Total Knee Arthroplasty in Valgus Deformity Made Easy Using Robotic-assisted Predictive Balancing Technique

Abstract

Total knee arthroplasty (TKA) performed for valgus osteoarthritis (OA) presents a challenge to the arthroplasty surgeon in regards to achieving appropriate soft tissue balance and alignment. Robotic assisted surgery (RAS) with navigation (NAV) has been proposed as a potential solution to assist surgeons when performing these difficult cases. Here, we present the case of a complex primary TKA in a patient with posttraumatic valgus arthritis performed using a novel RAS system with NAV. Appropriate balance was unable to be achieved with bony cuts alone, as the knee was found to be tight laterally in extension following bone preparation. Soft tissue releases were ultimately required. Use of the novel RAS system with NAV allowed for a titrated soft tissue release resulting in a balanced knee without overcorrection of the patient’s deformity. We also present a similar case of a patient with valgus knee OA in which there was residual tightness laterally in flexion. The different management strategies for each of these cases is discussed. Finally, we provide a review of the available literature regarding TKA in valgus knee OA and propose a new classification system and treatment algorithm that can be employed using a novel RAS system with predictive balancing technology to achieve optimal alignment and soft tissue balancing in valgus knees that remain unbalanced following bony cuts.