Purpose: There is controversial information on recovery of patients with compensable injuries. The purpose of this matched case-control study was to examine the impact of an active compensation claim following a work-related shoulder injury on reporting disability as measured by subjective and objective outcomes at 1 year post-operatively.

Method: Data of 506 consecutive patients who had undergone a decompression or rotator cuff repair were reviewed. One hundred and fourteen patients were on compensation related to their shoulder problems. Patients were matched with a historical control group (patients without a compensation claim) based on age (4 age groups: < 40, 40–49, 50–59, 60–70), sex, and pathology (full-thickness tear vs. no tear). Outcome measures used were a disease-specific outcome, the Western Ontario Rotator Cuff Index (WORC) and two shoulder specific instruments, the American Shoulder and Elbow Score (ASES) and the Constant Murley (CM) score. Paired and independent t-tests and an analysis of covariance were performed.

Results: Data of the 214 patients (72 males and 35 females in each group) was used for analysis (mean age 48, SD: 10, range 20–69). Out of 107 patients in each group, 42 patients (58%) had undergone a full-thickness repair and 65 (61%) had surgeries related to impingement syndrome. Paired and independent t-tests showed that both groups improved significantly regardless of their claim status. However, the compensation group had a significantly lower level of improvement than the non-compensation group. An analysis of covariance which adjusted for pre-operative differences in disability scores showed that an active claim was indeed a strong predictor of follow up scores.

Conclusion: This is the first study that has used a matched case-control design to control for potential confounding factors in injured worker population. Our results indicate that although patients with work-related injuries demonstrate a lower level of recovery, they still benefit from surgery.