Knee Pain In An Avid Fitness Enthusiast

HISTORY: 42 year old male with a history of gout, localized to great toes, 3-4 flares per year, and on Colchicine referred by Neurology for 2 years of progressive right greater than left knee pain that worsened over the past few months. Pain was located over the patella, no radiation, and worse in the morning or with walking. Associated with stiffness, decreased range of motion, and difficulty with weight-bearing for which he would toe-walk or use crutches for support. No feelings of instability, catching, locking, or muscle weakness. He also reported low back pain and stiffness. No radiculopathy. No bowel/bladder incontinence. He failed oral NSAID and had no relief from a recent corticosteroid injection. PHYSICAL EXAMINATION: Afebrile. Toe-walking gait. Swelling in bilateral knees and a palpable effusion. Right knee had a superolateral moderate firm nodule. Tender along medial and lateral joint line. Limited range of motion with flexion to 50 degrees and extension to 15 degrees. Strength 5/5 with flexion and extension. Negative Valgus, Varus, Lachman’s, and Mcmurray’s. Sensation intact. Pulses present. Absent bilateral patellar and achilles reflexes. No tenderness to palpation along lumbar midline or paraspinal muscles. Negative slump test. DIFFERENTIAL DIAGNOSIS: Ankylosing Spondylosis, Rheumatoid Arthritis, Pigmented Villonodular Synovitis, Gout, Inflammatory Myositis TEST AND RESULTS: CMP, CBC, Hepatitis panel, ANA, Myositis panel, B12, Folate, Protein Electrophoresis, Sjogrens panel, Vitamin D, dsDNA, HLAB27, RNF, Anti CCP, Anti Ro all normal. CK 281, CRP 15.8, ESR 48, RF 16. MRI R Knee heterogeneous intra-articular soft tissue along the lateral suprapatellar pouch. MRI R Femur showed 5.3 cm enhancing mass in the medial patellar retinaculum and distal myotendinous junction of the vastus medialis extending into the medial suprapatellar recess. Surgical Pathology: Gouty tophus FINAL WORKING DIAGNOSIS: Chronic Gout with Tophi TREATMENT AND OUTCOMES: Patients symptoms improved after arthroscopy with open excision of tophus where extensive crystal formation was noted throughout the knee. Rheumatology started him on Allopurinol along with a low dose steroid. Most recent uric acid 6.8 with plans to repeat in 6 weeks. Patient will start physical therapy to work on range of motion and strength.