Abstract
Purpose
With growing attention being paid to quality and cost effectiveness in healthcare, outcome evaluations are becoming increasingly important. This determination can be especially difficult in reverse shoulder arthroplasty (RSA) given the complex pathology and extensive disabilities in this patient population. Several different scoring systems have been developed and validated for use in various shoulder pathologies. The purpose of this study was to assess the use three outcome scores in a population of patients undergoing RSA. We aim to demonstrate the validity of three outcome scores in patients undergoing RSA, and to determine if one score or a combination of scores is superior to others.
Methods
Using a database of patients treated with RSA, we assessed preoperative and postoperative Constant Scores, American Shoulder and Elbow Surgeons (ASES) scores, and subjective shoulder values (SSV) in 148 shoulders. The outcomes at each scoring period were described and the scores were compared to one another as well as to active range of motion using linear regression modeling.
Results
There were no significant differences in the mean improvement of any of the scores. All of the outcome scales improvements were correlated with each other and improvement in forward elevation but not with external rotation. Using multivariate regression analysis all 3 outcome measures were able to predict 38.9% of the variation in improvement in functional outcomes (forward elevation). This was only slightly greater than that provided by improvements in the outcome variable CS alone (36.7%).
Conclusion
The three shoulder outcome scores evaluated, regardless of whether they were patient reported or physician based, appear to appropriately reflect improvements after RSA with equal validity. The objective physician assessed Constant score had the strongest correlation with function of the arm, and use of a combination of all 3 outcome scores does not increase the ability to predict range of motion compared to using the Constant Score alone.
