Author: Ashlee LaFontaine, MD
Co Author #1: Dave Soma, M.D.
Co Author #2: Peter Gloviczki, M.D.

Patient Presentation:
Patient is a 17-year-old male athlete who presented with chief complaints of left foot coolness, numbness, and discomfort with activity.

History:
Several months before presentation, the patient first noticed numbness and coolness of his left foot predominantly while running. He plays several sports with a large amount of running, including basketball, cross-country running, and track. Symptoms would begin early in exercise, become persistent, and gradually fade without any specific intervention. Occasionally, symptoms occurred with cold exposure. The area of numbness was localized over the medial forefoot primarily involving his first, second, and third toes, extending proximally almost to the calcaneal region. During these episodes, he would occasionally experience cramping and discomfort extending to the lower posterior calf. Other complaints included a yellow-white discoloration of the skin associated with his symptoms. The patient’s symptoms occurred with moderate intensity activity and resolved with rest. His sports performance and daily activities were overall unaffected, however he would often have difficulty falling asleep due to aches in his leg at night. He denied pain, previous occurrences, trauma, tobacco use, symptoms in the right leg, gait changes, or weakness during or after activity. Of interest, his father is a former smoker and recently diagnosed with symptomatic anomalous origin of the right coronary artery from the left sinus of Valsalva.

Physical Exam:
Musculoskeletal: Normal muscle bulk, tone, strength, ROM, and reflexes. No obvious gait or structural abnormalities. No tenderness to palpation. Sensation intact to light touch. No joint instability. Normal toe and heel walking. Legs warm to touch with left foot slightly cooler than the right. Right dorsalis pedis (DP) and posterior tibial (PT) pulses were 2+. Left DP and PT pulses were absent. Popliteal pulses were difficult to palpate but seemed asymmetric greater on the right than left. Otherwise, normal.

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