Abstract
Purpose
To examine measurement properties of four disability outcomes in patients with advanced osteoarthritis of the glenohumeral joint.
Methods
This was a prospective longitudinal study of patients with advanced osteoarthritis of the glenohumeral joint who underwent a Total Shoulder Arthroplasty (TSA) and were followed for 6 months. Four measures [Western Ontario Osteoarthritis Shoulder (WOOS) Index, the American Shoulder and Elbow Surgeons (ASES) assessment, Constant-Murley score (CMS), and Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH)] were completed 2-3 weeks before surgery and at 6 months after surgery.
Results
Seventy-seven patients (average age: 66, range 35 to 86, 60% women, 40% men) participated in the study. The Cronbach's Coefficient Alpha of subjective measures was high at 0.91, 0.86, and 0.83 for WOOS, ASES, and QuickDASH respectively. All measures were able to discriminate between men and women's levels of disability at p< 0.05. Correlations between pre-operative scores were moderate (0.59 to -0.79) and slightly increased post-operatively (0.61 to -0.87). All measures were sensitive in detecting change in the disability status over a period of 6 months.
Conclusion
All four disability measures were reliable and valid for use in patients with advanced osteoarthritis of the glenohumeral joint. Outcome measurement in busy clinics can be facilitated by choosing valid and reliable measures that have the advantage of simplicity for use by patients and clinicians. The consensus-based standards for selection of outcome measures have been developed for hip and knee arthritis and need to take place for the shoulder joint. Developing consensus by an international group of experts will improve consistency in using outcome measures in patients with shoulder problems.