Octogenarians Undergoing Medial Unicompartmental Knee Arthroplasty Have Similar Patient-Reported Outcomes as Their Younger Counterparts

As a procedure with lower surgical morbidity, unicompartmental knee arthroplasty (UKA) may present a practical solution for elderly patients with unicompartmental arthritis. However, few studies have analyzed the results of UKA in the extreme elderly. This study compared the functional and perioperative outcomes between octogenarians and age-appropriate controls undergoing UKA.

Prospectively collected data of 44 patients aged ≥80 years who underwent unilateral UKA were analyzed. Each octogenarian was matched 1:3 with 132 patients aged 65-74 years using propensity scores adjusting for gender, body mass index, Charlson comorbidity index, and preoperative scores. Knee Injury and Osteoarthritis Outcome Score for Joint Replacement and Short Form-12 were collected preoperatively and 2 years postoperatively. Complications, reoperations, readmissions, and unplanned visits were recorded up to 1 year postoperatively.

The mean age was 70.0 ± 2.7 years in the control group and 83.0 ± 3.0 years in the octogenarian group (P < .001). The percentage of outpatient procedures was comparable (control 50.0%; octogenarian 45.5%; P = .601). With the exception of poorer Short Form-12 physical scores in octogenarians at 2 years (39.4 ± 14.1 vs 44.9 ± 9.2, P = .028), there was no difference in final postoperative scores or improvement in scores between the groups. The rate of complications, reoperations, readmissions, and emergency room visits was also similar. The five-year survivorship was 97% in the control group and 93% in the octogenarian group (P = .148).

Octogenarians undergoing UKA can experience clinical outcomes that are similar to those of their younger counterparts. The clinical trajectory outlined may help clinicians provide valuable prognostic information to elderly patients and guide preoperative counseling.