Ankle Pain–Volleyball Player

HISTORY: An otherwise healthy 24 year old female volleyball player presented to the sports medicine clinic with a two week history of atraumatic severe left ankle pain and swelling. She localized the pain to her tibiotalar area. She described a sensation of “tightness” in the ankle. She denied any numbness or tingling or mechanical features to her pain, and she denied focal weakness. She did not endorse any other swollen or painful joints. She denied any history of autoimmune disease, inflammatory arthritis, or exposure to ticks. She had tried Ibuprofen and Tylenol with no significant relief. PHYSICAL EXAMINATION: Exam revealed a left ankle effusion and tenderness to touch over the anterior tibial-talar joint but not on the medial, lateral or posterior ankle. No laxity was noted with anterior drawer test. External rotation stress test was not painful. No pain was produced with resisted ankle motion in all planes. Neurologic exam did not reveal any focal strength or sensory changes in the lower extremities. Distal pulses and capillary refill were symmetric. DIFFERENTIAL DIAGNOSIS: 1. Septic Arthritis 2. Inflammatory Arthritis/Synovitis 3. Crystalline Monoarthritis 4. Lyme Arthritis 5. Internal Derangement 6. Occult Fracture 7. Pigmented Villonodular Synovitis 8. Synovial Chondromatosis TEST AND RESULTS: Laboratory testing showed normal white blood cell count. Sedimentation rate and C-reactive protein were slightly elevated. Lyme disease ELISA, rheumatoid factor, and CCP were all negative. X-ray showed left ankle effusion but no fractures. Attempted ultrasound guided aspiration showed extensive tibiotalar synovitis but did not produce any fluid for analysis. MRI of the left ankle showed extensive nodular synovial thickening of the anterior compartment consistent with Diffuse PVNS. FINAL WORKING DIAGNOSIS: Diffuse Pigmented Villonodular Synovitis(PVNS) TREATMENT AND OUTCOMES: 1. Modest improvement of pain with activity reduction 2. Orthopedic Foot and Ankle Surgery consult for planned arthroscopic nodule excision and synovectomy