Author: Tatum Khouri, MD
Senior Editor: Kristine Karlson, MD, FAMSSM
Editor: Caitlin Lewis, MD

Patient Presentation:
A 33 year old woman presented to her primary care physician with concern of right ankle weakness.

History:
She reported history of multiple prior ankle injuries, most notably an inversion injury 2 years prior. X-rays obtained at an urgent care were reportedly negative for fracture at that time. She recalled after this injury, she developed subsequent progressive difficulty with plantarflexion and loss of ability to dorsiflex. She noticed atrophy of her right lateral calf and foot muscles as well as decreased sensation in her toes.. . She noted she tended to sit in a crossed leg position. She learned to adjust her gait by picking up her right leg to compensate for foot drop. She has continued running 3-4 days per week, each 2-3 miles. Her primary care physician ordered an MRI of the ankle and referred her to sports medicine. At her sports medicine consultation, she was referred to physical therapy and an electromyogram was ordered. At initial follow-up, she had made no improvements after 5 physical therapy visits despite good compliance with her home exercise program.

Physical Exam:
Overt atrophy of the gastrocnemius and anterior tibialis was noted in comparison to the left. She had intact arches without hindfoot pronation. Active ROM was observed to be decreased in dorsiflexion, plantarflexion, eversion and inversion Movement in all directions were pain-free. There was 3/5 strength with inversion, eversion, and dorsiflexion. There was mild tenderness to palpation at the anterior talofibular ligament and calcaneofibular ligament. Otherwise, she was nontender throughout the ankle and foot. She had a negative anterior drawer test, negative talar tilt at 0 and 30 degrees, negative dorsiflexion external rotation test, negative Thompson test. She reported decreased sensation in both the superficial and deep peroneal nerve distribution. She had 1+ hamstring reflexes bilaterally, 2+ patellar and Achilles reflexes bilaterally. She was unable to perform right-sided toe raises. Her body mass index was 27.

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