Soft tissue tension in cruciate-retaining and posterior-stabilized total knee arthroplasty.

Using a tensor for total knee arthroplasty (TKA) designed to facilitate soft tissue balance measurements with a reduced patellofemoral joint, we intraoperatively compared the soft tissue tension of cruciate-retaining (CR) and posterior-stabilized (PS) TKAs performed at 0°, 10°, 45°, 90°, and 135° of flexion, with the patella both everted and reduced in 40 osteoarthritic patients. Although balance of soft tissue tension with a reduced patella of PS TKA slightly increased in varus from extension to flexion, these values slightly decreased for CR TKA from extension to flexion. Accordingly, we conclude that soft tissue tension patterns differ between everted and reduced patellae, as well as between PS and CR TKA.