Estimating minimal clinically important differences in primary elective total elbow arthroplasty using distribution-based methods.

BACKGROUND

Minimal clinically important differences (MCIDs) following primary total elbow arthroplasty (TEA) remain undefined, limiting interpretation of clinical benefit. This study aimed to determine TEA-specific distribution-based MCIDs from baseline variability in primary elective TEA cohorts and identify previously published MCIDs across elbow conditions.

METHODS

A systematic search identified primary elective TEA studies reporting baseline variability statistics. Pooled standard deviations (SD) estimated MCIDs via the half-SD method (all measures) and the one standard error of measurement method (multi-item scales). A scoping review identified published anchor- or distribution-based MCIDs. Outcomes assessed: pain visual analog scale, Mayo Elbow Performance Score (MEPS), Disabilities of Arm, Shoulder and Hand, Quick Disabilities of Arm, Shoulder and Hand, Oxford Elbow Score, and elbow range of motion.

RESULTS

Fifty-six studies contributed to baseline data. Half-SD-derived MCIDs were 1.0 point for pain visual analog scale, 11 points for MEPS, 15° for flexion-extension arc, and 20° for pronation-supination arc; the one-standard error of measurement-derived MCID for MEPS was 16 points. The scoping review identified no TEA-specific MCID studies and 9 across other elbow conditions, with wide variability.

CONCLUSION

These TEA-specific, distribution-based MCID estimates for pain, function, and range of motion offer a pragmatic framework for outcome interpretation, shared decision-making, and future research.