Evaluation of anteroposterior accelerometric change after bi-cruciate stabilized total knee arthroplasty and posterior stabilized total knee arthroplasty

Background: In conventional total knee arthroplasty (TKA), the anterior cruciate ligament (ACL) is resected. ACL dysfunction causes knee instability and is regarded as one factor in poor TKA outcomes. In bi-cruciate stabilized (BCS) TKA, the implant reproduces ACL function and provides anterior stability. The objective of this study was to evaluate preop-erative and postoperative X-rays and accelerometer gait measurements in patients who underwent BCS TKA and posterior-stabilized (PS) TKA to assess the postoperative acceler-ation changes of knees after these procedures and to compare them in terms of joint range of motion (ROM) and the New Knee Society Score (New KSS). Methods: The subjects were 60 patients, 30 of whom underwent BCS TKA and 30 PS TKA. Joint ROM, New KSS, lateral X-rays of the standing extended knee, and accelerometer data were evaluated 12 months postoperatively. Results: There was no significant difference in joint ROM between the groups. Both had good New KSS results, but the functional activity score was significantly higher after BCS TKA than after PS TKA. X-rays showed a lower posterior offset ratio after BCS TKA than after PS TKA, with anteroposterior positioning closer to that of the normal knee. Accelerometer data showed that postoperative anteroposterior acceleration on the femoral side in the stance phase and swing phase was lower after BCS TKA than after PS TKA. Conclusion: Compared with PS TKA, BCS TKA resulted in a higher functional activity score, closer positioning to that of the normal knee on lateral X-ray, and lower anteroposterior acceleration on the femoral side. (c) 2021 Elsevier B.V. All rights reserved.