Lower Extremity Neurovascular Relationships

what nerves can become entrapped

lateral femoral cutaneous, saphenous, obturator, sciatic, tibial branch of the sciatic, common fibular branch of the sciatic

path of the subcostal nerve

inferior to rib 12 → anterolateral abdominal wall → ends in space between navel and iliac crest

what area of skin does the subcostal nerve supply

anterolateral abdominal wall

path of the ilioinguinal nerve

between IO and TA → through inguinal canal → ends at skin on proximal medial thigh and external genitalia

what area of skin does the ilioinguinal nerve supply

proximal medial thigh and external genitalia

what area of skin does the iliohypogastric nerve supply

inguinal ligament and proximal thigh

path of genitofemoral nerve

splits into genital and femoral branches at the psoas

what area of skin does the genital branch of the genitofemoral nerve supply

external genitalia

what area of skin does the femoral branch of the genitofemoral nerve supply

femoral triangle (anterior thigh)

path of lateral femoral cutaneous nerve

goes toward ASIS → under inguinal ligament

what area of skin does the lateral femoral cutaneous nerve supply

lateral thigh down to the knee

entrapment site for lateral femoral cutaneous nerve

between the inguinal ligament and ASIS

what is compromised when the lateral femoral nerve is entrapped

cutaneous information of the proximal lateral thigh

path of femoral nerve

spinal nerves come together and innervate the iliopsoas → under the inguinal ligament → explodes into many branches → motor branches go to quad muscles → cutaneous branches supply anterior thigh → continues into saphenous nerve → leaves adductor canal → extends from medial knee to lateral malleolus

what area of skin does the femoral nerve supply

anterior thigh

entrapment site for saphenous nerve

infratellar branch at the medial knee can be cut during arthroscopic surgery

what is compromised when the saphenous nerve becomes entrapped

cutaneous information of the medial leg

path of obturator nerve

medial to psoas → through obturator membrane → splits into many branches (primarily motor) → cutaneous branches travel to skin of medial distal thigh

what area of skin does the obturator nerve supply

distal medial thigh

entrapment site of obturator nerve

can be compromised on the back of the acetabulum during total hip replacement

what is compromised when the obturator nerve becomes entrapped

adductors, gracilis, obturator externus, cutaneous information of the medial distal thigh

what area of skin does the posterior femoral cutaneous nerve supply

posterior thigh

path of the sciatic nerve

emerges below the piriformis → splits into tibial and common fibular branches in the popliteal fossa

entrapment site for sciatic nerve

spasms of scar tissue in the piriformis can cause it to become entrapped

what is compromised when the sciatic nerve becomes entrapped

quadriceps, leg muscles, foot muscles, cutaneous info of the leg and foot

path of the tibial nerve

deep to gastroc and soleus → goes down to the medial malleolus → enters flexor retinaculum (tarsal tunnel) → splits into medial and lateral plantar → medial plantar goes between abductor hallucis and FDL to the medial foot and 3 ½ toes → lateral plantar supplies intrinsic plantar muscles and lateral foot and 1 ½ toes

what is supplied by the medial plantar nerve

some intrinsic foot muscles, cutaneous information of the medial foot and 3 ½ toes

what is supplied by the lateral plantar nerve

most of the intrinsic foot muscles, cutaneous information of the lateral foot and 1 ½ toes

entrapment site for tibial nerve

both branches can be entrapped in the tarsal tunnel

what is compromised when the tibial branch of the sciatic nerve becomes entrapped

foot muscles, muscles of the posterior compartment of the leg, cutaneous information of the foot

path of common fibular nerve

gives off lateral cutaneous sural branches → goes to lateral compartment and proximal fibula → at fibular neck splits into superficial and deep branches → superficial branch travels in lateral compartment and goes to skin in the distal anterior leg and dorsal foot → deep branch travels in anterior compartment and goes to the web space

what is supplied by the superficial fibular nerve

cutaneous information of the anterior leg and dorsum of foot, fibularis longus and brevis

what is supplied by the deep fibular nerve

cutaneous information of the web space, muscles in the anterior compartment of the leg

entrapment sites for common fibular nerve

fractures of the head and neck will affect both branches, compression from an outside force, deep fibular branch can be entrapped by anterior compartment syndrome

what is compromised when the common fibular nerve becomes entrapped

muscles of the anterior and lateral compartments of the leg, cutaneous information of the leg and dorsal foot

what is compromised when the superficial fibular nerve becomes entrapped

lateral compartment muscles and cutaneous information of the anterior leg and dorsal foot

what is compromised when the deep fibular nerve becomes entrapped

anterior compartment muscles and cutaneous information of the web space

path of the sural nerve

created by branches of the tibial and fibular nerves → travels superficial to the gastroc → goes to skin in the lateral distal leg and ankle

path of abdominal aorta

common iliac → external and internal iliac → external turns into femoral → deep branch which gives off medial and lateral femoral circumflex branches → rest of femoral becomes popliteal → splits into anterior and posterior tibial → posterior tibial splits into medial and lateral plantar → lateral plantar becomes plantar arterial arch → anterior tibial becomes dorsal pedis → deep plantar arch

femoral artery in the adductor canal

gives off many muscular branches and when it exits becomes the popliteal artery

path of popliteal artery

runs down back of leg → after popliteus splits into anterior and posterior tibial arteries

path of anterior tibial artery

travels in the anterior compartment with the deep fibular nerve → after the inferior extensor retinaculum it becomes the dorsal pedis → dives into the web space → emerges as the deep plantar artery and closes the plantar arch

path of posterior tibial artery

travels in the posterior compartment → gives off a fibular branch that goes to the lateral malleolus → travels to the medial malleolus → splits into medial and lateral plantar arteries → lateral plantar artery turns into the plantar arterial arch and is closed by the deep plantar artery