Abstract
Constrained implants have become more common in difficult primary total knee arthroplasty (TKA) cases in recent years because they may more effectively and conveniently handle the substantial instability that is evident in osteoarthritis of knees with severe varus deformity. However, the need for a constrained TKA in such conditions is controversial, as constraint implants come with a bargain of stability for longitivity. In this case report, we have successfully shown that even in cases of significant instability and bone loss, intraoperative conversion to a restricted device is rarely necessary. In our case report, a 83-year-old female had complaints of severe pain in bilateral knees, with the right knee more than the left knee, since 12 years with severe varus deformity in the right knee. Physical examination revealed swelling and medial joint line tenderness with restriction of range of motion in bilateral knees. Pre-anesthetic checkup of the patient was done and patient was given clearance for surgery under American Society of Anesthesiologist (ASA)-2, total knee arthroplasty with a long stem was done, extreme varus deformity was corrected, osteophytes removed and tibial bone loss was repaired with bone cement. Post operatively patient showed significant improvement and McMaster University and Western Ontario Osteoarthritis Index (WOMAC) and Knee Society Scores (KSS) for pain, stiffness, and physical function during everyday activities were significantly improved compared to pre-operative assessment.