Comparison of Functional Outcomes of Two Knee Arthroplasty Techniques (Total Knee Arthroplasty and Unicompartmental Knee Arthroplasty) for the Treatment of Osteoarthritis, simultaneously done in the Same Patients

Document Type : RESEARCH PAPER

Authors

1 Department of Orthopedic, School of Medicine, Imam Hossein Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran

2 Student research Committee, Alborz University of medical sciences, Karaj, Iran

10.22038/abjs.2024.75050.3469

Abstract

Objectives: This study aims to provide a comprehensive comparative analysis of functional outcomes 
between Unicompartmental Knee Arthroplasty (UKA) and Total Knee Arthroplasty (TKA) in patients 
diagnosed with bilateral knee osteoarthritis. Both procedures were perform ed simultaneously on 
separate knees to evaluate their respective efficacy.
Methods: The study included 25 patients (18 women and 7 men) with a mean age of 59.6 years, all meeting the 
criteria for administering UKA on one knee and TKA on the other. Radiographic and clinical data were collected over 
a two-year period, with assessments conducted at 6 months, 1 year, and 2 years postoperatively. Data included 
age, gender, body mass index, medical history, surgical procedures, and various scores and measurements related 
to knee function.
Results: The UKA group exhibited significant improvements in functional scores compared to the TKA group. 
Specifically, the Western Ontario and McMaster Universities Osteoarthritis Index score for the UKA knee was 24.5% 
higher than that of the TKA knee, indicating better functional outcomes. Radiographically, the tibiofemoral angle was 
more than two times greater in the UKA method, while the varus angle was significantly greater in the TKA method. 
No post-operative complications were reported.
Conclusion: This study underscored the safety and efficacy of both UKA and TKA procedures in the treatment of 
bilateral knee osteoarthritis. UKA demonstrated superior functional outcomes, while TKA displayed distinct 
advantages in radiographic alignment. Individual patient characteristics and preferences should guide the selection 
of the most appropriate surgical approach.
 Level of evidence: IV

Keywords

Main Subjects


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