Author: Stephen Spadafore, MD
Co Author #1: Armando Vidal, MD
Co Author #2: Morteza Khodaee, MD, MPH
Editor: Daniel Murphy, MD
A healthy 28 year old male presents to a primary care clinic for a painful mass in his right knee that has enlarged over the past 9 months.
A 28 year-old otherwise healthy male presents for a painful mass on his right knee Case Photo #1. The patient has had worsening chronic right knee pain for 12 years. He first noticed the pain while playing high school football but does not remember any specific injury. The pain has been intermittent with episodes of locking and buckling. Over the past 9 months, he has noticed a slowly developing painful mass on the anterolateral aspect of the knee Case Photo #2. He plays bass guitar professionally and has noticed increased pain in the mass following each show. The mass does not seem to fluctuate in size or respond to ice, heat, or compression.
Gait is normal. There is a 4cm x 1.5 cm mass over the lateral right knee at the joint line that is firm and tender to palpation. There is no fluctuance, warmth, or erythema. Flexion and extension is intact, but he has pain at the end of flexion. There is no gross joint effusion or ligamentous laxity. McMurray, Thessaly, and patellar grind tests are negative. There is no medial joint line tenderness. Case Photo #1 Case Photo #2
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