Author: Crystal Graff, MD
Co Author #1: Lindsay Burke, MD
Co Author #2: Adele Meron, MD
Senior Editor: Heather Rainey, MD
Editor: Reno Ravindran, MD

Patient Presentation:
A 60-year-old male with history of right ankle fracture status post fixation in 2008 and essential tremor presented with right foot pain and muscle spasms while biking. He reports a two-year history of spontaneous involuntary ankle supination occurring about five miles into his typical twenty mile per day bike ride that has become more frequent and bothersome over time. He notes associated discomfort due to malpositioning of the foot inside his biking shoes (feeling like shoes are going to clip out of pedals), as well as cramping pain which radiates proximally into his calf and posterior knee. Toe curling of the affected foot typically precedes these events. He made mechanical alterations to his bike and used an ankle brace without relief of symptoms. He denies weakness, paresthesias, or history of low back pain.

History:
Past medical history of essential tremor, anxiety, and hypothyroidism. Past surgical history of ankle fracture status post fixation surgery in 2008 (with hardware still in place). Family history of Parkinson's disease in grandmother, great aunt, and great grandfather.

Physical Exam:
Physical exam was significant for tenderness to palpation over the right anterolateral tibiotalar joint near previous hardware placement. Strength was full throughout bilateral lower extremities. Sensation was intact. He had notable large amplitude right upper extremity resting tremor, mild right lower extremity resting tremor, asymmetric bradykinesia and rigidity. Achilles and patellar reflexes were 2+ bilaterally; he had no clonus and a downgoing Babinksi. He had asymmetric rigidity of the right upper extremity. His posture was stooped and gait was non-antalgic with short stride length. His speech displayed moderate hypophonia.

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