Total Knee Arthroplasty for A Young Patient: An Unusual Case of Ankylosing Spondyloarthropathy with Gouty Arthritis

Introduction: Total knee arthroplasty (TKA) is more commonly accepted in the elderly population, however, a gradual increase in cases of total knee arthroplasty in young patients has shown good patient satisfaction, and improved mean knee society clinical and functional scores. Among young patients (less than 50 years old) who were treated with total knee arthroplasty, pre-operative diagnosis remains to be due to: primary osteoarthritis, post-traumatic arthritis or due to severe inflammatory arthropathy. (1, 2, 7). The diagnosis of inflammatory arthropathy may include different chronic inflammatory conditions such as: rheumatoid arthritis (which is the most common and most studied), Psoriatic arthritis, Seronegative Ankylosing Spondylitis and Gouty arthritis among others. (1,3) Although the spectrum of inflammatory arthropathy is commonly grouped together, the identification of the cause of the inflammatory arthropathy will be important in the overall approach and management of a patient.

Case Report: This is a case of a 39-year-old male with a ten-year history of bilateral knee pain. The patient became sedentary due to difficulty in ambulation and knee stiffness. On physical examination, the patient is wheelchair-bound, has no knee effusion, ROM left knee: 40-70 degrees; right knee: 55-83 degrees only. Positive patellar compression test, both knees. Symmetrical chest expansion, 3 cm diaphragmatic excursion. He had negative RF and Anti-CCP, uric acid elevated at 499 IU/L, ESR elevated at 20, HLA-B27: Positive. A diagnosis of Ankylosing Spondyloarthropathy with Gouty Arthritis was made. The patient underwent a bilateral TKA using a standard medial parapatellar approach and a posterior stabilized Wright system. Intraoperatively, there was severe adhesions of patellofemoral and tibiofemoral joint with synovitis and tophi on both knees. Soft tissue release was done on medial, lateral and posterior compartment. Femoral component size 4 and tibial component size 3 and 12 cm spacer for both knees was used. Postoperatively, patient was able to stand on post-op day 2. Physical rehabilitation was continued with ROM 10- 100 degrees for both knees on post-op day 7. At one-month post-op, he was able to ambulate with a cane and has a ROM of 5-110 degrees on the left and 10-110 degrees on the right with very good patient satisfaction and a Knee Society score of 85/100 from 40/100.

Conclusion: Young patients with severe contracture and functional limitation and an unusual cause of combined Ankylosing Spondyloarthropathy and Gouty inflammatory arthritis may still expect good outcomes with improved patient quality of life after total knee arthroplasty.