Kinematic Alignment Technique Outperforms Mechanical Alignment in Simultaneous Bilateral Total Knee Arthroplasty: A Randomized Controlled Trial

Mohammad Mahdi Sarzaeem; Mohammad Movahedinia; Alireza Mirahmadi; Mansour Abolghasemian; Mahdi Tavakoli; Farzad Amouzadeh Omrani

doi:10.1016/j.arth.2024.03.045

Kinematic Alignment Technique Outperforms Mechanical Alignment in Simultaneous Bilateral Total Knee Arthroplasty: A Randomized Controlled Trial

J Arthroplasty. 2024 Mar 25:S0883-5403(24)00261-4. doi: 10.1016/j.arth.2024.03.045. Online ahead of print.

Authors

Mohammad Mahdi Sarzaeem¹, Mohammad Movahedinia², Alireza Mirahmadi², Mansour Abolghasemian³, Mahdi Tavakoli⁴, Farzad Amouzadeh Omrani¹

Affiliations

¹ Department of Orthopedic Surgery and Traumatology, Imam Hossein Medical Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
² Bone, Joint and Related Tissue Research Center, Akhtar Orthopedic Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
³ Division of Orthopedic Surgery, University of Alberta, Edmonton, AB, Canada.
⁴ Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB, Canada.

PMID: 38537837
DOI: 10.1016/j.arth.2024.03.045

Abstract

Background: The aim of this study was to compare the clinical results of kinematic alignment (KA) with those of mechanical alignment (MA) in single-stage bilateral total knee arthroplasty.

Methods: In this double-blinded randomized controlled trial, 65 patients who had bilateral knee osteoarthritis underwent simultaneous bilateral total knee arthroplasty. One knee was randomly selected to be operated on with the calipered-KA technique and the other with MA. The participants were assessed via the Oxford Knee Score, Western Ontario and McMaster Universities Osteoarthritis Index questionnaire, and visual analog scale before the surgery and the same plus the Forgotten Joint Score at their last follow-up visit, 2 years postoperatively. Maximum knee flexion and the time reaching maximum knee flexion, named the recovery time, were also recorded. Hip-knee-ankle angle, medial proximal tibial angle, and lateral distal femoral angle were measured before and after the surgery using 3-joint-view radiographs.

Results: At 2 years, there were significant differences between the KA and MA techniques in terms of duration of surgery, recovery time, and final Western Ontario and McMaster Universities Osteoarthritis Index, Forgotten Joint Score, and maximum flexion range in favor of KA (P < .05), but no significant difference in visual analog scale score or Oxford Knee Score. In patients who have a preferred knee, the KA knee was preferred over the MA knee by most patients. No prosthetic failure or revision was reported in either group.

Conclusions: The KA technique yields acceptable functional outcomes compared to the MA technique. The KA technique was associated with a shorter surgery time, a faster recovery time, and higher patient satisfaction in 2-year follow-ups. Larger multicenter studies with longer follow-ups are warranted to confirm these findings.

Level of evidence: I.

Keywords: kinematic alignment; knee arthroplasty; mechanical alignment; outcome; randomized controlled trial; simultaneous bilateral arthroplasty.