Comparison of Functional Outcomes Between Kinematic and Mechanical Alignment in Total Knee Arthroplasty: 7-Year Follow-Up

Karimi Mobarake, Mahmood; Rahimi, Yasin; Karimi, Alireza

doi:10.22034/ijos.2026.255211

Comparison of Functional Outcomes Between Kinematic and Mechanical Alignment in Total Knee Arthroplasty: 7-Year Follow-Up

Document Type : Original Article

Authors

Mahmood Karimi Mobarake ¹

yasin rahimi ²

Alireza Karimi ³

¹ Department of Orthopedics, School of Medicine, Kerman University of Medical Sciences

² Assistant in Orthopedic Surgery, Department of Orthopedics, Kerman University of Medical Sciences, Kerman, Iran

³ Student Research Committee, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.

https://doi.org/10.22034/ijos.2026.255211

Abstract

Background and Aim:
Total knee arthroplasty (TKA) is a standard treatment for advanced osteoarthritis. Mechanical alignment has long been the conventional approach, while kinematic alignment has been introduced to restore the native joint axis. This study aimed to compare functional outcomes of TKA performed with mechanical and kinematic alignment.

Materials and Methods:
This retrospective cohort study was conducted in 2024 at Mehregan and Arjomand Hospitals in Kerman, Iran. The study population included patients who underwent TKA between 2018 and 2023 using either mechanical or kinematic alignment performed by two knee specialists. Patient data were extracted from medical records, and functional outcomes were assessed using the Lysholm questionnaire. Statistical analyses were performed using SPSS version 23.

Results:
Two hundred patients were evaluated (100 in each group). In the kinematic group, 69% were female and 31% male, while in the mechanical group, 74% were female and 26% male. The mean age was 68.02 years in the kinematic group and 69.61 years in the mechanical group. The mean follow‑up duration was 51.37 months in the kinematic group and 53.41 months in the mechanical group. No significant differences were observed between groups regarding demographics. The mean Lysholm score was slightly higher in the kinematic group (85.18) compared to the mechanical group (84.40), but the difference was not statistically significant (p = 0.62). Subscale scores, including limping, walking aids, pain, instability, swelling, and squatting, showed no significant differences.

Conclusion:

Keywords

Knee joint replacement

mechanical method

kinematic method

Subjects