Summary

The purpose of this study was to describe PROMIS scores in patients who underwent Bankart repair for anterior instability and to determine if preoperative PROMIS scores could predict which patients would attain a Minimally Clinically Important Difference (MCID) postoperatively.

Abstract

Background

PROMIS (Patient Reported Outcomes Measure Information System) is a high-throughput PROM (patient reported outcome measure) that has shown validity and accuracy in characterizing patients who undergo surgery for shoulder instability. It is unknown whether preoperative PROM scores can predict postoperative outcomes in shoulder instability patients.
Objectives: The purpose of this study was to describe PROMIS scores in patients who underwent Bankart repair for anterior instability and to determine if preoperative PROMIS scores could predict which patients would attain a Minimally Clinically Important Difference (MCID) postoperatively.

Methods

A retrospective analysis of PROMIS scores in patients who underwent primary Bankart repair from February 2015 to February 2017 at our institution was performed. Patients were included if they had a primary diagnosis of anterior shoulder instability, a documented dislocation/subluxation event, and PROMIS scores both within 60 days prior to surgery and from 14-180 days after surgery. Patients were excluded if they had previously undergone any shoulder instability surgery, were Worker’s Compensation or had a subacromial decompression and acromioplasty performed at the time of Bankart repair. PROMIS physical function (PF), pain interference (PI) and depression (D) scores from preoperatively and postoperatively were compared. MCID was determined to be +4.6, -4.4, -4.4 for PF, PI and D, respectively. Accuracy analyses were performed to determine whether preoperative PROMIS scores from each domain could predict postoperative achievement of MCID in the same domain. A second analysis was performed by adding clinical factors (age, gender, surgeon) to the logistic regression model. Preoperative PROMIS cutoff scores were calculated.

Results

71 patients met criteria and were included in the final analysis. Mean age was 22.4. Preoperative (mean 32 days prior to surgery) and postoperative (mean 78 days after surgery) PROMIS scores are seen in Table 1. There was a statistically significant decrease in PI postoperatively (p = 0.001), but no significant changes in PF or D. Preoperative PF and D scores showed a strong ability to predict postoperative achievement of MCID, with accuracy analyses yielding an area under the curve (AUC) of 0.84 and 0.77, respectively. Preoperative PI did not show a strong predictive ability. Preoperative cutoff scores representing a 95% chance of achieving MCID (“95% MCID”), as well as scores representing a 95% chance of failing to achieve MCID (“95% No MCID”) are shown in Table 1. The secondary analysis adding age, gender and surgeon to the regression model showed stronger predictive abilities for all domains, including PI, with AUCs of 0.89, 0.78, 0.80 for PF, PI and D, respectively.

Conclusions

PROMIS PI showed significant improvement in patients who underwent Bankart repair for anterior instability. Preoperative PROMIS PF and D scores were highly predictive of outcomes in the early postoperative period. When clinical factors were added to the analysis, all preoperative PROMIS domains showed strong predictive ability of postoperative outcomes. The 95% MCID values provide powerful cutoffs to predict which patients are most and least likely to achieve MCID after surgery. These cutoffs can be directly applied by orthopedic surgeons to stratify patients based on their preoperative PROMIS scores, specifically to identify those patients at highest risk for having poor outcomes. This information will not only help surgeons counsel their patients, but also helps patients maintain realistic expectations and maximize patient satisfaction after shoulder instability surgery.