Is It Water On The Knee?! Operation!

Abstract

HISTORY: A 53-year-old male with history of knee osteoarthritis presented with worsening right knee pain 2.5 months following MVA. He also noted a mobile mass over the superior lateral knee. There was no relief with NSAIDs or rest. PHYSICAL EXAMINATION: Antalgic gait with crutches. Right knee with moderate effusion, limited range of motion to 100 degrees flexion and 10 degrees extension with crepitus, tenderness to palpation over the lateral joint line with a palpable mass superior to the lateral femoral condyle. Positive McMurray’s test. DIFFERENTIAL DIAGNOSIS: 1. Osteoarthritis flare2. Meniscal tear3. Avulsion fracture of the femur4. Crystalline arthropathy5. Synovial osteochondromatosis TEST AND RESULTS: Right Knee X-Ray: Linear bony density along the medial femoral condyle, suspicious for an acute to subacute avulsion fracture. Stable findings of synovial osteochondromatosis. Synovial Fluid Analysis: No organisms or crystals identified. Right Knee MRI without contrast: Tricompartmental osteoarthritis with secondary synovial osteochondromatosis with large calcified intra-articular body within the suprapatellar recess measuring 4.7 cm. Moderate joint effusion. Moderate synovitis. Medial and lateral complex meniscal tears. Pellegrini-Stieda lesion, compatible with sequela of prior MCL injury without periligamentous edema. FINAL WORKING DIAGNOSIS: Synovial osteochondromatosis with a large loose body with underlying osteoarthritis and medial and lateral complex meniscal tears. TREATMENT AND OUTCOMES: Aspiration was performed for 47 cc serous synovial fluid followed by intra-articular corticosteroid injection. At 3 week follow-up visit, the patient noted 50% improvement in pain, but recurrent effusion and increased buckling. Case was discussed with an orthopedic surgeon and recommendation was made for loose body excision and possible total knee arthroplasty. After discussion, the patient preferred to avoid surgery and continue conservative care with bracing and physical therapy.