header advert
Orthopaedic Proceedings Logo

Receive monthly Table of Contents alerts from Orthopaedic Proceedings

Comprehensive article alerts can be set up and managed through your account settings

View my account settings

Visit Orthopaedic Proceedings at:

Loading...

Loading...

Full Access

General Orthopaedics

PREDICTING OUTSTANDING RESULTS AFTER REVERSE SHOULDER ARTHROPLASTY USING PERCENTAGE OF MAXIMAL OUTCOME IMPROVEMENT

International Society for Technology in Arthroplasty (ISTA) meeting, 32nd Annual Congress, Toronto, Canada, October 2019. Part 1 of 2.



Abstract

Background

The purpose of this study was to determine if thresholds regarding the percentage of maximal improvement in the Simple Shoulder Test (SST) and American Shoulder and Elbow Surgery (ASES) score exist that predict “excellent” patient s­atisfaction (PS) following reverse total shoulder arthroplasty (RSA).

Methods

Patients undergoing RSA using a single implant system were evaluated pre-operatively and at a minimum 2-year follow-up. Receiver-operating-characteristic (ROC) curve analysis determined thresholds to predict “excellent” PS by evaluating the percentage of maximal improvement for SST and ASES. Pre-operative factors were analyzed as independent predictors for achieving SST and ASES thresholds.

Results

198 (SST) and 196 (ASES) patients met inclusion criteria. For SST and ASES, ROC analysis identified 61.3% (p<.001) and 68.2% (p<.001) maximal improvement as the threshold for maximal predictability of “excellent” satisfaction respectively. Significant positive correlation between the percentage of maximum score achieved and “excellent” PS for both groups were found (r=.440, p<.001 for SST score; r=0.417, p<.001 for ASES score). Surgery on the dominant hand, greater baseline VAS Pain, and cuff arthropathy were independent predictors for achieving the SST and ASES threshold.

Conclusion

Achievement of 61.3% of maximal SST score improvement and 68.3% of maximal ASES score improvement represent thresholds for the achievement of “excellent” satisfaction following RSA. Independent predictors of achieving these thresholds were dominant sided surgery and higher baseline pain VAS scores for SST, and rotator cuff arthropathy for ASES.

Keywords

Percentage of maximal improvement; Predictors; American Shoulder and Elbow Surgery Score; Simply Shoulder Test; Reverse shoulder Arthroplasty; Satisfaction.

Level of Evidence

Level III