Author: Alan Nicotra, DO
Co Author #1: Alan Nicotra, DO
Co Author #2: Elizabeth Winton, MD
Senior Editor: Drew Duerson, MD
Editor: Shayne Fehr, MD

Patient Presentation:
A 41 year-old male presented to the sports medicine clinic for atraumatic left knee pain.

History:
He had a recent history of left first metatarsophalangeal joint pain and left anterior ankle pain and swelling. He subsequently developed left knee pain and swelling and hip pain a week prior to presentation. He was first seen at an urgent care. He was treated with an intramuscular corticosteroid injection and a nonsteroidal anti-inflammatory drug(NSAID) which was followed by an oral corticosteroid taper. His symptoms initially improved but then returned. He then presented to the sports medicine clinic with left knee pain located laterally without radiation. He denied any prior fevers, systemic symptoms, knee redness, mechanical symptoms, or a prior diagnosis of gout. He reported being sexually active and was concerned about a sexually transmitted infection as he endorsed an abnormal urinary stream. He denied any prior history of STIs, knee injuries, or joint pains.

Physical Exam:
His vital signs were normal.
General: The patient was a well-appearing male in no acute distress.
Musculoskeletal: His gait was antalgic.
A large left knee effusion was present without erythema or significant warmth. The knee was tender to palpation over the lateral femoral condyle and lateral joint line. He had tenderness to palpation over left anterior ankle joint without effusion. His active and passive range of motion of the left knee was 10 to 100 degrees. His extensor mechanism was intact. Valgus instability and pain was noted at 30 degrees. McMurray's and Patellar Grind test was painful.

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