do ns into t he pr oximal ph ala nx o f the b ig toe ( som etim es called the extensor ha llucis brevis) and long extensor tendons to the second, third, and fourth toes

Ne rvSeu p p l y

Dee p p eron ea l ne rve

Ac t i o n

Exten ds the first, sec on d, third , an d fou rth to es


the leg into three compartments, with each having its own muscles, blood supply, and nerve supply. The compartments are as follows:

sels, and m uscles. Its apex is att ach ed to the me dial and the lateral tubercles of the calcaneum. The base of the aponeurosis divides into five slips that pass into the toes.

• Anteri or with the deep peroneal nerve. • Lateral (peroneal) with the superfi cial peroneal nerve. • Posterior with the ti bial nerve.

ARCH ES OF THE FOOT

INTER OSSEOUS MEMBRA NE

Medial Longitudinal Arch

The interosseous membrane binds the tibia and the fibula together and p rovides attach men t for the muscles.

The medial longitudinal arch is formed by the calcaneum, the talus, the navicular bone, three cuneiform bones, and the first (medial) three metatars al bones.

Ankle

• Muscular support: Medial part of the flexor digitorum bre vis, a bd uc tor ha lluc is, flexor ha lluc is lon gus, me dia l pa rt o f the flexor digitoru m lon gus, flexo r h allu cis b revis, tibialis anterior, and ten dinous e xtensions of the inserti on of the tibialis posterior. • Ligamentous support: Plantar and dorsal ligaments, including the important calcaneonavicular (spring) ligamen t, the m edial lig ame nt of the a nkle joint, and the p lantar aponeurosis.

RETINACULA The retinacula are thickenings of the deep fascia that keep the long tendons around the ankle joint in position and act as pulleys (Fig. 5-10).

Superior Extensor Retinaculum The superior extensor retinaculum is attached to the distal end s of the a nterior borders of the f ibula an d the tibia (Fi g. 5-9).

Inferior Extensor Retinaculum The inferior extensor retinaculum is a Y-shaped band located in front of the ankle joint (Fig. 5-9).

Flexor Retinaculum The flexor retinaculum extends from the medial malleolus to the med ial surface of the ca lcane um (Fig. 5-10). It binds the deep muscles of the back of the leg to the back of the med ial malleolus as t hey pass f orward to en ter the sole.

Superior Peroneal Retinaculum The superior peroneal retinaculum connects the lateral malleolus to the lateral surf ace of the c alcane um (Fig. 5-10). It binds the tendo ns of the p erone us longus and brevis muscles to the ba ck of the lateral mall eolus.

Inferior Peroneal Retinaculum The inferi or peron eal retinaculum binds the ten don s of the pe ron eu s longu s and b revis musc les to the la tera l side o f the calcaneum (Fig. 5-10).

There a re three bon y arches in the sole.

Lateral Longitudinal Arch The lateral longitudinal arch is formed by the calcaneum, the cub oid, and the fourth an d the fifth metatarsal bone s. • Muscular support:Abductor digiti minimi, lateral part of the flexor digitorum longus and brevis, and peroneus longus and brevis. • Ligame ntous suppo rt: Long a nd short plantar lig ame nts and plantar aponeurosis .

Transverse Arch The transverse arch is formed by the b ases of the me tatarsal b on e s, th e cu b oid , an d th e th re e c un eifo rm b on e s. The wedge shape of the cuneiform bones and the bases of the metatarsal bone s play a large rol e in the support of the transverse arch . • Muscular interosslongus ei, transv he ad of the adductorsupport: hallucis, Dorsal and peroneus and erse brevis. • Ligamen tous support:Deep transverse ligaments and very strong plantar ligaments.

ARTERIES OF THE LOWER LIMB Femoral Artery

Sole of F oo t The mu scles of the so le ( Figs. 5-16 and 5-17) are usua lly de scribed in four layers (from inferior to superior). These mu scles are listed in Table 5-9.

DEEP FASCIA Plantar Aponeurosis The plantar aponeurosis is a triangular thickening of the deep fascia that protects the underlying nerves, blood ves-

The femo ral artery is a con tinuation o f the e xternal iliac a rtery (Fig. 5-18). It begins behind the inguinal ligament, where it lies midway between the an terior superior il iac spine an d the symphysis pubis (the site for taking a femoral pulse). The artery descends through the femoral triangle (Fig. 5-12) and the ad duc tor canal, and it leaves the fr ont of the thig h b y passing through the opening i n the add uctor magnus and then e ntering the po pliteal spac e a s the po pliteal artery (Fig . 5-14). In the femora l triangle, the a rtery is relate d latera lly to the femo ral nerve and med ially, in the upp er part of it s course, to the femo ral vein and the femoral cana l.

CHAPTER 5

first lumbrical second lumbrical third lumbrical fourth lumbrical

digital nerves

digital nerve plantar arch

flexor hallucis longus

deep branch of lateral plantar nerve

lateral plantar nerve

lateral plantar artery

medial plantar nerve flexor digitorum longus medial plantar artery

flexor digitorum accessorius (quadratus plantae)

Figure 5-16 Secon d layer of the plantar m p la n ta r a rt e rie s a n d n e rv e s .

uscles of the ri

ght foot. Note the m edial and the lateral

Lower Limb

18 3


fibrous flexor sheath of second toe

digital synovial sheaths

flexor hallucis longus flexor digitorum longus

synovial sheath of flexor digitorum longus synovial sheath of peroneus brevis

tibialis posterior

synovial sheath of peroneus longus synovial sheath of flexor hallucis longus

Figure 5-17 Synovial she aths of tendo ns on the so le of the ri ght foot.

18 4


First Laye r Abd uctor hallucis

Muscles of the Sole O ri g i n

In s e rt i o n

Ne rvSeu p p l y

Med ial side o f the b ase oftheproximalphala nx of the big toe Medi al ph alanx of the four la tera l toe s

Medial plantar nerve

Flexor digitorum bre vis

Medial tube rcle o f the ca lcaneum,flexor retin aculum Med ial tube rcle o f the ca lca ne um

Abd uc tor digiti minimi

Med ial an d later al tuberclesofthe

Lateral side of the ba se oftheproximalphala nx

Later al plan tar ne rve

Second Layer Flexor digitorum a ccessorius

Flexor digitorum longus

ca lcaneum Med ial an d later al sidesofthe calcaneum Sha ft of the tibia

Medi al plant ar ne rve

of the fifth toe Ten do n o f the flexor digitorumlongus Base of the dista l phalanx ofthela teralfourtoes

Flexes and a bdu cts the b ig toe, supportsthemediallongitudinal a rch Flexes the lateral fou r toe s, sup po rts the me dia l an d th e lateral longi tudinal arche s Flexes an d a bd ucts the fifth t oe , supportsthelaterallongitudina l a rch


Assists the long flexor ten do ns toflexthelateralfourtoes

Tibial nerve

Flexes the dista l pha langes of thelaterafour l toes,plantar flexes the foot, and supp orts the longitudinal arches First lumb rical : med ial Extends the toes at the pla nta r nerve; in terphalangea ljoints remainder: deep bra nc h o f the la tera l pla nta r ne rve Tibial nerve Flexes the d ista l pha lanx of the b ig toe, plantar flexes the foot, a nd supports the med ial longitudinal arch

Lumb rical s (4)

Tendo ns of the flexor digitorum longus

Flexor hallucis longus

Sha ft of the fibula

Base o f the d ista l phalanx of the big toe

Cubo id an d l ater al cu ne iform b on es; tibia lisposterior insertion

Med ial an d l ater al side s of the ba se o f the proxima lphalanxof thebigtoe

Med ial plan tar ne rve

Bases of the sec on d, third, and fourth metatarsa l bones Planta r liga ments

Lateral side of the ba se of the proximal phalan x of the b ig toe La teral side o f the b a se oftheproximalpha la nx of the big toe Lateral side of the ba se ofthep roximal phala nx of the little toe

Dee p b ran ch of the Flexes the big toe, supp orts the later al plantar nerve transverse arch

Third Layer Flexor h alluc is bre vis

Addu ctor hallucis Obliqu e h ea d

Transverse head Flexor digiti minimi brevis

Base of the fifth metatarsal bone

Dorsal extens or expan sion ofth e la teralfour toes

Ac t i o n

Deep b ranch o f the la tera lplantarnerve La teral pla ntar nerve

Flexes the m etatarsop ha lan gea l joint o f the b ig toe , sup po rts themediallon gitudin ala rch

Flexes the b ig toe, supports the transversearch Flexes the little toe

Fourth Layer Interossei

Dorsal (4)

Adjac en t side s of the metatarsa lbones

Bases of the ph alan ges a nd the dorsalexpansion ofthecorrespondingtoes


Plan tar (3)

Infer ior surfac es of the third,fourth,and fifthmeta ta rsa l bo ne s Sha ft of the fibu la

Bases of the ph alan ges a ndthedorsalexpansion ofth ecorrespondingtoes


Base o f the first me tatar sal bo ne an d th e m ed ial cuneiform

Sup erficial pe ron eal ne rve

Tub er osity of the na vicu lar andotherneighborin g bones

Tibial ne rve

Per on eus lon gus

Tibialis po sterior

Sha fts of the tibia a nd thefibulaandthe interosseous membrane

Abd uc t the toe s from the sec on d toe,flexthe meta tarsophala ngeal joints,a ndextendthe interphalangea l joints Add uc t the toe s to the sec on d toe , flexthemetatarsophalangeal joints,andextendthe inte rph ala nge al join ts Plan tar flexes the foo t at the an kle joint, e verts the foot a t the subtala randth etransversetarsal joints, a nd ho lds u p th e la tera l longitudinal a nd the transverse arche s of the foot Plan tar flexes the foo t at the an kle joint,invertsthefootatthe subta larandthetran sverseta rsal joints, a nd supports the media l longitudinal a rch o f the foot


inguinal ligament external iliac artery femoral artery profunda artery lateral femoral circumflex artery

medial femoral circumflex artery femoral artery perforating branches of profunda femoris artery

popliteal artery

posterior tibial artery

peroneal artery anterior tibial artery

dorsalis pedis artery

arcuate artery

Figure 5-18 Major arteri es of the lower

limb .

• Superficial circumflex iliac artery,which a rises just below the inguinal l igame nt and runs laterall y toward the anterior superior ili ac spine. • Superficial epigas tric ar tery, which a rises just below the inguinal l igame nt and run s upward to the abd omina l wall.

ment and run medially to supply the skin of the scrotum (or labium m ajus). • Profunda femoris artery,which is a large branch that arises from the femo ral artery approximately 1. 5 in. (4 c m) be low the inguin al ligamen t ( Fig. 5-12). It sup plie s stru ctures in the anterior, medial, and posterior fascial compa rtme nts o f the thigh via th e followin g bra nc he s: medial

• Superf icial e xternal puden dal artery. • Deep external pudendal artery and the superficial external pudendal artery arise just below the inguinal liga-

and lateral femoral circumflex arteries and four perforating arteries. • Descend ing genicular art ery.

BRANCHES

CHAPTER 5

TROCHANTERIC ANAS TOMOSIS The trocha nteric anastomo sis provides the ma in blood supply to the he ad of the femu r (in ad ults) via the following arteries: • Supe rior gluteal art ery. • Inferior gluteal artery. • Medial femoral cir cum flex artery . • Lateral f emo ral circum flex artery .

CRUCIATE ANASTOMOSIS Together with the trochanteric anastomosis, the cruciate anastomosis provides the important connection between the internal iliac and the femoral arteries. The following arteries are involved: • • • •

Inferior gluteal artery. Medial femoral cir cum flex artery . Lateral f emo ral circum flex artery . First perforati ng artery , which is a branc h of the profunda artery.

Popliteal Artery The popliteal artery (Fig. 5-18) is a continuation of the femo ral artery . It extends from the op ening in the a ddu ctor magnu s to the lower border of the pop liteus muscle, where it divides into the anterior an d the posterior ti bial arteries. I t is deeply placed in the popliteal fossa and lies close to the po sterio r surfac e o f the fem ur a nd the kne e join t.

BRANCHES • Muscular branches. • Articular branches to the knee joint. • Terminal branches: Anterior and posterior tibial arteries.

Lower Limb

18 7

At the ankle, the anterior tibial artery lies midway between the malleoli and has the tendon of the extensor hallucis longus muscle on its med ial side an d the ten don s of extensor digit orum longus muscle o n its lateral si de (the site for taking an anterior tibial pulse).

BRANCHES • Muscular branches. • Anastomotic branches, which anastomose with b ra n ch e s of oth er arte rie s a ro un d th e kn e e an d an kle joints.

Dorsalis Pedis Artery The dorsalis pedis artery begins in front of the ankle joint midway between the malleoli and is a continuation of the anterior tibial artery (Figs. 5-9 and 5-18). The dorsalis pedis artery end s by entering t he sole through the proximal part of the space between the first and second metatarsal bones. Having passed b etween the two he ads o f the first dorsal i nterosseous muscle, it joins the lateral plantar artery and com pletes the plantar a rch (Fig. 5-16). At first, the a rtery is supe rficial, having the tend on s of the extensor digi torum longus mu scle on its lateral s ide an d the tendo n of the extensor hallucis l ongus muscle on its med ial side (the site for taking a dorsalis pedis pulse ).

BRANCHES • Lateral tarsal artery,which supplies the dorsum of the foot. • Arcuate artery, which runs laterally across the bases of the me tatarsal bones an d gives off branc hes to the toe s. • First dorsal metatarsal artery, which supplies both sides o f the big toe.

Poste rior T ibial Artery

ANASTOMOS IS AROUND THE KNEE JOINT

The posterior tibial artery arises at the bifurcation of the

The a rteries involv ed in ana stomosis ar oun d the knee joint are as follows:

po plite al a rtery in the po plitea l fossa ( Fig. 5-18). It desc en ds in the posteri or comp artment of t he leg and is accom pan ied by the tibia l ne rve. The a rtery term ina tes b eh ind the me dia l malleolus by div iding into the med ial and the lateral plantar arteries. The p ulse may be felt midway between the med ial malleolus and the hee l.

• The d escen ding genicu lar artery from the femoral artery . • The lateral f emo ral circum flex artery from the profund a femoris. • The articular branche s from the pop liteal art ery. • The b ranche s from the anterior and the po sterior t ibial arteries.

BRANCHES

The anterior tibial artery arises at the bifurcation of the po plite al arte ry in the p op litea l fossa ( Fig. 5-18). It pa sses forward between the tibia and the fibula through the upper pa rt of the inte rosse us me mb ran e an d en ters the an terio r

• Peroneal art ery,which is a large artery that arises close to the srcin of the posterior tibial artery. It descends in close association with the flexor hallucis longus muscle to the regi on o f the a nkle, and it gi ves of f muscular branches, a nutrient artery to the fibula, and anastomotic branches around the ankle joint. • Muscular branches.

com partmen t of the leg. It then d escen ds with the deep p erone al nerve to the fr ont of the ankle joint, where it beco mes the do rsalis pedis arte ry (Fig. 5-9).

• Nut rient arteryto the tibia. • Anast omotic branche around the ankle joint. s • Medial and lateral plantar arteries.

Anterior Tibial Artery


Medial Planta r Artery

VEINS OF THE LOWER LIMB

The medial plantar artery is the smaller of the terminal bran ch es of the posterior tibial artery (Fig. 5-16). It runs forward along the medial border of the foot with the medial plantar nerve, and it gives off man y muscular and cutan eou s branch es.

The superficial veins lie in the superficial fascia and are of great cli nical impor tance. The deep veins acc ompan y the main arteries.

Lateral Plantar Artery

Superficial Veins

The lateral plantar artery is the larger of the terminal bra nc he s of the po sterio r tibia l arte ry (Fig. 5-16). It run s forward dee p to the abd uctor hallucis and the fl exor digi torum bre vis musc les with th e la tera l plan tar n erve , an d it e nd s by curving medially to form the plantar arch through anastomosis with the dorsalis pedis artery. The plantar arch gives off perforati ng an d metatarsal arteries; t he metatarsal arteries give rise to digital arteries.

DORSAL VENOUS NETWORK The dorsal venous network lies on the dorsum of the foot (Fig. 5-19). It is drained on the medial side by the great saphenous vein and on the lateral side by the small saphenou s vein.

GREAT SAPHENOUS VEIN

CLINICAL NOTES COMPRESSION LOWER LIMB

OF ARTERIES OF THE

Medica l personal should know the precise position of the m ain arteries wi thin the lower limb. • Femo ral artery:This enters the thigh behind the inguinal ligament at a point midway between the anterior supe rior iliac spine an d the symphysi s pub is. • Popliteal artery: This artery can be felt by gentle pa lpa tion in the de pth s o f the po plite al spa ce , p rovided that the deep fascia is fully relaxed by passively flexing the knee joint. • Dor salis pe dis artery:This artery lies between the tendons of the extensor hallucis longus and the extensor digitorum longus, midway between the medial and lateral mall eoli on the front of t he a nkle. • Posterior tibial artery:This artery passes behind the medial malleolus, beneath the flexor retinaculum, and lies between the tendons of flexor digitorum longus and the flexor hallucis longus. The pu lsation s of the a rtery ca n b e felt midwa y be twee n the medial malleol us and the heel.

CLINICAL NOTES LIGATION

OF ARTERIES OF THE LOWER LIMB

Sudd en occ lusion of the femoral artery by li gature is usually followed by gangrene. However, gradual occlusion , such as oc cu rs in ath erosc lerosis, is less likely to be followed by necrosis because the collateral blo od vessels ha ve tim e to dila te fully. The co llate ral circulation for t he proximal part of the femoral artery is through the cruciate and troch anteric ana stomoses; for the femoral artery in the adductor canal, it is through the perforating branches of the profunda femoris artery and the articular and muscular bra nc he s of the femo ral a nd po plite al a rterie s.

The great sap hen ous vein arises f rom the med ial side of the dorsal venous network of the foot ( Fig. 5-19), a nd it ascend s directly in front of the medial malleolus. Accompanied by the saph eno us nerve, it ascends the leg in the superfi cial fascia, passes beh ind the knee, and c urves forward around the medial side of the thigh. It then passes through the saphenousroximately opening in1.5 thein. deep fascia and joins femoral app (4 cm) b elow and the lateral t o thevein pu bic tubercle. The great saphenous vein possess numerous valves, and it is connected to the small saphenous vein by bra nc he s tha t pa ss be hin d the kne e. Severa l perforating veins conne ct the great saphenous vein wi th the de ep veins along the me dial side of the c alf. The great saphenous vein receives the following small tributaries n ear its termination: • The superficial cir cumflex iliac ve in. • The superficial epigastr ic ve in. • The superficial external pudendal vein.

CLINICAL NOTES THE CLINICALIMPORTANCE OF THEGREAT SAPHENOUSVEIN • Blood transfusions: The constant position of the great saphenous vein in front of the medial malleolus should be remembered for patients requiring emergency blood transfusion. • Bypass operations: The insertion o f a graft of a p ortion of the great saphenous vein can be used in occlusive coronary artery disease and also to bypass obstructions of the brac hial or femoral arteri es.

SMALL SAPHENOUS VEIN The small saphen ous vein a rises from the lateral side o f the dorsal venous network of the foot (Fig. 5-19). It ascends behind the lateral malleolus in company with the sural nerve, passes up the back of the leg, and pierces the deep

CHAPTER 5

Lower Limb

superficial circumflex iliac vein

saphenous opening femoral vein

superficial epigastric vein pubic tubercle

femoral artery

great saphenous vein access ory vein

superficial external pudendal vein great saphenous vein

popliteal vein

small saphenous vein

perforating vein muscle lateral malleolus

superficial fascia skin

medial malleolus venae comitantes

saphenous vein deep fascia dorsal venous arch

"Venous pump" Figure 5-19 Sup erfi cial veins of the vei ns in the “venou

s pum p.”

right lowe r limb . Note the imp ortance of the valved p

erforati ng

18 9


fascia to e nter the p opliteal f ossa. It drains into the pop liteal vein. The small saphenous vein communicates with the deep veins and with the great saphenous vein. The superficial veins of the lower limbs are com mon sites for varico sities.

level of the um bilicus, the p erineum , the external genitalia in both sexes (but not the testes), and the lower half of the anal canal. It also receives lymph from the skin of the bu ttoc ks.

VERTICAL GROUP

Deep V ein s

The vertical group lies alongside the terminal part of the

VENAE COMITANTES

great and receives the the superficial lymphsaphenous vessels ofvein the lower li mb (emost xceptof fr om bac k and lateral si de of the ca lf and the lateral side o f the foot, which drain into the popliteal nodes).

The d eep veins acc omp any the respective arter ies as vena e comitantes. The venae comitantes of the anterior and the po sterio r tibia l a rterie s un ite in the po plite al fossa to form the po pliteal vein.

POPLITEAL VEIN The p opliteal v ein is formed by the union of the venae c omitantes of the a nterior and the p osterior tibial arteri es ( Fig. 514). It end s by pass ing through the o pen ing in the ad duc tor magnus muscle to become the femoral vein. The popliteal vein receives numerous tributaries, including the small saphenous vein.

Deep Inguinal N ode s The d eep inguinal nod es are usually three in num ber and lie along the me dial side of the femoral vein and in the femoral canal. They receive all the lymph from the superficial inguinal node s and the dee p structures of the lower li mb . The efferent lymph vessels pass upward through the femoral canal into the abdominal cavity, and they drain into the external il iac no des.

Popliteal L ymph Node s FEMORAL VEIN The femoral vein is a continuation of the popliteal vein at the ope ning i n the addu ctor magnus muscle. I t ascends through the adductor canal and the femoral triangle and is acc omp anied by the femoral artery . In the femo ral sheath, it lies on the me dial side of the femo ral artery and on the lateral side to the femoral canal. As it ascends behind the inguinal li gamen t, it bec ome s continuo us with the external il iac vein. T he femoral vein receives the great saphe nou s vein and the veins that correspond to branches of the femoral artery.

LYMPHATIC DRAINAGE OF THE LOWER LIMB The superficial lymph vessels ascend the limb in the supe rficia l fascia with th e sup erficia l vein s. The deep lymph vessels lie deep to the deep fascia and follow the deep arteries an d veins. All the lymph vessels of the lowe r limb ultimately drain into the dee p inguinal gr oup of nodes that are situated in the groin.

Superficial Inguinal Nodes The superficial inguinal nodes lie in the superficial fascia just be low th e in guin al ligam en t an d d rain into the de ep inguinal nodes. The superficial inguinal nodes may be divided into a ho rizontal an d a vertical group .

HORIZON TALGROUP The horizontal group receives lymph from the superficial lymph vessels of the anterior abdominal wall below the

Situated in the pop liteal fossa, the po pliteal lymph n ode s receive the superficial lymph vessels that accompany the small saphenous vein from the lateral side of the foot and from the bac k and the lateral side of the c alf. They also receive lymph from the deep structures of the leg below the knee. The eff erent vessels f rom the se no des d rain upwa rd to the deep inguinal nodes.

NERVES OF THE LOWER LIMB Fe moral Nerve The femo ral nerve arises f rom the lumba r plexus ( L2, 3, and 4). It enters the thigh behind the inguinal ligament, and it lies lateral to the femo ral vess els and the femoral shea th in the femoral triangle (Fig. 5-12). It quickly terminates by dividing into the anterior an d the posterior div isions.

BRANCHES OF THE FEMORAL NERVE IN THE THIGH • Cutaneous branches: Medial cutaneous ne rve of t he thigh, which supplies the skin on the medial side of the thigh. Intermediate cutaneous nerve of the thigh, which supplies the skin on the anterior surface of the thigh. Saphenous nerve, which descends through the femoral triangle and the adductor canal and crosses the femoral artery. The nerve emerges on the medial side of the knee joint between the tendo ns of the sartori us and the gracilis muscles, and it acco mpa nies the gr eat saphe nou s vein down the med ial side of the leg and in front of the medial malleolus. It passes along the medial border of the foot a s far as the ball of the b ig toe. • Muscular branches to the sartorius, the pectineus, and the qua driceps f emo ris muscles. • Articular branches to the hip and knee joints.

CHAPTER 5

Lower Limb

19 1

Femoral nerve L2 L3 L4 Abdomen

Lumbar plexus iliacus pectineus hip joint

sartorius

Front of thigh

quadriceps femoris knee joint femoral artery

intermediate cutaneous nerve of thigh

saphenous nerve

medial cutaneous nerve of thigh

branch to subsartorial plexus infrapatellar branch to skin Lower leg

to skin of medial side of leg

Foot

skin on medial side of foot as far as ball of big toe

Figure 5-20 Sum mary of the main branches of the femoral nerv

The branches of the femoral nerve are summarized in Figure 5-20. Dermatomal charts for the anterior and posterior surfac es of the b od y are sho wn in Figures 2-3 and 2-4.

Obturator Nerve The obturator nerve arises from the lumbar plexus (L2, 3, and 4) an d run s forward on the lateral wall of the p elvis to reach the o bturat or canal ( the uppe r part of the obturator forame n) . The o bturator nerve divi des into the an terior and the posterior divisions.

e.

The posterior division descends through the ob turat or exter nus muscle and passes behind the adduc tor brev is and in front of t he ad duc tor magnus muscles. • Muscular branches: Obturator externus, adductor magnus (ad ductor part), and sometimes the add uctor brev is muscles. • Articular branch Kne : e joint. The branches of the obturator nerve are summarized in Figure 5-21. Dermatomal charts for the anterior and the posterior surfaces o f the bo dy are shown in Figures 2-3 and 2-4.

BRANCHES OF THE OBTURATOR NERVE IN THE THIGH

Sciatic Nerve

The anterior division descends into the thigh anterior to the obturator externus and the adductor brevis muscles. • Muscular branches:Gracilis, add uctor b revis, addu ctor

The sciatic n erve arises f rom the sacral plexus ( L4 and 5 and S1, 2, and 3). It passes out of the pelvis and into the gluteal region through the greater sciatic foramen (Fig. 5-11). The

longus, and sometimes the pectineus muscles. • Cutaneous branch:Skin on the med ial side of the thigh. • Articular branch:Hip joint.

nerve appears below the piriformis muscle and is covered by the glute us ma ximus mu scle . It d esc en ds thro ugh the gluteal region, and it enters the posterior compartment of


Obturator nerve L2 L3 L4

Abdomen

Lumbar plexus

peritoneum on lateral wall of pelvis Pelvis

posterior division

anterior division

hip joint pectineus ? Adductor region of thigh

adductor magnus (adductor portion) adductor brevis

adductor longus adductor brevis

gracilis subsartorial plexus with medial cutaneous nerve of thigh and branch

knee joint

popliteal artery

of saphenous nerve femoral artery Figure 5-21 Sum mary of the main branches of the obturator nerve.

the thigh. I n the lower third of the thigh (an d oc casionally at a higher level), it ends by dividing into the tibial and the com mon peron eal ne rves ( Fig. 5-13).

BRANCHES OF THE SCIATIC NERVE • Muscular branches: Biceps femoris (long head), semitendino sus, semimem brano sus, and ham string part of the addu ctor magnus muscles. • Articular branches:Hip joint. • Terminal branche s: Tibial and comm on p eroneal nerves.

Tibial Nerve The tibial nerve descends through the popliteal fossa and the po sterior com partmen t of the leg. I t lies de ep to the gastrocnemius and soleus muscles, and it reaches the interval be twee n th e m ed ial ma lleo lus an d th e h ee l. It is co vere d b y the flexor retinaculum and divides into the medial and the lateral plantar n erves.

• Muscular branches: Gastrocnemius, plantaris, soleus, po plite us, flexo r d igitorum lon gus, flexo r h allu cis lo ngu s, and tibialis posteri or m uscles. • Articular branches:Knee and ankle joints . • Medial plantar nerve:Runs forwar d d eep to the abd uctor hallucis muscle with the med ial plantar artery (Fig . 516). Cutaneous branch,which supplies the medial part of the sole and the medial three and a half toes and nail be ds. Muscular branc h,which supplies the abd uctor hallucis, flexor digitorum brevis, flexor hallucis brevis, and first lumbrical muscles. • Lateral plantar nerve:Runs for ward deep to the ab ductor hallucis and flexor digitorum brevis muscles in compa ny with th e late ral pla nta r arte ry (Fig. 5-16). Cutaneous branch, which supplies the lateral part of the sole an d the lateral one and a half toes and nail beds. Muscular branch, which sup plies the flexor dig itorum ac cessorius, abductor digiti minimi, flexor digiti minimi brevis, adductor hallucis, i nterosseous mu scles, s eco nd lumbrical, third lumbrical, and fourth lumb rical muscles.

BRANCHES OF THE TIBIAL NERVE • Cutaneous Bra nche s: Sur al nerve(joined by communicating branch of the common peroneal nerve), which supplies the ski n o f the c alf, the ba ck of the leg, the lateral bo rde r of the foo t, an d th e late ral side of the little to e ( Fig. 5-14). Medial calcaneal nerve, which sup plies the skin over the me dial surface of the h eel.

Commo n Peron eal Nerve The common peroneal nerve descends through the po plite al fossa (Fig. 5-14). It the n pa sses late rally aro un d the nec k of the fibula, pierces the pe roneu s longus muscle, and divides into the superficial and the deep peroneal nerves.

CHAPTER 5

Lower Limb

• Deep peroneal nerve: Descends in the anterior fascial compartment deep to the extensor digitorum longus Cutaneous branches: Sur al communicating branch muscle and on the interosseous membrane (Fig. 5-9). It (Fig. 5-9), which joins the sural ne rve ( see Branch es of the is accompanied by the anterior tibial vessels, and on the Tibia l Nerve) . Lateral cutaneo us ne rve of the calwhich f, dorsum of the foot, it divides into the medial and the supplies t he skin on the lateral si de of the bac k of the leg. lateral terminal branches. Cutaneous branch, which Muscular branch: Short head of the biceps femoris suppies the adjacent sides of the big and the second muscle. toes. Muscular branch, which supplies the tibialis anArticular branch:Kne e joint. Descends between the perterior, extensor digitorum longus, peroneus tertius, exSuperf icial peroneal ne rve: tensor hallucis longus, and extensor digitorum brevis one us longus and brevis muscles in the lateral fas cial com muscles. Articular branch, which supplies the ankle pa rtmen t an d be co me s sub cu tan eo us ( Fig. 5-9). Cutaand tarsal joints. neous bra nchto the skin on the front of t he lower leg and The branches of the sciatic nerve are summarized in dorsum o f the foot (exce pt for the cleft betwee n the b ig and Figures 5-22 and 5-23. Dermatomal charts for the anterior the second toes, w hich is i nnervat ed by the deep peroneal and the po sterior surface s of the b ody are sho wn in Figures nerve). Muscular branch, which suppli es the peroneus 2-3 and 2-4. longus and brevis muscles.

BRANCHES OF THE COMMON PERONEAL NERVE •

• • •

19 3

Sciatic nerve L4 L5 S1 S2 S3

Pelvis

sciatic nerve

Sacral plexus

tibial nerve

Gluteal region


Back of thigh

biceps femoris (short head) lateral cutaneous nerve of calf

knee joint sural communicating branch

deep peroneal nerve tibialis anterior

peroneus longus

extensor hallucis longus extensor digitorum longus

Lower leg

superficial peroneal nerve

peroneus brevis

peroneus tertius skin of lateral side of leg

skin of lateral side of foot Foot

skin of leg

ankle joint

extensor digitorum brevis

skin of dorsum of foot

skin of cleft between first and second toes

Figure 5-22 Sum mary of the m

ain branches of the comm

on pe roneal nerve and

ori gin of t he s ciati c nerve.


Sciatic nerve Pelvis

Sacral plexus

L4 L5 S1 S2 S3

tibial nerve

sciatic nerve

Gluteal region


hip joint semitendinosus biceps femoris (long head) semimembranosus adductor magnus (hamstring part)

Back of thigh

knee joint gastrocnemius sural nerve

soleus plantaris popliteus tibialis posterior flexor digitorum longus flexor hallucis longus skin of ankle ankle joint

Lower leg

medial plantar nerve Sole of foot

lateral plantar nerve skin of sole of foot

adductor hallucis

joints of foot

flexor digitorum brevis

flexor digitorum accessorius flexor hallucis brevis

skin of sole of foot

abductor digiti minimi flexor digiti minimi brevis

first lumbrical second, third, fourth lumbricals abductor hallucis all interossei Figure 5-23 Sum ma ry of the m ain branche s of the ti bial nerve a nd srcin of the sciati c nerve.

SCIATICNERVELESIONS CLINICAL NOTES

Stab or gunshot wounds in the thigh are common cau ses of femo ral nerve lesions, but the n erve is rarel y completely divided. In those with such lesions, the qua driceps femoris muscle is paraly zed, and the knee

Badly placed intramuscular injections in the gluteal region, fracture disl oca tions of t he hip joint, and pen etrating wounds may damage the sciatic nerve. In those with such lesions, the hamstring muscles are pa ralyzed so tha t flexion of th e kne e is grea tly wea kened. All the muscles below the knee are also paralyzed, and the weight of the foot causes it to assume

cannot be extended. There is also sensory loss over the me dial side o f the lower part of the leg and a long the medial border of the foot as far as the ball of the big to e.

the plantar-flexed position (foot drop). There is loss of skin sensati on b elow the knee ( excep t for a na rrow pa rt of the le g an d th e m ed ial b ord er o f the foot a s far as the ba ll of the big toe) .

FEMORALNERVELESIONS

CHAPTER 5

REVIEW

Comp letion Ques tions Based on the anteroposterior radiograph of the hip region, select the phrase that best completes each s tatement.

Lower Limb

4. Structure 4 i s the A. supe rior r amu s of pubi s. B. bo dy of pu bis. C. lesser t roc han ter. D. ischi al t uber osity. E. isch ial ram us. F. Non e o f the ab ove. 5. Structure 5 i s the A. lesser sciatic foramen. B. greater sciatic foramen. C. sub pu bic an gle. D. obt urator foram en . E. fovea c ap itis. F. Non e o f the abo ve. Based on the anteroposterior radiograph of the knee joint, select the phrase that best completes each s tatement.

1. Structure 1 i s the A. ne ck of the femu r. B. mar gin of obt urator foramen. C. D. E. F.

acetabulum . iliope ctineal line. lesser t roc ha nter. Non e o f the ab ove.

2. Structure 2 i s the A. he ad of fem ur. B. iliope ctineal line. C. ischi otuber osity. D. lesser trocha nter. E. ne ck of the fem ur. F. Non e o f the ab ove. 3. Structure 3 i s the A. great er troch ant er. B. lesser trocha nter. C. ischi al t uber osity. D. E. F.

acetabu lum. isch ial ram us. Non e o f the ab ove.

6. Structure A i s the A. he ad o f the fibul a. B. medi al condy le of the femur . C. site o f the epi phy seal line. D. E. F.

lateral condy le of the ti bia. intercon dylar emi nen ce. Non e o f the ab ove.

19 5


7. Structure B i s the A. intercon dylar emi nenc e. B. medi al cond yle of tibia. C. tibial tuber osity. D. lateral m eni scu s. E. ant erior cruci ate ligament . F. Non e o f the ab ove.

11. Structure 1 is the A. calcane um. B. lateral mal leolus. C. bo dy of talus. D. na vicu lar. E. med ial ma lleo lus. F. Non e o f the ab ove.

8. Structure C i s the A. me dial me niscu s. B. lateral condy le of tibia. C. lateral condy le of femur . D. intercon dylar emi nenc e. E. site of epi phy seal line. F. Non e o f the ab ove.

12. Structure 2 is the A. cuboid. B. med ial cu ne iform. C. na vicu lar. D. he ad of talus. E. intermedi ate cu nei form. F. Non e o f the ab ove.

9. Structure D i s the A. lateral condy le of tibia. B. ne ck of the fibul a. C. super ior tibiofibul ar joint . D. co mmo n pe ron eal ne rve. E. he ad of the fibul a. F. Non e o f the ab ove.

13. Structure 3 is the A. sustent acu lum t ali. B. ne ck of the talus. C. na vicu lar. D. calcaneu m. E. lateral mal leo lus F. med ial ma lleo lus.

10. Structure E is the A. site of epi phy seal line. B. C. D. E. F.

styloid proces s of head of fibul a. lateral condy le of tibia. attachment of medial collater al ligament . articular surface of head of fibul a. Non e of the a bo ve.

Based on the la teral radiograph of t he ankle region, se lect the phrase that best completes ea ch sta tement.

14. Structure 4 is the A. med ial mal leo lus. B. C. D. E. F.

bo dy of talus. lateral mal leol us. ne ck of the talus. cuboid. Non e o f the ab ove.

15. Structure 5 is the A. na vicu lar. B. med ial cu ne iform. C. tuber osity of the nav icul ar. D. calcaneu m. E. insertion of the tendo c alcaneus . F. Non e o f the abo ve. Select the phr ase that best completes eac h statemen t.

16. Flexion of the hip j oint (with t he knee e xtende d) is limited by the A. iliofemor al ligament . B. ant erior abdo minal wall. C. ischi ofemor al ligament . D. pubo femo ral ligamen t. E. ant erior super ior iliac sp ine. F. Non e o f the ab ove. 17. Abdu ction of t he hip joint i s limited by the A. pe ctineu s mus cle. B. iliofemor al ligament . C. ischi ofemor al ligament . D. pubo femo ral ligamen t. E. ligament of the head of the femur . F. Non e o f the ab ove. 18. Extension of t he h ip joint is limited b y the A. iliofemor al ligament . B. C. D. E.

pubo femo ral ligamen t. ischi ofemor al ligament . qu adr ice ps mus cle. add uct or mag nus mu scle.

CHAPTER 5

19. Flexion of t he h ip joint (with the knee flexed) by th e A. hams tring mus cles. B. iliofemor al ligament . C. add uc tor m agnu s mu scle. D. pubo femor al ligamen t. E. ant erior abdo minal wall. F. ischi ofemo ral l igamen t.

is limited

20. The long head of the b iceps f emoris muscl e is innervated by the A. obt urator ne rve. B. tibial port ion of the sciatic nerv e. C. fem oral ne rve. D. co mmo n pe ron ea l ner ve. E. sural ne rve. 21. The gracili s muscle is innervated by the A. fem oral ne rve. B. co mmo n pe ron ea l ne rve. C. sural ne rve. D. obt urator ne rve. E. tibial port ion of the sciatic nerv e. 22. The gluteus maximus muscle is innervated by t he A. inferior gluteal ner ve. B. C. D. E.

ner ve to qua dra tus femor is. obt urator ne rve. super ior gluteal ner ve. ner ve to obtu rator internus .

23. The sartori us muscle is innervated by the A. obt urator ne rve. B. fem oral ne rve. C. ner ve to vastus medi alis. D. super ior gluteal ner ve. E. lateral cu tan eous ner ve of the thi gh. 24. The ha mstring port ion of t he a dductor magnus muscle is inne rvated by the A. co mmo n pe ron ea l n erve. B. tibial port ion of the sciatic nerv e. C. obt urator ne rve. D. E.

femo ner veral to tne herve. pec tineu s mu scle.

25. The ad ductor longus mus cle is i nnervat ed b y the A. fem oral ne rve. B. co mmo n pe ron ea l ne rve. C. tibial port ion of the sciatic nerv e. D. anter ior division of the obtu rator ner ve. E. post erior di vision of the obt urat or ner ve. 26. A malig nant melanoma (ca ncer) of the sk in cover ing the b uttock is li kely to sprea d via lymphatics to the A. hori zont al group of super ficial inguinal nodes. B. vertical group of s uperf icial inguinal nodes. C. pos terior axillary nodes . D. po plitea l no des . E. internal iliac node s. 27. Lymph from the na il be d of the b ig toe drains into t he A. hori zont al group of super ficial inguinal nodes. B. presac ral no de s. C. po plitea l n od es.

D. E.

Lower Limb

19 7

internal iliac node s vertical group of s uperf icial inguinal nodes.

28. The lateral menis cus of t he knee joint A. has a thick inner bor der . B. is strong ly attached around it s circumf erence to the tibia. C. is more f requent ly torn t han the medi al meni scus . D. is strong ly att ached to the l ater al col lat eral ligament. E. is attached by it s ant erior hor n to the t ibia in f ront of the intercondylar eminence. 29. Lymph from the skin of the lateral si de o f the foot drains into the A. po pliteal no des . B. internal iliac n odes . C. vertical group of s uperf icial inguinal nodes. D. hori zont al g roup of s uperf icial inguinal nodes. E. subs artorial n od es. 30. Lymph fr om the skin of t he m edial side of t he kne e drains into the A. po pliteal no des . B. vertical group of s uperf icial inguinal nodes. C. medial g roup of t he horiz ontal s uperf icial ingu inal nodes D. internal iliac no des . E. later al group of hori zont al inguinal nodes . 31. Lymph f rom the ski n around the anus d rains int o the A. internal iliac no des . B. inferior mes ent eric no des . C. lat eral g roup of hor izontal s uperf icial i ngui nal nodes. D. medial g roup of hori zont al s uperf icial i ngui nal nodes. E. vertical g roup of i nguinal no des .

Multiple-Choice Questions Select the best answer for each questi on.

32. The sciat ic nerve enters the gluteal r which foramen? A. Posterior s acr al B. Grea ter sciatic C. Anterior sac ral D. Lesser sciatic E. Obturator

egion through

33. The comm on peroneal nerv e can be palpated in w hich region o f the knee ? A. As it winds around t he medial side of the neck of the fibula. B. As it pas ses around t he medial condyl e of t he ti bia. C. As it winds around t he lat eral side of t he neck of the fibula. D. E.

As it pas ses forw ard betw een the t ibi a and the fibula. As it cr oss es t he lat eral side of t he head of t he fibula.


34. If the dorsalis pedis artery i s severed just proxi mal to its med ial and lateral tarsal branc hes, blood ca n still reach the d orsum of the foot through which vess el(s)? A. The p erone al artery. B. The post erior t ibial ar tery. C. The medi al plant ar artery. D. The lat eral pl ant ar ar tery. E. All of the abo ve. 35. In children, the chief art erial supply to the hea d of the femur is derived from which artery or arteries? A. The obt urator ar tery. B. The i nternal pudendal artery. C. Branches from t he medial and lat eral circumf lex femoral arteries. D. The deep ci rcumf lex iliac artery. E. The superf icial cir cumf lex i liac arter y. 36. Which statement is corr ect con cerning t he femoral ri ng? A. It is the opening in the deep fas cia of the t high for the great saphenous vein. B. It is the openi ng in the adductor magnus muscl e for the femoral artery. C. It is the prox imal opening in the femoral canal. D. It is the compart ment i n the f emoral sheat h for the femoral artery. E. It is the compart ment i n the f emoral sheat h for the femo ral nerve. 37. To lift the left foot o ff the groun d wh ile walking, which of the following muscles plays an imp ortant role? A. The lef t gluteus med ius mus cle B. The lef t gluteus max imus mus cle C. The ri ght add uct or long us mu scle D. The right gluteus medius muscl e E. Non e o f the ab ove. 38. Rupture of t he tend o calca neu s results in an inabilit y to do what? A. Dorsiflex the foot B. Evert the foo t C. Invert the foo t D. Plant ar flex t he f oot E. Non e o f the ab ove. 39. A sprained a nkle result ing from exce ssive evers ion mo st likely demo nstrates that which structure is torn? A. The t alofibul ar ligament B. The t en do c alca ne us C. The del toid ligamen t D. The i nterosseous ligament E. The p erone al retinacu lum 40. If the foot is permane ntly dorsi flexed and which ne rve might be injured? A. The d eep per onea l ner ve B. The sup erficial per oneal ner ve C. The c ommo n pe rone al ner ve D. E.

The ibial ner ve The tob turator ne rve

evert ed,

41. The femoral ne rve arises f rom which o f the following segments of t he spina l cord? A. L2 and 3 B. L4 and 5 and S 1, 2, and 3 C. L2, 3, an d 4 D. L1 and 2 E. L5 an d S1, 2, an d 3 42. The d ermatome p resent over the later al side of the foot is which o f the following? A. S5 B. L3 C. S1 D. L4 E. L5 43. The femoral sheath is f ormed by which of the following layer(s) of fascia? A. The pe ctineus fascia B. The fas cia i liaca and the f asci a trans versalis C. The fascia lat a and the membr anous l ayer of the supe rficial fascia D. The psoas f ascia and the fatt y layer of superf icial fascia E. The proces sus vaginal is 44. Which o f the followi ng muscles everts the foot? A. The tibialis post erior muscl e B. The flexor hallucis long us muscl e C. The per oneu s long us m uscle D. The ti bialis ant erior mus cle E. The flexor digitorum l ongus muscl e 45. Injury to the comm on p eroneal nerve res ults in whi ch condition? A. Inabil ity to invert the foot B. Inabil ity to pl antar flex the ankl e C. Inabil ity to feel skin sens ation on the medial side of the leg D. Inabil ity to plant ar flex the big toe E. Inabi lity to e vert the foot 46. After a lesion of the tibial part of t he sciatic ne rve, some active flexion may still be possible at the knee joint; the muscles respon sible for this remaining fl exion inc lude which? A. The shor t head of the bi ceps f emori s mus cle B. The g astrocne mius mu scle C. The p lant aris mus cle D. The p opl iteus mus cle E. The long head of the bi ceps femori s muscl e 47. A patient i n the supine posit ion wi th the hip and knee join ts e xte n d e d is a ske d to ab d uc t th e low e r lim b against resi stance provided b y the ph ysician; this exercise tests which of the following muscles? A. The semitendi nos us mus cle B. The g luteus medi us mu scle C. The pe ctineu s m uscle D. The g raci lis mus cle E. The s emi membr anos us mus cle

CHAPTER 5

48. A femo ral hernia has the foll owing charac teristics except which? A. It is mor e common i n wo men t han i n men. B. The sw elling occurs below and lat eral to the pubic tubercle. C. It des cends through the f emor al ca nal . D. Its neck is rel ated immediat ely lat eral ly to the femoral artery. E. Its neck i s relat ed medial ly to the shar p edge of the lacunar ligament. 49. The gastr ocnem ius and the soleus muscles hav e all the following features in comm on except which? A. They are s uppl ied by the t ibial nerv e. B. They are found in t he post erior compa rtment of the leg. C. They ar ise from the f emoral condyl es and f lex the knee joint. D. They insert via the tendo cal caneus. E. They plantar flex the ankl e joint . 50. All the followi ng statements ab out the sartorius muscle are correct exc ept which? A. B. C. D. E.

It flexes flexes the the thi leggh at at thethe knee oint .. It hi pj joint It lateral ly rotat es the thi gh at the hip joint. It adduct s the thi gh at the hi p joint. It attaches to the anter ior super ior iliac s pine.

51. The foll owing s tructures are transmit ted through the lesser sciati c forame n except which? A. The tendon of the obtur ator internus muscl e B. The i nternal pudenda l vessels C. The nerv e to the obtur ator internus muscl e D. The pu den dal ne rve E. The inf erior g luteal ar tery 52. The following statements reg arding the g reat sapheno us vein are correct exc ept which? A. B. C. D. E.

It arises on t he dors um of the foot. It ent ers the l eg by pass ing anter ior to the medial malleolus. It drains into the femoral v ein approxi mately 1.5 in. (3.8 cm) below and lateral t o the p ubic tubercle. It is acc ompani ed by t he sap henous ner ve. It has no communi cat ion wi th the deep v eins of the leg.

53. The following s tatemen ts regarding t he o bturator nerve are correct exc ept which? A. It originat es from t he lumbar plex us. B. It ent ers the thi gh i mmedi ate ly beneat h the inguinal lig ame nt. C. It innerv ates the adductor muscl es of the t high. D. E.

It suppl divides anteri ormedial and a post division. It iesinto the san kin on the s ideerior of the t high.

Lower Limb

19 9

Read the cas e histor ies and se lect the best answer to the ques tion following them.

After a football injury, an orthopedic surgeon noted that the right tibia of the patient could be m oved a nteri orl y wit h excessive f reedom when the knee wa s flexed. 54. In this patient, whi ch ligament is most li kely to be torn? A. The later al collater al ligament B. The pos terior cr uci ate ligament C. The ant erior cruci ate ligament D. The medi al co llateral ligament E. The pat ellar ligamen t A 69-year-ol d m an was walk ing dow n a flight of steps when he slipped and fell. On impact, his left foot hit the gro und and was forcibl y inverted and medially rotated. He stated that he felt som ethi ng g ive on the lateral side of the dorsum of the foot. Though shocked by the fall and the resulting foot pain, he was able to walk home. Within 2 h, the left foot and ankle had swollen considerably, which made examination by his p h ys icia n d ifficu lt. M o ve m e n ts o f th e a n kle w e re clearly possible, but inversion was extremely p a in fu l. On s ta n d in g , th e p a tie n t co u ld b e a r h is b o d y w e ig h t w ith o u t to o m u ch d is co m fo rt . Th e p h ys icia n o rd e re d a n a n te ro p o s te rio r a n d a la teral radiograph of the ankle region, both of which showed nothing abnormal. This patient was d iagno sed a s having an acute sprain of t he lateral ankle. 55. Which li gament is most likely to ha ve been dama ged? A. The de ltoid ligamen t B. The ant erior talofibul ar ligament C. The plant ar cal caneon avicul ar l igament D. The anterior ligament of the inf erior ti biofibul ar joint E. The post erior talofibul ar ligament A 29-year-old woman was involved in an autom obil e a cciden t. Her car ski dde d into a tree , and she was thrown forward, striking her right knee on the dashboard. At examination in the emergency departme nt, she wa s found to have a pos terior fracture dislocation of her right hip joint. 56. What bone or bones are lik ely to have been fractur ed? A. The gr eater tuber osity of the femur B. The floor of the acet abul um C. The post erior rim of the acet abulum and f ract ure of the femoral hea d D. The lesser trochanter of the femur E. The anter ior inferior iliac spi ne 57. What ana tomic st ructure is likely to be com promised in a h ip dislocation of this ty pe? A. The t endon of obt urator internus


B. C. D. E.

The s ciatic ner ve The quadr atus femor is mus cle The g luteus max imus mus cle The s uper ior gluteal ner ve

ANSWERS TO REVIEW QUESTIONS 1. 2. 3. 4. 5. 16.

27.

6. B 11. C 7. A 12. C 8. B 13. F 9. E 14. C 10. A 15. D With the kn ee j oint ex tended, the hams tring mu scles are stretched a nd limit t he d egree of f lexion o f the h ip joint. D 20. B 23. B A 21. D 24. B E 22. A 25. D A. Remember th at th e skin of the back bel ow th e level of the iliac crests drains into the horizontal group of superf icial inguinal ly mph nod es E 28. E 29. A

30. 31.

B D.

17. 18. 19. 26.

C E B D D F.

32. 35.

B A.

36. 37.

C D.

Rememb er that th e muc ous membr ane o f th e lower half of the anal canal has the same lymp ha tic d ra ina ge as th e skin ar ou nd th e a nu s— namely, into the medial group of horizontal supe rficia l inguin al n od es. 33. C 34. E The nut rient a rtery, which is a branch of the obturator art ery, reache s the femoral head in children along the li gament of t he h ead a nd e nters the b one at the fovea capitis. The femoral head is separated from the arteries supplying the neck of the femur by the ep iph yseal c artilage .

38.

D.

39. 40. 45.

C D E.

46. 47. 48. 49. 50. 51.

vertors of the foot are m ainly s upp lied by the tibial nerve. T he skin on the m edial side of the leg is s upplie d by the sap he no us ne rve, which is a bra nc h of the femoral nerve. A. The s hort head of the biceps femori s muscl e is suppli ed b y the c ommon peroneal nerve. B. The g luteus medi us m uscle is a strong a bduct or of the h ip joint. D. The neck o f the femor al h ernia is related im medi ately laterally to the femoral vein. C. The s oleus does not ari se fro m the f emor al condyles. D. The s arto rius mus cle is a n abduct or of th e hi p joint. E. The inf erio r glutea l ar te ry emer ges from t he greater sciati c foramen .

52.

E.

53.

B.

54. 55.

C B.

56.

C.

57.

B.

The right gluteus medius and the right gluteus minimus tilt the pelvis so that the left lower limb is raised, thus permitti ng the left f oot to b e ad vanced forward clear of the ground .

The s oleus and t he g astrocnemi us mus cle s are at tached to the calcaneum via the tendo calcaneus. These muscles plantar flex the ankle joint. The plantaris is only a weak plantar flexor muscle. 41. C 43. B 42. C 44. C The pl antar flexors of the ankl e joint and the in-

The great sapheno us vein ha s numer ous communications with the deep veins of the leg through the valved perforating veins. The obt urator ne rve ent ers the th igh thr oug h the obturator canal. The anter io r talofibu la r liga ment i s very common ly dam aged, more so than those lig ame nts on the medial side of the joint. Excessive inversion of the foot with plantar flexion of the ankle or attempted medial rotation of the ankle is the common cause. The head of the femur is driven back ward by t he force of the accident through the posterior rim of the acetabulum that is fractured. The head of the femu r may also be fractured. The s ciatic ner ve is commonl y damag ed i n this type of fracture dislocation.

Snell Lower Limb

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