What is the effect of supervised rehabilitation regime vs. self-management instruction following unicompartmental knee arthroplasty? – a pilot study in two cohorts

PURPOSE: The optimal rehabilitation strategy after a unicompartmental knee arthroplasty (UKA) is unclear. This study aims to compare the effect of transitioning from a supervised to a self-management rehabilitation regime by pilot study of patient outcomes subsequent to UKA surgery. METHODS: Fifty consecutive patients scheduled to undergo unilateral UKA surgery at our institution between 22(nd) February 2016 and 18(th)of January 2017 were prospectively identified via local medical database and included. Performed UKAs were grouped into two cohorts, Supervised Cohort and Self-management Cohort, temporally separated by introduction of new rehabilitation. Self-management Cohort(n = 25) received an extensive inpatient rehabilitation regime along with outpatient referral to rehabilitation center. The Self-management Cohort(n = 25) were only instructed in use of crutches and free ambulation at own accord. Follow-up (F/U) was 1 year from receiving UKA. A range of outcomes were recorded, and between-cohort differences compared: knee joint range of motion, pain and functional limitations, length of stay (LOS), readmission rate, pain during activity and rest, and knee circumference. RESULTS: Complete data was obtained for n = 45 patients. The mean between-cohort difference in ROM (range of motion) from preoperatively to discharge was 15.4 degrees (CI:5.2,25.8, p = 0.004), favoring the supervised regime, with no difference detected in any outcome at 3- or 12 months F/U. Median LOS was 1 day in both cohorts. CONCLUSION: Transition to a simple rehabilitation regime following UKA surgery was associated with decreased ROM at discharge, which was not present at 3-month F/U. We found no other between-cohort differences for any other outcomes at 3- and 12-month F/U including functional limitations, although the study was likely underpowered for these outcomes. We encourage large-scale replication of these findings using randomized designs. LEVEL OF EVIDENCE: Therapeutic level II