English

Abstract

The main indication of total knee replacement (TKR) is pain and restricted range of motion of the knee. The key to a successful total knee replacement is correct alignment in flexion and extension. Here we report a case of TKR in severe osteoarthritis (O / A) knee with a large cyst on the medial side of the knee, resulting in the problem of ligament balancing and management with help of an Arthrex Internal brace. Proper diagnosis and treatment plan help to overcome the challenging cases of varus knee. The indication of total knee replacement is pain and restricted range of motion of the knee. Several authors have reported successful outcomes on patient satisfaction in the follow-up of almost ten to fifteen years. 1 Additionally, the results of surgery are satisfactiry with good implant survival. 2 But some patients indeed have poor results and some may require revision surgery in a short duration. The key to a successful total knee replacement is correct alignment and stability in flexion and extension.3 The ligament after balancing of the correctly aligned knee must consider the function of the resected ligaments in flexion and extension, because in TKR both anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) are usually sacrificed. In other words, total knee replacement is a soft tissue surgery in which bone is replaced. In the varus knee, medial side structures are tight and compensatory laxity on the lateral side. So knee stability should be managed by the remaining ligamentous structures that are both medial and lateral collateral and capsular ligaments. 4 The gap technique is the gold standard for ligament balancing in total knee replacement. 5 That is the execution of equal medial and lateral gaps as well as balanced flexion and extension gaps. This is usually obtained by medial side release in varus knee as the medial side is contracted and lateral side release in valgus knee accordingly. Here we report a case of TKR in severe osteoarthritis knee with a large cyst on the medial side of the knee, resulting in the problem of ligament balancing and management.