Quality and Rate of Recovery after Simpliciti Anatomic Total Shoulder Arthroplasty and Tornier Pyrocarbon Hemiarthroplasty: A Propensity Score-Matched Comparative Study.

Abstract

Simpliciti anatomic total shoulder arthroplasty (aTSA) and Tornier Pyrocarbon hemiarthroplasty (PyroC-HA) have been utilized with predictable benefit for the treatment of glenohumeral osteoarthritis (GHOA). The purpose of this study was to compare the rate of recovery and 2-year clinical outcomes in a matched group of patients undergoing these procedures. Prospectively collected preoperative, 3-, 6- and 24-month data were obtained from two Investigational Device Exemption studies evaluating the outcomes of patients who underwent stemless aTSA or PyroC-HA (n=157 each). A 1:1 propensity-score match was performed based on gender, age, BMI, diagnosis, glenoid morphology, baseline American Shoulder and Elbow Surgeon (ASES) and adjusted Constant scores. Seventy-four patients were identified for each cohort with no significant differences in covariates (all p>.103). Final outcome, change from baseline, and number of patients meeting the Minimal Clinically Important Difference (MCID) were evaluated for ASES score, total Constant, Constant strength, and pain score (0-10 scale). At baseline, each cohort (n=74) included 63 males (85%), and the primary diagnosis was GHOA in all patients. The average age of the aTSA cohort was 60.8 ± 7.3 years and 58.9 ± 6.6 years in the PyroC-HA cohort (p=0.103). Walch A1 was the most prevalent glenoid type in both cohorts (38% of aTSA patients and 45% of PyroC-HA). At 2 years there were 68 aTSA patients and 71 PyroC-HA patients included in the analysis. No significant differences in ASES scores were noted at any time point except for the 6 month score, which favored aTSA (83.5 points vs. 77.5, p=0.031). Average total Constant scores were not significantly different at any compared time point. There was a less than 1 point difference in pain between aTSA and PyroC-HA which was statistically significant at the 6-month and 24-month timepoints, with aTSA reporting an average pain level of 1.1 ± 1.5 compared to 1.8 ± 2.0 (p=0.018) at 6-months and 0.45 ± 0.95 vs. 1.06 ± 1.84 at 24-months (p=0.016). A statistically equivalent percentage of patients from each group achieved the MCID for ASES, Constant, and pain scores. Simpliciti aTSA and Tornier PyroC-HA are effective surgical treatments for younger patients with GHOA with similar outcomes at short-term follow-up. This study demonstrated that patients experienced similar recoveries and nearly identical two-year outcomes, with the exception of a statistically significant, less than 1 point difference in pain at 24 months postoperative.