Snapshot A 30-year-old woman presents to her primary care physician for left foot pain. The patient reports experiencing a dull ache in the plantar aspect of the left foot. The pain worsens when walking, especially when barefoot or when wearing heels. Her symptoms improve with rest. As the metatarsal heads are squeezed during the physical exam, a "click" is heard between the 3rd and 4th interdigital space. (Morton neuroma) Introduction Nerves of the lower extremity can be entrapped somewhere along its course Lower Extremity Nerve Entrapments Entrapped Nerve Mechanism Presentation Management Femoral Diabetic amyotrophy Injury to the inguinal region intrapelvic structures e.g., gunshot or knife injuries and surgery Pain in the inguinal region hip flexion and external rotation improves pain Dysesthesia of the anterior thigh anteromedial leg Knee buckling and walking difficulty Decreased patellar reflexes Symptomatic management is less severe cases knee brace to improve stability when walking Lateral femoral Entrapment typically occurs in the inguinal ligament Causes include intrapelvic causes pregnancy uterine fibroids abdominal tumors extrapelvic causes trauma to the anterior superior iliac spine mechanical prolonged sitting or standing Also known as "meralgia paresthetica" Paresthesias and pain involving the lateral thigh anterolateral thigh Pain management local anesthetic injection gabapentin NSAIDs Lifestyle modification avoiding prolonged standing Obturator nerve Rare Nerve compression by overlying fascia in the adductor compartment Direct mass effect by tumor Medial thigh pain, especially with activity Sensory loss/paresthesias over the medial thigh Adductor weakness Pain management NSAIDs Lifestyle modification activity modification Saphenous nerve Nerve compression as it courses through the adductor canal Can be compressed more distally (e.g., at the medial leg) Knee pain Infrapatellar pain and numbness Local anesthetic injection Lifestyle modification avoiding activities that aggravate pain Common peroneal Trauma Most common location of injury is around the fibular head Impaired ankle dorsiflexion Dorsal foot numbness Improving mobility and function pain management brace, splint, or orthopedic shoes Superficial peroneal Trauma and nerve compression Stretch nerve injury e.g., repeated ankle sprains Fascial defect Vague pain in the dorsum of the foot Supportive pain management physical therapy braces Posterior tibial Nerve compression distal to the ankle (most common) Also known as "tarsal tunnel syndrome" Vague pain and discomfort in the plantar surface of the foot Supportive pain management Directed at underlying etiology Interdigital neuritis Nerve compression at the level of the transverse intermetatarsal ligament benign neuroma Also known as "Morton neuroma" Burning pain between the 3rd and 4th digits of the foot (most common) Supportive wide shoes and low heels placement of a metatarsal pad pain management