LOWER LIMB ANATOMY

Question 1

A 37-year-old woman had been suffering for months from piriformis entrapment syndrome, which was not relieved by physical therapy. Part of the sciatic nerve passed through the piriformis, and a decision was made for surgical resection of the muscle. When the area of entrapment was identified and cleared, a tendon could be seen emerging through the lesser sciatic foramen, at first hidden by two smaller muscles and several nerves and vessels destined for the region of the perineum. The tendons of which of the following muscles pass through this opening?

A-Obturator internus
B-Obturator externus
C-Quadratus femoris
D-Gluteus minimus and medius

Answer 1

ANSWER: A-Obturator internus

*The tendon of the obturator internus leaves the pelvic cavity by passing through the lesser sciatic foramen, wrapping around the lesser sciatic notch, changing direction by about 90 degrees. It is joined there by the superior and inferior gemelli and inserts with them on the upper portion of the greater trochanter.
•The obturator externus arises on the external surface of the pubic bone and obturator membrane and inserts on the greater trochanter.
*The quadratus femoris arises from the ischial tuberosity and inserts on the intertrochanteric line of the femur.
•The gluteus medius and minimus insert together on the lateral aspect of the greater trochanter.

Question 2

A 67-year-old woman has been suffering from osteoporosis for the past year. During her annual checkup, radiologic examination reveals an angle of 160 degrees made by the axis of the femoral neck to the axis of the femoral shaft. Which of the following conditions is associated with these examination findings?
A. Coxa vara
B. Coxa valga
C. Genu valgum
D. Genu varum
E. Hallux valgus

Answer 2

ANSWER: B-COXA VALGA
•Generally, the angle of inclination between the neck and shaft of the femur in older age decreases to around 120 degrees.
•However, in pathologic conditions it can either increase or decrease from the predicted value.
•When the angle of inclination increases, it is referred to as coxa valga.
•Coxa vara on the other hand is a condition characterized by a decreased angle of inclination.
•Genu varum and genu valgum are deformities characterized by a decreased Q-angle and increased Q-angle, respectively.
•The Q-angle refers to the angle between the femur and tibia.
•Hallux valgus is a condition that presents with a lateral deviation of the large toe.

Question 3

A 34-year-old male runner visits the outpatient clinic complaining of pain in his foot for the past week. Physical examination reveals inflammation of the tough band of tissue stretching from the calcaneus to the ball of the foot. Which of the following conditions is characteristic of these symptoms?
A. Pott’s fracture
B. Dupuytren fracture
C. Tarsal tunnel
D. Plantar fasciitis
E. Rupture of spring ligament

Answer 3

ANSWER: D-PLANTAR FASCIITIS
•Plantar fasciitis is a common clinical condition that results from tearing or inflammation of the tough band of tissue stretching from the calcaneus to the ball of the foot (the plantar aponeurosis).
•It usually happens to people who are on their feet frequently or engaged in athletics, especially running and jumping.
•Plantar fasciitis is usually most painful in the morning, just after getting up from bed and beginning to walk.
•Rest, orthotics, night splints, and antiinflammatory medications are employed in treatment.
•A Pott’s fracture is a bimalleolar fracture, specifically a fracture of the distal end of the fibula (lateral malleolus) and medial malleolus, with outward displacement of the foot.
•Dupuytren’s fracture involves fracture of the distal fibula with dislocation of the foot. Each of these fractures occurs due to sudden and forceful eversion of the foot.

Question 4

A 50-year-old man is admitted to the emergency department after a car crash. An MRI examination reveals an injured anterior cruciate ligament. Physical examination reveals a positive drawer sign. Which of the following signs is expected to be present during physical examination?
A. The tibia can be slightly displaced anteriorly
B. The tibia can be slightly displaced posteriorly
C. The fibula can be slightly displaced posteriorly
D. The fibula can be slightly displaced anteriorly
E. The tibia and fibula can be slightly displaced anteriorly

Answer 4

ANSWER: A-The tibia can be slightly displaced anteriorly

When the anterior cruciate ligament is torn, the tibia can be slightly displaced anteriorly from the area of the knee joint by pulling firmly with both hands upon the leg, with the patient in a seated position. This is a positive anterior drawer sign.

Question 5

A 23-year-old male basketball player injured his foot during training and is admitted to the emergency department. An MRI examination reveals a hematoma around the medial malleolus. Upon physical examination the patient shows excessive eversion of his foot. Which of the following ligaments most likely has a tear?
A. Plantar calcaneonavicular (spring)
B. Calcaneofibular
C. Long plantar
D. Short plantar
E. Deltoid

Answer 5

ANSWER: E. Deltoid
•One important function of the deltoid ligament is the prevention of excessive extension of the ankle.
•The ligament is so strong that excessive eversion can cause the medial malleolus to be pulled off (an avulsion fracture) rather than tearing the deltoid ligament.

Question 6

A 5-year-old boy is admitted to the emergency department after a car collision. Radiologic examination reveals a fracture of the head of the femur. An MRI examination reveals a large hematoma. Which of the following arteries is most likely injured?
A. Deep circumflex iliac
B. Acetabular branch of obturator
C. Descending branch of lateral circumflex femoral
D. Medial circumflex femoral
E. Radicular branches of circumflex artery

Answer 6

ANSWER: B. Acetabular branch of obturator
•In infants and children up to about 8 years of age, the head of the femur gets its arterial supply by a direct branch of the obturator artery (variably, the medial circumflex femoral).
•The arterial supply reaches the head of the femur at the fovea capitis by traveling along the ligament of the head of the femur.
•Probably due to repeated torsion on the ligament, and therefore on the artery, this artery occludes early in life.
•In turn, this source of supply is replaced by branches of the gluteal and femoral circumflex vessels.

Question 7

A 72-year-old woman is admitted to the emergency department after an episode of stroke. During neurologic examination the patient shows no response to the ankle reflex test. Which of the following nerve roots is responsible for this reflex?
A. L2
B. L3
C. L4
D. L5
E. S1

Answer 7

ANSWER: E.S1

•The ankle jerk reflex involves S1 and S2 levels.
•L2 to L4 are involved in the patellar reflex. L5 is not a component of a deep tendon reflex.

Question 8

A 20-year-old man visits the family physician complaining of difficulty to flex and medially rotate his thigh while running and climbing. Which of the following muscles is most likely damaged in this individual?
A. Rectus femoris
B. Tensor fasciae latae
C. Vastus intermedius
D. Semimembranosus
E. Sartorius

Answer 8

ANSWER: B. Tensor fasciae latae

•The tensor fasciae latae assists in flexion of the thigh, as well as medial rotation and abduction.
•Damage to this muscle would adversely affect these motions.
•The rectus femoris extends the hip.
•The vastus intermedius extends the knee.
•The semimembranosus extends the hip and flexes and medially rotates the knee.
•The sartorius assists in flexion and lateral rotation of the hip, as well as in medial rotation of the knee.

Question 9

A 49-year-old man is admitted to the emergency department with a cold and pale foot. Physical examination reveals that the patient suffers from peripheral vascular disease; his popliteal artery is occluded and no pulse is felt upon palpation. What is the landmark to feel the pulse of the femoral artery?
A. Adductor canal
B. Femoral triangle
C. Popliteal fossa
D. Inguinal canal
E. Pubic symphysis

Answer 9

ANSWER: B. Femoral triangle

•The femoral triangle is the best place to palpate the femoral pulse.
•It is bounded by the sartorius muscle laterally, adductor longus medially, and the inguinal ligament superiorly.
•It contains the femoral vein, artery, and nerve (from medial to lateral, respectively).
•The adductor canal lies deep between the anterior and medial compartments of the thigh and therefore cannot be palpated.
•The popliteal fossa is the fossa at the back of the knee and contains the popliteal artery and vein, tibial nerve, and common fibular (peroneal) nerve.
•The femoral pulse cannot be palpated here.
•The inguinal canal is in the pelvis and is in communication with the anterior abdominal wall.
•It contains the spermatic cord in males and round ligament of the uterus in females.

Question 10

A 49-year-old man is admitted to the emergency department complaining that he has difficulties walking. Physical examination reveals that the patient suffers from peripheral vascular disease. An ultrasound examination reveals an occlusion of his femoral artery at the proximal portion of the adductor canal. Which of the following arteries will most likely provide collateral circulation to the thigh?
A. Descending branch of the lateral circumflex femoral
B. Descending genicular
C. Medial circumflex femoral
D. First perforating branch of deep femoral

Answer 10

ANSWER: A. Descending branch of the lateral circumflex femoral

•If the femoral artery is occluded, the descending branch of the lateral circumflex femoral will provide collateral circulation to the thigh.
•The descending genicular artery is a branch of the femoral and therefore would also be occluded.
•The medial circumflex femoral artery is a proximal branch of the deep femoral artery and supplies part of the head of the femur.
•The first perforating branch of the deep femoral artery supplies a small portion of the muscles of the posterior thigh.
•Finally, the obturator artery supplies a very small artery and vascularizes only the most proximal part of the head of the femur and usually only during the early years of life.

Question 11

A 34-year-old man is lifting heavy weights while doing squats. Unfortunately, while making a maximal effort, he drops the weight and immediately grabs at his upper thigh, writhing in pain. The man is admitted to the emergency department and during physical examination is diagnosed with a femoral hernia. What reference structure would be found immediately lateral to the herniated structures?
A. Femoral vein
B. Femoral artery
C. Pectineus muscle
D. Femoral nerve

Answer 11

ANSWER: A. Femoral vein

•In a femoral hernia, abdominal contents are forced through the femoral ring, which is just lateral to the lacunar ligament (of Gimbernat) and just medial to the femoral vein.
•The femoral vein would be found immediately lateral to the femoral hernia.
•This is correct in most cases because in the majority of people, the femoral vein is found more medial to both the femoral artery and nerve in the femoral triangle.
•The adductor longus muscle as well as the pectineus muscle would be found deep and medial to the hernia.

Question 12

A 25-year-old man, an intravenous drug abuser, had been injecting himself with temazepam (a powerful intermediate acting drug in the same group as diazepam (Valium) and heroin for 5 years, leaving much residual scar tissue over points of vascular access. The patient is admitted to the emergency department for a detoxification program requiring an intravenous infusion. The femoral veins in his groin are the only accessible and patent veins for intravenous use. Which of the following landmarks is the most reliable to identify the femoral veins?
A. The femoral vein lies medial to the femoral artery.
B. The femoral vein lies within the femoral canal.
C-The femoral vein lies lateral to the femoral nerve
D-Femoral vein is in the lateral component of femoral sheath

Answer 12

ANSWER: A. The femoral vein lies medial to the femoral artery.

•The femoral vein lies medial to the femoral artery in the femoral sheath.
•The femoral sheath is broken into three compartments: lateral, intermediate, and medial.
•The lateral compartment contains the femoral nerve.
•The medial compartment encloses the femoral canal and consists of lymphatic tissue and a lymph node, plus areolar tissue.
•The intermediate contains the femoral vein.

Question 13

A 42-year-old man is bitten on his posterior thigh by a dog. The superficial wound is sutured in the emergency department. Four days later the patient returns to the hospital with high fever and swollen lymph nodes. Which group of nodes first receives lymph from the infected wound?
A. External iliac
B. Vertical group of superficial inguinal
C. Deep inguinal
D. Horizontal group of superficial inguinal
E. Internal iliac

Answer 13

ANSWER: B. Vertical group of superficial inguinal

•The superficial inguinal nodes are located near the saphenofemoral junction and drain the superior thigh region.
•The vertical group receives lymph from the superficial thigh, and the horizontal group receives lymph from the gluteal regions and the anterolateral abdominal wall.
•The deep inguinal lie deep to the fascia lata and receive lymph from deep lymph vessels (popliteal nodes).
•The external and internal iliac nodes first receive lymph from pelvic and perineal structures

Question 14

During a battle, a 19-year-old soldier is shot in the lateral aspect of the right foot by a bullet that ricocheted off a building. The soldier is taken to a field hospital. A radiograph of the foot reveals that the base of the fifth metatarsal was completely obliterated. Which of the following muscles is most likely affected by this injury?
A. Tibialis anterior
B. Fibularis (peroneus) longus
C. Gastrocnemius
D. Fibularis (peroneus) brevis
E. Extensor hallucis longus

Answer 14

ANSWER: D. Fibularis (peroneus) brevis

•The fibularis (peroneal) brevis muscle originates from the lateral lower two thirds of the shaft of the fibula and inserts on the tubercle at the base of the fifth metatarsal.
•Any injury to this area will affect this muscle.
•Patients will present with a weakness in the eversion of the foot.
•Fibularis (peroneus) longus, extensor hallucis longus and tibialis anterior all insert on the medial side of the foot and will not be affected in this patient.
•The gastrocnemius inserts via the Achilles tendon to the posterior surface of the calcaneus.

Question 15

A 29-year-old woman is involved in a car crash and is taken to the emergency department. Radiographs reveal a fracture of her pelvis. During healing of the pelvic fracture, a nerve becomes entrapped in the bone callus. Musculoskeletal examination reveals an inability to adduct the thigh. Which of the following nerves is most likely affected?
A. Obturator
B. Femoral
C. Inferior gluteal
D. Superior gluteal
E. Tibial

Answer 15

ANSWER: A. Obturator

•The obturator nerve is a branch of the lumbar plexus that originates from L2 to L4.
•It descends medial to the psoas on the posterior abdominal wall into the pelvis where it runs along the lateral wall of the lesser pelvis, above and anterior to the obturator vessels.
•It enters into the medial thigh via the obturator canal (an opening above the obturator membrane) to supply the obturator externus muscle and the adductors of the thigh.
•The femoral nerve innervates the anterior compartment of the thigh.
•The inferior gluteal innervates the gluteus maximus muscle, while the superior gluteal innervates the gluteus minimus and medius.
•The tibial nerve innervates the posterior compartment of the lower limb.

Question 16

A 29-year-old man is brought to the physician for removal of a cast from his left leg. He had sustained a fracture of the left lower extremity 6 weeks prior which was immobilized in a cast that extended from just below the knee to the foot. At the time of injury, there was severe pain but normal strength in the extremity. When the cast was removed, physical examination showed a pronounced left foot drop with paresthesia and sensory loss over the dorsum of the left foot and lateral leg. Injury to which nerve is the most likely cause?
A. Common fibular (peroneal)
B. Superficial fibular (peroneal)
C. Deep fibular (peroneal)
D-Sciatic nerve

Answer 16

ANSWER: A. Common fibular (peroneal)

•The common fibular (peroneal) nerve is a branch of the sciatic nerve.
•It descends on the lateral side of the popliteal fossa before winding around the head of the fibula. It then divides into superficial and deep nerves that supply the lateral and anterior compartments of the leg respectively.
•Due to its superficial course, it is easily injured in patients with long leg casts (which run from just below the knee).
•The nerve supplies the dorsiflexors of the leg, the skin of the first web space (via the deep fibular), the evertors of the foot, and the skin of the lateral side of the leg and dorsum of the foot (via the superficial fibular).

Question 17

A 12-year-old boy is brought to the physician by his father because of redness and swelling of his left foot for 24 hours. Three days earlier he had scraped his foot while wading in a drainage ditch. Examination of the foot shows a purulent abrasion with edema, erythema, and tenderness on the lateral side. Infection will most likely spread from the lateral side of the foot to the regional lymph nodes in which area?
A. Lateral surface of the thigh
B. Medial malleolus, posteriorly
C. Popliteal fossa
D. Sole of the foot

Answer 17

ANSWER: C. Popliteal fossa

•The lymphatic drainage of the foot follows its venous drainage.
•The small saphenous vein drains the lateral side of the foot and the posterolateral leg.
•It drains into the popliteal vein in the popliteal fossa.
•Therefore a lesion on the lateral side of the foot will drain to the popliteal nodes in the popliteal fossa.

Question 18

A 22-year-old soccer player collides with one of her teammates. During examination on the field, the posterior drawer test was performed and the tibia moved backward in relation to her femur. Injury to which structure is confirmed by performing this test?
A. Anterior cruciate ligament
B. Lateral collateral ligament
C. Medial collateral ligament
D. Medial meniscus
E. Posterior cruciate ligament

Answer 18

ANSWER: E. Posterior cruciate ligament

•The posterior cruciate ligament runs from the posterior aspect of the intercondylar area of the tibia to the medial wall of the intercondylar fossa.
•It prevents posterior displacement of the tibia relative to the femur.
•This is usually tested with the posterior drawer test, in which the physician pushes the tibia backward while the knee is flexed in an attempt to displace it posteriorly.
•This is called the positive posterior drawer sign.
•The anterior cruciate ligament prevents anterior displacement of the tibia on the femur.
•The medial and lateral collateral ligaments stabilize the medial and lateral sides of the knee joint, respectively.
•The medial meniscus is an intracapsular fibrocartilage that improves the articulation of the femur and tibia.

Question 19

A 16-year-old boy presents to the emergency department with a fracture of the first and second toes of his right foot. He received an anesthetic injection in the first web space of his foot, to permit easy manipulation and correction. Which nerve was blocked by the anesthesia?
A. Saphenous
B. Cutaneous branch of deep fibular (peroneal)
C. Cutaneous branch of superficial fibular (peroneal)
D. Sural
E. Common fibular (peroneal)

Answer 19

ANSWER: B. Cutaneous branch of deep fibular (peroneal)

•The deep fibular (peroneal) nerve is a branch of the common fibular (peroneal) nerve.
•It is mainly a motor nerve that innervates the anterior compartment of the leg. Its only cutaneous innervation is to the skin of the first web space.
•The saphenous nerve innervates the medial side of the leg and foot.
•The cutaneous branch of superficial fibular (peroneal) nerve innervates the anterior part of the lower leg and the dorsum of the foot.
•The sural nerve innervates the lateral side of the leg and foot.

Question 20

During an interview, a 30-year-old man who is a psychiatric patient suddenly becomes aggressive. In order to calm him down, the patient is given an intramuscular injection in the upper lateral quadrant of the buttock. The injection is given at this specific location to prevent damage to which of the following nerves?
A. Lateral femoral cutaneous
B. Sciatic
C. Superior gluteal
D. Obturator
E. Inferior gluteal

Answer 20

ANSWER: B. Sciatic

The gluteal region can be divided into quad-rants by two lines positioned using palpable bony landmarks.
One line runs inferiorly from the highest point of the iliac crest.
The second line runs horizon-tally midway between the iliac crests and the ischial tuberosity.
This divides the gluteal region into four quadrants.
The sciatic nerve runs through the lower medial quadrant and must be avoided during intragluteal injections.

Question 21

A lateral blow to the knee during a tackle in a football game injures a 24-year-old woman. Field examination reveals an “anterior drawer sign.” An MRI demonstrates injury to several structures of the knee, including her medial meniscus. Which structure might also have been injured by the tackle?
A. Medial collateral ligament
B. Lateral collateral ligament
C. Lateral meniscus
D. Posterior cruciate ligament
E. Tendon of the semitendinosus

Answer 21

ANSWER: A. Medial collateral ligament

•A lateral blow to the knee often produces a trio of injuries referred to as the “unhappy triad.”
•This involves damage to the anterior cruciate ligament, medial meniscus, and medial collateral ligament.
•The medial meniscus and medial collateral ligament are often damaged together, as they are tightly attached to each other.
•The lateral collateral ligament and lateral meniscus would not be damaged because a blow to the lateral knee would not put strain on these structures.
•Damage to the posterior cruciate ligament would produce a positive “posterior drawer sign” and is typically damaged during a blow to the medial side of the knee.
•The posterior cruciate ligament is stronger than the anterior and is only typically damaged when a person falls on the tibial tuberosity of a flexed knee.
•Tendon of semitendinosus is on the medial side of the knee but is not attached closely to the other structures or taut in this injury type.

Question 22

A 58-year-old woman presents to the outpatient surgery clinic for removal of varicose veins on the medial aspect of her foot. The operation was successful however, one month later she reports loss of sensation over the medial aspect of her leg and foot. Which of the following nerves was most likely injured during the procedure?
A. Saphenous
B. Obturator
C. Lateral femoral cutaneous
D. Tibial
E. Femoral

Answer 22

ANSWER: D. Tibial

•The saphenous nerve runs with the great saphenous nerve which was being removed from patient.
•Sensory innervation to the areas of loss described is by the L4 root, which is carried by the saphenous nerve.
•The obturator nerve innervates the skin on the superior medial thigh. Lateral femoral cutaneous innervates the lateral aspect of the thigh.
•The tibial nerve supplies cutaneous innervation to the lateral aspect of the leg and if damaged would also produce muscular dysfunction.
• The femoral nerve is a motor and sensory nerve and is the origin of the saphenous nerve.

Question 23

A 16-year-old teenage girl suffered an inversion sprain of her ankle during dance class. Physical examination in the clinic most likely reveals severe tenderness over which ligament?
A. Calcaneonavicular (spring)
B. Calcaneofibular
C. Long plantar
D. Short plantar
E. Deltoid

Answer 23

ANSWER: B. Calcaneofibular

•Ligaments act to prevent excessive movement of joints.
•When a joint is forced into a position, that ligament is stretched and will be tender or rupture if the force is severe enough.
•Inversion is when the sole of the foot is turned medially and therefore will stretch ligaments that oppose this action.
•The calcaneofibular ligament is on the lateral side and stretches between the fibula and the calcaneous.
•It is the only ligament that would be damaged during such an action.
•The calcaneonavicular and long and short plantar ligaments are located on the plantar surface of the foot and will not be damaged during inversion injuries.
•The deltoid ligament is located medially and will not be affected.

Question 24

A 58-year-old man visited his physician for his annual check-up. Physical examination reveals a hyper reflexive patellar reflex. Which muscle(s) contribute(s) to the tendon that is struck when testing this reflex?
A. Quadriceps femoris
B. Quadratus femoris
C. Sartorius
D. Pectineus
E. Biceps femoris

Answer 24

ANSWER: A. Quadriceps femoris

•The patellar reflex causes extension of the knee and is produced by the quadriceps muscle group which consist of; biceps femoris and vastus lateralis, medialis and intermedius.
•Quadratus femoris is a lateral rotator of the thigh.
•The sartorius is a flexor of the hip and knee, and the pectineus is an adductor and flexor of the hip.

Question 25

A 37-year-old unconscious man is rushed to the emergency department after being retrieved from a motor vehicle crash. On physical examination bruising and obvious deformity is seen over his left knee joint. Radiological studies showed a posteriorly dislocated supracondylar fracture with severe compression of the popliteal artery. Which of the following arteries would ensure adequate blood supply to the leg and foot in this patient?
A. Medial femoral circumflex
B. Lateral femoral circumflex
C. Anterior tibial artery
D. Posterior tibial artery

Answer 25

ANSWER: B. Lateral femoral circumflex

•The lateral femoral circumflex artery is a branch of the femoral artery close to the hip joint.
•It gives a branch that runs down the lateral aspect of the thigh and joins the genicular anastomosis via the superior lateral genicular artery.
•The medial circumflex femoral artery does not provide any branches that descend toward the knee.
•The anterior and posterior tibial arteries are the terminal branches of the popliteal artery and would not receive any blood if the popliteal is damaged.
•The fibular (peroneal) artery is a branch of the posterior tibial artery

Question 26

After a revascularization procedure involving the common iliac artery, a 68-year-old man has difficulty walking. Nerve conduction studies reveal decreased activity in the nerve that innervates the adductors of the thigh. Which nerve is this?
A. Femoral
B. Obturator
C. Common fibular (peroneal)
D. Tibial
E. Sciatic

Answer 26

ANSWER: B. Obturator

•The obturator nerve is responsible for innervation of the thigh adductors which form the medial compartment of the thigh.
•The femoral nerve innervates the anterior compartment and is responsible for extension of the knee.
•Common fibular (peroneal) nerve supplies the anterior and lateral compartments of the leg while the tibial nerve supplies the posterior compartments of the leg and thigh.
•The common fibular (peroneal) and tibial nerves are branches of the sciatic nerve.

Question 27

A 23-year-old woman was taken to the emergency department after being involved in a head-on collision with a truck. On physical examination a hematoma was seen in the medial thigh. A CT scan revealed a fracture of the femur with a ruptured femoral artery. She was taken to the operating room for repair of the damaged structures. Two days postoperatively during physical examination the patient has loss of sensation to the anterior medial thigh and medial side of her leg and foot. Branches of which of the following nerves were most likely injured in the repair of the fracture?
A-Femoral nerve
B-Saphenous nerve
C-Tibial nerve
D-Fibular nerve

Answer 27

ANSWER: A-Femoral nerve
•The skin of the anterior medial thigh and medial leg and foot is supplied by the femoral nerve.
•The saphenous nerve is a branch of the femoral and only supplies the medial leg and foot.
•The obturator supplies the medial and medial posterior aspect of the thigh.
•The tibial nerve supplies the skin of the posterolateral leg, lateral ankle and foot and sole of the foot.
•The fibular (peroneal) nerve supplies the skin over the lateral aspect of the leg and dorsal aspect of the foot

Question 28

A 27-year-old man has had increasing difficulty walking and complained of an area of numbness on the dorsum of his right foot. Examination reveals a hard mass at the anterolateral aspect of his right leg just below the knee. Imaging studies reveal a large bone tumor between the fibula and tibia that is compressing a nerve, accounting for his neurological symptoms. Which of the following is the most likely description of abnormalities on neurological examination?
A. Decreased/absent knee jerk reflex and decreased sensation on the medial aspect of the leg

Answer 28

•The deep fibular (peroneal) nerve is responsible for sensation over the first web space of the foot.
•Dorsiflexion and inversion of the ankle is produced by the muscles supplied by the deep fibular (peroneal) nerve.
•The nerves responsible for the knee jerk reflex, knee flexion, eversion, and plantar flexion are all located superior to the location of the tumor and will not be damaged.
•The nerve located in the space between the tibia and fibula is the deep fibular (peroneal) nerve.

Question 29

A 60-year-old retired male marathon runner complains to his primary care physician that during his daily morning jog he experiences bouts of numbness and tingling on the medial aspect of his heel. Upon further examination the doctor discovers the patient has trouble tiptoeing and shows a positive Tinel’s sign. Which of the following conditions is most characteristic of these symptoms?
A. Plantar fasciitis
B. Ankle inversion sprain
C. Morton’s neuroma
D. Lateral ligament injury
E-Tarsal tunnel syndrome

Answer 29

ANSWER: E-Tarsal tunnel syndrome
•Tarsal tunnel syndrome is a compression neuropathy resulting from the compression of the tibial nerve in the tarsal tunnel.
•The tarsal tunnel is located between the medial malleolus, the inferomedial surface of the calcaneus, and the flexor retinaculum.
•The contents are the tibial nerve and its plantar branches, the tendons of the tibialis posterior, flexor digitorum longus, and the flexor hallucis longus muscles together with the posterior tibial vessels.
•Any inflammation or swelling in the area will compress on these structures, most significantly the tibial nerve.
•The posterior tibial vein will be most easily compressed but the nerve is most clinically significant.
•Clinically, this syndrome is diagnosed with the patient’s history and physical examination findings including a positive Tinel’s sign (lightly tapping over the flexor retinaculum elicits numbness and tingling in the skin over the calcaneus and the sole of the foot).