J Korean Orthop Assoc.  2021 Feb;56(1):34-41. 10.4055/jkoa.2021.56.1.34.

Clinical Results of Medial Unicompartmental Knee Arthroplasty in Elderly Patients Older than 70 Years of Age

• Kim KT
• Lee S
• Kim JH
• Lee HY
• Kim MJ

• KMID: 2512894
• DOI: http://doi.org/10.4055/jkoa.2021.56.1.34

Abstract

Purpose
To evaluate the long-term clinical results and survivorship of unicompartmental knee arthroplasty (UKA) in elderly patients older than 70 years by analyzing cases that have been implanted for >10 years ago.
Materials and Methods
The long-term follow-up results were evaluated in 39 patients (46 cases) who underwent medial UKA from March 2002 to February 2004. The mean age of the patients at the time of surgery was 74.0 years, and the preoperative diagnosis was degenerative arthritis of the knee in all cases.
Results
Of the 46 cases, reoperation occurred due to the complications in four cases. In 22 cases without 14 cases of death and six cases of follow-up loss, follow-up more than 10 years was possible. The mean Knee Society knee and function scores improved significantly from 53.0 and 52.5 points pre-operatively to 89.4 and 80.9 points at the last follow-up, respectively (p<0.001). The mean range of motion of the knee recovered to 132.5°, and the mean tibiofemoral angle changed to 5.9° of valgus at the last follow-up. Complications following the UKA occurred in four cases; the most prevalent complication was mobile bearing dislocation (n=2). One case of failure occurred due to aseptic loosening and degenerative arthritis of the lateral compartment, respectively. The cumulative survival rate of the implants was 95.0% at 10 years and 85.7% at 15 years. Of the 40 cases, excluding six cases of follow-up loss, 36 cases (90.0%) could be used without reoperation until death or at the last follow-up after surgery.
Conclusion
These results showed the outstanding functions of the knee and satisfactory long-term survivorship after UKA. Therefore, UKA could be a useful method for the treatment of osteoarthritis of the knee in elderly patients older than 70 years of age.

Keyword

knee; osteoarthritis; unicompartmental knee arthroplasty; survivorship; elderly