Predicting outcomes after total knee arthroplasty using intraoperative knee kinematics measured by navigation

Objectives The objective of the study is to evaluate the relationship between clinical results following posterior-stabilized total knee arthroplasty (TKA) and intraoperative kinematic pattern determined from navigation. Methods Participants were patients with knee osteoarthritis and varus deformity who underwent primary posterior-stabilized TKA. Preoperative and post-implantation kinematic data were recorded, and all kinematic patterns were divided into two types: medial pivot (MP) or non-MP. Knees with MP and non-MP patterns after implantation were compared in terms of postoperative flexion angle, pain, patient satisfaction, expectations, and activity using the new Knee Society Score 2011 at 1 year postoperatively. Results This study involved 55 patients (12 men, 43 women) with a mean age of 73.1 years and mean body mass index of 26.5 kg/m(2). Preoperative kinematic measurements showed MP in 23 knees and non-MP in 32 knees. After implantation, navigation showed MP in 25 knees and non-MP in 30 knees. No significant differences were found between kinematic patterns preoperatively and after implantation. Postoperative flexion angle, pain, patient satisfaction, expectations, and activity using Knee Society Score 2011 showed no differences between MP and non-MP knees. Conclusion Intraoperative knee kinematics as measured by navigation could not predict postoperative outcomes of TKA.