Specificity and responsiveness of patient-reported and clinician-rated outcome measures in the context of elbow surgery, comparing patients with and without rheumatoid arthritis.

OBJECTIVES: To examine and contrast the ability of patient-reported and clinician-rated measures, reflecting different levels of specificity, to detect differences in outcomes between patients with and without rheumatoid arthritis (RA), at 6 months following elbow surgery.
METHODS: One hundred and four consecutive patients/elbows self-completed the Oxford Elbow Score (OES), Disabilities of the Arm, Shoulder and Hand (DASH) and SF-36 general health questionnaires prior to elbow surgery. A surgeon assessed the standard Mayo Elbow Performance Score (MEPS) and recorded patients' diagnoses. Assessments were repeated 6 months following surgery in an outpatient clinic. Patients also completed pain "transition" and global satisfaction items. Patients who did not attend completed their assessment by post.
RESULTS: Twenty-three (22%) patients had RA. These patients were more likely than other patients to have bilateral elbow problems and to have total elbow replacement (85.7% versus 10.5% P<0.001). Patients with RA had more severe preoperative elbow-specific scores, and experienced a large and significantly greater amount of change in elbow function, as measured by the OES function (P=0.002) and pain scales (P=0.013). The surgeon-assessed elbow-specific MEPS score also detected a large and significant difference between the two groups (P<0.001). However, these differences were not detected by the upper limb specific DASH, by any SF-36 general health dimensions, or by transition or satisfaction items.
CONCLUSIONS: The OES performed well in assessing surgical outcomes in patients with RA. Neither the upper limb specific DASH nor the SF-36 is specific or responsive enough to warrant its exclusive use as an outcome measure for elbow surgery. LEVEL OF EVIDENCE: Level II (prospective non-randomised study).