Knee Surg Relat Res.  2018 Mar;30(1):23-27. 10.5792/ksrr.17.042.

Intentionally Increased Flexion Angle of the Femoral Component in Mobile Bearing Unicompartmental Knee Arthroplasty

• Cho KY
• Kim KI
• Song SJ
• Kim KJ

• KMID: 2407506
• DOI: http://doi.org/10.5792/ksrr.17.042

Abstract

PURPOSE
The purpose of this study was to determine the results of mobile bearing unicompartmental knee arthroplasty (UKA) with an intentionally increased flexion angle of the femoral component in patients requiring high flexion.
MATERIALS AND METHODS
We investigated 45 knees treated by UKA. Clinically, we measured the range of motion (ROM) and the American Knee Society (AKS) score preoperatively and at final follow-up and investigated complications. Radiologically, we measured the flexion angle of the femoral component, the posterior slope angle of the tibial component, the femorotibial angle and mechanical axis of the limb postoperatively.
RESULTS
The ROM was increased from 123° preoperatively to 139° at the final follow-up. The AKS knee and function scores increased from 59 and 68, respectively, preoperatively to 94 and 96, respectively, at the final follow-up. The flexion angle of the femoral component was 9.1°, and the posterior slope angle of the tibial component was 8.6°. There was one case of bearing dislocation in the largest femoral flexion angle case.
CONCLUSIONS
The results might reflect the positive effect of an increased flexion angle of the femoral component up to 10° on ROM in mobile bearing UKA, which would contribute to better quality of life after UKA especially in populations requiring deep knee flexion.

Keyword

Knee; Arthroplasty; Unicompartmental; Flexion angle; Femoral component; Range of motion

MeSH Terms

Arthroplasty
Arthroplasty, Replacement, Knee*
Dislocations
Extremities
Follow-Up Studies
Humans
Intention*
Knee
Quality of Life
Range of Motion, Articular