Lower limb nerve injury

Question 1

Where would a patient have muscle wasting or motor loss with femoral nerve damage?

Answer 1

Anterior thigh compartment

Iliacus (can’t see)

Question 2

What functional issues would be present with femoral nerve damage?

Answer 2

Weak or absent knee extension
Weak hip flexion (psoas muscle spared as L1-L3 innervated)
Weak or absent patella ligament reflex
Patient may have difficulty rising from seated position and may appear to push thigh back with hand when walking

Question 3

How can the femoral nerve be injured?

Answer 3

Can be compressed on the Iliacus during childbirth

Femoral triangle damage (e.g. penetrating injury or iatrogenic)

Question 4

What sensory loss would a patient experience with femoral nerve damage?

Answer 4

Anterior thigh
Antero-medial leg
Postero-medial leg

Question 5

What gait would a patient with inferior gluteal nerve damage display?

Answer 5

Gluteus maximus (lurching) gait - trunk lurches on heel strike of affected limb to prevent it toppling forward

Question 6

What gait would a patient with superior gluteal nerve damage display?

Answer 6

Trendelenburg gait (or Trendelenburg sign when standing on one leg) - pelvis tilts towards unsupported side during gait

Question 7

How can the sciatic nerve be damaged?

Answer 7

Posterior dislocation of hip
Piriformis entrapment
Penetrating injury in gluteal region (incl. poorly placed intramuscular injection)

Question 8

How can the obturator nerve be damaged?

Answer 8

Pelvic brim during childbirth
Pelvic cavity during surgery
Fascial entrapment
Compression (ovulation, ovarian cysts, ovarian tumours)

Question 9

What functional issues would a patient experience with obturator nerve damage?

Answer 9

Instability or weakness during gait 
Circumducting/ wide-base gait 
External rotation and abduction when walking 
Lack of propulsion during running 
Groin pain if compressed

Question 10

What is Hilton’s law?

Answer 10

A mobile joint is innervated by the nerve innervating the muscle acting on the joint and also the nerve innervating the skin over the joint - pain referral mechanism

Question 11

What functional issues would a patient experience with sciatic nerve damage?

Answer 11

Weak knee flexion
Absent ankle and digit dorsiflexion/ plantarflexion
Foot deformity/ collapse

Question 12

What sensory loss would a patient experience with sciatic nerve damage?

Answer 12

Lateral leg, heel and majority of dorsal aspect of foot

Question 13

How can the common fibular nerve be damaged?

Answer 13

Sciatic nerve injury (will result in loss of common fib)
Popliteal fossa region (penetrating injury)
Lateral aspect of fibula head and neck (trauma e.g. car bumper)

Question 14

What functional issues would a patient experience with common fibular nerve damage?

Answer 14

Weak dorsiflexion (resulting in foot slap when walking) or absent dorsiflexion (resulting in foot drop) 
Absent eversion (may increase risk of inversion injuries)

Question 15

What sensory loss would a patient experience with common fibular nerve damage?

Answer 15

Antero-lateral leg and postero-lateral leg (proximal region)

Question 16

How can the tibial nerve be damaged?

Answer 16

Posterior hip dislocation or gluteal region (sciatic)
Popliteal fossa
Tarsal Tunnel (deficits isolated to foot)

Question 17

What functional issues would a patient experience with tibial nerve damage?

Answer 17

Weak or absent plantarflexion (if injury was proximal)
Slow walking and short strides
Minimal arch support (so flat foot or deformity)

Question 18

What sensory loss would a patient experience with tibial nerve damage?

Answer 18

Distal, posterior leg and heel of foot