Persistent Knee Swelling After Fall - Walking

Abstract

HISTORY: 45 year old female with hip dysplasia, status post bilateral hip replacements in 2004, who fell directly onto her left knee approximately one month ago. Diagnosed with prepatellar bursitis and since initial presentation has been drained twice and received a corticosteroid injection once. Denies discomfort, catching, locking, and feelings of instability. Complains that fluid is annoying with ambulation but denies pain. No previous history of knee trauma or swelling. Denies history of fevers, chills, fatigue, rashes, and increased warmth or redness of left knee. Patient denies family history of musculoskeletal conditions. PHYSICAL EXAM: Standing examination reveals severe pes planus and approximately 20 degrees of genu valgus bilaterally. Large collection of fluid appreciated on the anteromedial aspect of left knee. No ecchymosis or erythema appreciated. With supine examination no effusion appreciated. Fluid mobile and fluctuant, distributed over the pes anserinus, medial joint line, and medial hamstring. Fluid collection extends to prepatellar region with palpation. No tenderness with palpation of joint lines, patellar facets, or patellar tendon. Flexion to 110 degrees and extension to zero degrees. Negative lachmans, negative varus and valgus stresses at both zero and 30 degrees. Negative McMurrays. DIFFERENTIAL DIAGNOSIS: 1. Prepatellar bursitis 2. Pes Anserine bursitis 3. Occult fracture 4. Ligamentous or Meniscal injury 5. Inflammatory arthropathy 6. Gout TESTS AND RESULTS Bilateral 45 degree PA, bilateral Merchant, and lateral view left knee -medial soft tissue swelling, medial joint space narrowing, mild degenerative changes -moth eaten pattern of lateral femoral condyle MRI left knee without contrast -prominent distension of prepatellar bursa 8.1 × 8.1 × 1.6 cm -Lateral femoral condyle OCD lesion measuring 1.7 by 3 cm FINAL WORKING DIAGNOSIS -Prepatellar bursitis -Large lateral femoral condyle OCD TREATMENT AND OUTCOMES -After MRI prepatellar bursal swelling drained, 89 ml of serosanguineous fluid aspirated and 40 mg of corticosteroid injected -Provided with knee sleeve for compression -Patient referred for surgical consultation of OCD lesion