Author: Matthew Brennan, MD
Co Author #1: Matthew J. Brennan, MD
Co Author #2: Garry W. K. Ho, MD
Senior Editor: Jessalynn Adam, MD
Editor: Siobhan Statuta, MD, FAMSSM

Patient Presentation:
A 17 year old overweight male high school football player (linebacker) was initially evaluated for a limp on the sidelines of a football game.

History:
The athlete first noticed a sharp pain along the medial aspect of his left thigh during practice six days prior. The pain initially improved without intervention, but then worsened and extended distally to the mid-calf and, eventually, to the ankle; the pain remained only on the medial aspect of his leg. He also reported a limp and the inability to fully extend his left knee. There was no known injury. The athlete denied bruising, redness, or swelling. He never had similar pain previously. There was no back pain or left groin pain. He denied recent fevers or illness. Due to the limited diagnostic capabilities on the field of play, the patient was seen in the clinic the day following the initial sideline evaluation.

Physical Exam:
General: Well-appearing male with BMI of 28.2 (94th percentile). Cardiovascular: 2+ DP and PT pulses bilaterally. Neurologic: Antalgic gait. 5/5 strength of hips, knees, ankles. Sensation intact. Musculoskeletal: No swelling, ecchymosis, erythema, or deformity of left lower extremity. Tenderness to palpation along medial aspect of left lower extremity extending from mid-thigh to slightly superior to medial malleolus. Active range of motion of the left knee 30 to 145 degrees; guarding during passive extension beyond 30 degrees. Left knee Lachman, anterior drawer, posterior drawer, and McMurrays limited due to guarding; other provocative maneuvers normal of the left hip, knee, and ankle.

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