Author: Constance Lents, MD
Co Author #1: Ramon Ylanan, MD
Co Author #2: Larry Balle, MD
Senior Editor: Justin Mark Young, MD
Editor: Amy Valasek, MD, MS, FAMSSM

Patient Presentation:
A 13-year-old female track, cross country, and equestrian athlete presented to clinic with right knee pain.

History:
She noted three years of medial knee pain without mechanical symptoms that had recently worsened despite no acute inciting event. X-ray noted a possible osteochondritis dissecans (OCD) lesion of the distal medial right femoral condyle Case Photo #1 Case Photo #2 . MRI showed 9 x 7 mm osteochondritis dissecans (OCD) of the same location Case Photo #3 Case Photo #4 . She was instructed to discontinue impact exercises such as running and equestrian. She was permitted to cross train and was fitted in a hinged knee brace. At three month follow up, she was having minimal pain with the permitted activities and OCD lesion was healing well on x-ray Case Photo #5 Case Photo #6 . She was released to start graded return to activity, including running and equestrian. However, at one month follow up, she was experiencing persistent knee pain without effusion and new mechanical symptoms.

Physical Exam:
Patient appeared well and in no acute distress. Inspection of the right knee revealed no ecchymosis, effusion, or erythema. Gait was abnormal with a limp. Mild tenderness to palpation was noted along medial and lateral joint lines, medial and lateral patellar facets. Active range of motion was limited to 5-130 degrees. Muscle testing revealed 5/5 strength with knee flexion, knee extension, and hip flexion. J sign and crepitus of patella were present. Negative Lachman, anterior drawer, posterior drawer, medial McMurrays, and lateral McMurrays. Negative varus and valgus stress testing at 0 and 30 degrees. Distal pulses were 2+ and symmetric. Distal sensation was intact to pain and light touch.

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