Author: George Le, MD
Co Author #1: Bernadette Pendergraph, M.D.
Senior Editor: Kristine Karlson, MD, FAMSSM
Editor: Sean Wise, MD

Patient Presentation:
A 56-year-old man presented for bilateral knee pain.

History:
A 56-year-old man with past medical history including hypertension, hyperlipidemia, and empty sella syndrome with hypogonadism, presented for bilateral knee pain. While playing basketball with his children 11 days ago, he leapt up into the air to catch an errant pass, landed on his flexed right knee, heard a pop, landed on his flexed left knee, felt immediate pain in both knees, and then fell to the ground. Afterwards he was unable to ambulate and bear weight due to the pain. He reported bruising on his lateral right thigh and medial left thigh. He was seen at an outside facility where he was placed in bilateral knee immobilizers and referred to physical therapy. Of note, an MRI obtained 13 months previously had shown a partial ACL tear of the right knee, patellar tendinopathy, and possible tear of the posterior horn of the medial meniscus.

Physical Exam:
On examination in sports medicine, the patient showed resolving ecchymosis at the distal lateral right thigh and distal medial left thigh. There was 2+ effusion in the right knee and 1+ effusion in the left knee. His right knee range of motion was 0 to 90 degrees, with tenderness at the medial and lateral joint lines as well as at the quadriceps tendon, patella, and patellar tendon. His left knee range of motion was 0 to 95 degrees, with tenderness at the medial and lateral joint lines as well as at the quadriceps tendon. Lachman test was positive in the right knee and negative in the left knee. Extensor lag was present in both knees. The remainder of the exam was limited by pain.

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