Two-year results of a multi-centre, randomized controlled trial comparing a second-generation uncemented trabecular metal-backed versus cemented polyethylene glenoid component in total shoulder arthroplasty

Abstract

Aims To report early (two-year) postoperative findings from a randomized controlled trial (RCT) investigating disease-specific quality of life (QOL), clinical, patient-reported, and radiological outcomes in patients undergoing a total shoulder arthroplasty (TSA) with a second-generation uncemented trabecular metal (TM) glenoid versus a cemented polyethylene glenoid (POLY) component. Methods Five fellowship-trained surgeons from three centres participated. Patients aged between 18 and 79 years with a primary diagnosis of glenohumeral osteoarthritis were screened for eligibility. Patients were randomized intraoperatively to either a TM or POLY glenoid component. Study intervals were: baseline, six weeks, six-, 12-, and 24 months postoperatively. The primary outcome was the Western Ontario Osteoarthritis Shoulder QOL score. Radiological images were reviewed for metal debris. Mixed effects repeated measures analysis of variance for within and between group comparisons were performed. Results A total of 93 patients were randomized (46 TM; 47 POLY). No significant or clinically important differences were found with patient-reported outcomes at 24-month follow-up. Regarding the glenoid components, there were no complications or revision surgeries in either group. Grade 1 metal debris was observed in three (6.5%) patients with TM glenoids at 24 months but outcomes were not negatively impacted. Conclusion Early results from this RCT showed no differences in disease-specific QOL, radiographs, complication rates, or shoulder function between uncemented second-generation TM and cemented POLY glenoids at 24 months postoperatively. Revision surgeries and reoperations were reported in both groups, but none attributed to glenoid implant failure. At 24 months postoperatively, Grade 1 metal debris was found in 6.5% of patients with a TM glenoid but did not negatively influence patient-reported outcomes. Longer-term follow-up is needed and is underway. Cite this article: Bone Jt Open 2021;2(9):728–736.

Glenoid Component Position Does Not Affect Short-Term Clinical and Radiologic Outcomes in Total Shoulder Arthroplasty

“…Patients included in the current study were part of a prospective, randomized controlled multi-center study comparing two glenoid components [10]. This study was a retrospective analysis of prospectively collected data.…”

“…Patients presenting to one of five shoulder surgeons between June 2012 and December 2016 were screened for eligibility [10]. Inclusion criteria were age and primary glenohumeral osteoarthritis (GH-OA).…”

“…Inclusion criteria were age and primary glenohumeral osteoarthritis (GH-OA). Exclusion criteria were patients with significant glenoid bone loss on a pre-operative CT scan or intra-operatively, major joint trauma, avascular necrosis, rotator cuff or inflammatory arthropathy, chronic dislocations, massive cuff tear, previous shoulder surgery (other than arthroscopic debridement or acromioplasty), active joint or systemic infection, muscle paralysis, Charcot arthropathy, life expectancy <2 years or who were unable to read or speak English [10].…”

“…Randomization was performed using a central data center (EmPOWER Health Research; London, ON, Canada) which was responsible for generating the randomization codes, which were stratified by the surgeon. All patients received an uncemented Bigliani-Flatow humeral prosthesis (Zimmer Biomet; Warsaw, IN, USA) [10].…”

“…Surgical techniques and postoperative details are described in Chin et al [10]. In the literature, glenoid version averages about 1.23 • retroversion with a range from −9.5 to 10.5 • [11] and average inclination angles are approximately 1.3 • (range from −3 to 7 • ) [12].…”