Intra-Operative and Anatomic Verification of a TKA Computational Model for Pre-Operative Surgical Planning

Abstract

A promising measure of dynamic outcomes in Total Knee Arthroplasty (TKA) is the simulation of joint dynamics. These simulations are potentially useful for pre-operative planning, but are not yet validated for patient-specific variations in anatomy, which forms the aim of this paper. 284 patients from a database of total knee arthroplasty patients were analysed using a pre-operatively defined simulation predicting post-operative knee dynamics; each patient had previously undergone pre- and post-operative CT imaging and had been assessed using the Knee Injury and Osteoarthritis Outcome (KOOS) score at 6 months following surgery. A significant correlation was found between the simulated contact force and laxity in mid-flexion (r=-0.452, p<0.0001), and between the medio- lateral difference in contact force and difference in distal-vs-posterior femoral collateral ligament offset (r=-0.473, p<0.0001). A significant difference of 5 KOOS pain points (p=0.02) was found for patients with unusually low or high simulated contact force compared to normal. These results indicate the preoperative simulation is capable of distinguishing patient-specific kinematics prior to surgery, thereby demonstrating the utility of this simulation for making pre-surgical predictions of patient-specific kinematics and patient-reported outcomes.