CASE
A 12-year-old male presented with right knee pain that began after he fell during football practice about 18 months before. Shortly after the injury, the patient noted mild swelling and feelings of minor instability. The pain, which became localized over his anterior knee, seemed to wax and wane. The patient rated the pain at its most severe as 7 on a 10-point scale. One month after the injury, a pediatrician diagnosed knee strain. The patient played football for the entire season, but because the injury was not getting better over time, he was referred to pediatric orthopedics for further evaluation.
Medical history was significant only for seasonal allergies, and except for occasional ibuprofen for sports-related pain, the patient was taking no medication. His gait was normal and symmetric. No swelling, effusion, or ecchymosis was noted in the right knee. Range of motion in the hips, knees, and ankles was full and painless bilaterally. The anterior region of the right knee was mildly tender, but there was no pain to palpation over the joint line. The knee was stable to varus and valgus stress at 0° and 30°. Lachman test was negative with a solid end point. Results of a McMurray test, patellar grind test, and dial test were also negative. Pedal pulses were 2+ bilaterally; capillary refill time was less than 2 seconds; and sensation was intact distally. Strength was equal in both legs, and hamstring tightness was noted with a popliteal angle of 45°. A radiograph of the right knee was obtained (Figure 1).
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