Clinical Assessments of Hand Function in First Carpometacarpal Osteoarthritis Do Not Appear to Correlate with Radiographic Findings

Abstract

Background

Thumb carpometacarpal (first CMC) osteoarthritis (OA), a degenerative process affecting hand use, is typically assessed by clinical examination and radiographs. This assessment determines treatment, but it may not reflect functional limitations.

Questions/Purposes

We aimed to explore the relationship between measures of hand function and radiographs in individuals with and without first CMC OA.

Methods

We designed a cross-sectional, observational pilot study, enrolling five patients with first CMC OA (nine thumbs with modified Eaton-Littler grades ranging from 1 to 4, using retrospective radiographic data) and nine healthy controls. They underwent evaluation of hand function using four patient-reported outcome measures (PROMs)—the Patient-Specific Functional Scale (PSFS); the Patient-Rated Wrist/Hand Evaluation (PRWHE); the Disabilities of the Arm, Shoulder, and Hand (DASH); and the Modified Score for the Assessment and Quantification of Chronic Rheumatoid Affections of the Hands (M-SACRAH)—and one performance measure, the Arthritis Hand Function Test (AHFT). Spearman's ρ with 95% subject clustered bootstrapped confidence intervals was calculated to assess for correlations between radiographic findings and measures of hand function.

Results

Only the DASH work score showed strong positive correlation with radiographic OA grade, with PSFS, PRWHE, M-SACRAH, and AHFT scores demonstrating low to moderate correlations. Notable differences were found between patients and control subjects in median scores of the DASH, PSFS, PRWHE, and M-SACRAH, as well as in the grip, pinch, and button scores of the AHFT.

Conclusion

While only the DASH work score strongly correlated with radiographic grade of first CMC OA, several measures detected considerable differences in functional hand use between patients and control subjects. The findings of this pilot study suggest that hand function scores be considered in addition to radiographs when determining severity of first CMC OA. The findings can also inform the design of a larger, powered study.