Purpose: There is little information in the literature regarding outcomes of unicompartmental knee arthroplasty (UKA) in patients receiving worker’s compensation (WC). The purpose of the present study is to compare the outcomes of UKA in patients receiving WC compared to patients without WC.

Methods: Nineteen patients with a WC claim treated by UKA for medial compartment arthritis were compared to twenty patients who underwent similar procedure but had no WC claim. Average follow up period was 37 months (range 30–60 months). Outcomes were evaluated using Knee Society Score (KSS) data. T test was used for statistical analysis. Comparisons were also made with respect to conversion in to total knee arthroplasty (TKA).

Results: WC patients improved from a mean preoperative KSS of 47.4 (range 30–70) to 76.9 (range 55–99), while non-WC patients improved from 43.3 (range 35–63) to 90.7 (range 74–100). The difference in improvement between the two groups was statistically significant (p=0.004). Furthermore, the postoperative KSS in the non-WC patients was significantly higher than that of the WC group (p=0.007). There was no significant difference between the incidences of conversion to TKA between the two groups.

Conclusions: These findings suggest that patients with WC claims have poorer outcomes after UKA in comparison to non-WC patients.