Disease diagnosis and arthroplasty type are strongly associated with short-term postoperative patient-reported outcomes in patients undergoing primary total shoulder arthroplasty

Abstract

Background: Prognostic factors for total shoulder arthroplasty (TSA) clinical outcomes are incompletely understood. This study investigates the associations of preoperative patient, disease-specific, and surgical factors with 1-year postoperative PENN Shoulder Score (PSS) in patients undergoing primary TSA.

Methods: Cleveland Clinic patients undergoing primary anatomic TSA (aTSA) or reverse TSA (rTSA) for glenohumeral osteoarthritis (GHOA) or rotator cuff tear arthropathy (CTA) between February 2015 and August 2019, and having complete preoperative and 1-year postoperative patient-reported outcome measures (PROMs), were included. Twenty preselected preoperative patient, disease-specific, and surgical factors were used to fit multivariable models for 1-year PSS and its subscores.

Results: Of 1427 eligible primary TSAs, 1174 had 1-year follow-up by PROMs (82%), with 1042 analyzed after additional exclusions, including 30% rTSAs for CTA (n = 308), 26% rTSAs for GHOA (n = 275), and 44% aTSAs for GHOA (n = 459). All PROMs showed statistically significant improvements postoperatively, with 89% of patients reaching an acceptable symptom state. Lower 1-year PSS was associated with younger age, female sex, current smoking, chronic pain diagnosis, history of prior surgery, worker's compensation claim, lower preoperative mental health, lower baseline PSS, absence of glenoid bone loss, and diagnosis-arthroplasty type (CTA-rTSA < GHOA-rTSA < GHOA-aTSA). The most important prognostic factors associated with 1-year PSS were diagnosis-arthroplasty type, baseline mental health status, and insurance status.

Conclusions: Disease diagnosis, arthroplasty type, and several other baseline factors are strongly and individually associated with PROMs following primary TSA, with patients undergoing aTSA for GHOA demonstrating the highest PROM scores at 1-year follow-up. Patient, disease-specific, and surgical factors can be used to guide postoperative prognosis following primary TSA for improved preoperative patient counseling regarding expected outcomes of these procedures.

Keywords: Shoulder arthroplasty; beta regression model; cuff tear arthropathy; glenohumeral osteoarthritis; multivariable model; outcomes; patient-reported outcome measures.

Figure 1

Patient selection flow diagram for the primary shoulder arthroplasty surgical cohort. *Total number of cases matching 1 or more exclusion criteria. PROMs, patient-reported outcome measures; GHOA, glenohumeral osteoarthritis; CTA, cuff tear arthropathy; TSA, total shoulder arthroplasty; rTSA, reverse total shoulder arthroplasty; RC, rotator cuff.

Figure 2

Forest plot showing the estimated difference in means for pain and function subscores and total PENN Shoulder Score (PSS) and odds ratios for the satisfaction subscore, each with 95% confidence intervals, for predictors in the full models of patients undergoing primary shoulder arthroplasty. The effects for continuous variables (age, BMI, CCI, education, ADI, baseline VR-12 MCS, and baseline PSS) are comparing the 75th vs. 25th percentiles shown in Table II. Predictors or contrasts of categories of categorical predictors are regarded as statistically significant, and their respective estimated effect sizes are depicted in red, only if the corresponding overall test simultaneously assessing associations of all categories with the respective 1-year PSS score or subscore is statistically significant. BMI, body mass index; CCI, Charlson Comorbidity Index; ADI, Area Deprivation Index; VR-12 MCS, Veterans RAND 12-Item Health Survey mental component summary; F, female; M, male; CTA, cuff tear arthropathy; rTSA, reverse total shoulder arthroplasty; GHOA, glenohumeral osteoarthritis; aTSA, anatomic total shoulder arthroplasty; SP, superior-posterior.

Figure 3

Relative variable importance of patient demographic, disease-specific, and surgical characteristics on 1-year PSS total (A) and its subscores (Pain [B], Function [C], Satisfaction [D]), based on the increase in Akaike information criterion (AIC) on removal from the full model. Variables with the largest contribution to outcomes are listed at the top of the respective charts. VR-12 MCS, Veterans RAND 12-Item Health Survey mental component summary; PSS, PENN Shoulder Score; BMI, body mass index; SP, superior-posterior.