INJURIES OF THE LOWER EXTREMITY下肢神经损伤（PPT39）课件.ppt

NERVE INJURIES OF THE LOWER EXTREMITY STACY RUDNICKI, MD ASSOCIATE PROFESSOR OF NEUROLOGY Dermatomes of the Leg Root Innervation of the Leg Hip Flexion L 1, 2, 3 Knee Extension L 2, 3, 4 Foot Dorsiflexion L 4,5 Foot Plantar Flexion S1, 2 Knee Flexion L5, S1, S2 Hip Extension L5, S1, S2 Clinical Principles Detecting subtle weakness Get up from squat Quadriceps Stand on tip toes Gastrocnemius/Soleus Stand on heels Tibialis Anterior Reflexes Knee Jerks - evaluates Quadriceps muscle Femoral Nerve Primarily L4 nerve root (also L2, L3) Ankle Jerk - evaluates Gastrocnemius muscle Tibial Nerve Primarily the S1 nerve root (also S2) CASE 1 History 20 yo college student involved in an MVA She suffers multiple pelvic fractures She complains of weakness and numbness of the right leg Exam She has weakness of: Foot dorsiflexion Foot eversion Toe extension Strength is normal in: Foot plantar flexion Foot inversion Toe flexion There is just a hint of weakness in knee flexion SENSORY LOSS Localization Finding Muscle Nerve Root Ft Dorsiflex TIB ANT PER (FIB) L4,5 Grt toe ext EHL PER (FIB) L5 Toe ext EDL, EDB PER (FIB) L4,5 Foot eversion PER L, B PER (FIB) L4,5 Foot plant flex GASTROC, TIB S1,2 SOLEUS Toe flex FDL/FDB TIB L5,S1 Foot inv POST TIB TIB L4,5 Knee flex MULT TIB/PER L5S1S2 Common Fibular (Peroneal) Nerve Common Fib Deep Fib Superficial Fib Per Longus Tib Ant Per Brevis EHL Per Tertius EDB SENSORY LOSS IN A DEEP PERONEAL (FIBULAR) NEUROPATHY Final Diagnosis Sciatic neuropathy with selective involvement of the fibular (peroneal) nerve fibers at the level of the pelvis CASE 2 History The patient is a 45 yo man who complains of burning pain in his right lateral thigh He is otherwise healthy, though over the last 2 years, he has gained 30 pounds because he can’t find time to exercise Exam He has normal strength in all muscles of his leg Reflexes are normal SENSORY LOSS Localization Finding Muscle Nerve Root Sen