Dr. Meyer: The patient is a 19-year-old girl who was well until one year prior to admission, when she noted the gradual onset of intermittent, mild pain in her right knee. This continued to be an annoying but tolerable symptom until she fell on the knee one month prior to admission, after which the pain was constant but still mild. The findings of roentgenographic examination of the knee at this time prompted referral to the hospital for evaluation.
Results of physical examination were entirely normal. There was no pain on deep palpation of the distal right femur. There was no swelling, joint effusion, or redness.
Dr. Richard C. Pfister: Dr. Shea, would you discuss this case?Dr. Thomas E. Shea: The roentgenograms of the right knee show a 5 × 7-cm lesion in the distal femur (Fig 1). The abnormality is metaphyseal in location, extending into the diaphysis and