Medium-Term Clinical and Radiographic Results of an All-Polyethylene, Pegged, Bone-Ingrowth Glenoid Component: A Concise Follow-up of a Previous Report

Medium-Term Clinical Outcomes of the Global Icon Stemless Shoulder System: Results of a 2-Year Follow-Up

The primary aim of this study was to assess the medium-term outcomes of the Global Icon stemless shoulder replacement in patients who have undergone primary total shoulder arthroplasty (TSA) for glenohumeral joint osteoarthritis. A retrospective review of patients who had undergone a TSA using the Global Icon stemless shoulder system was performed. The Western Ontario Osteoarthritis Shoulder (WOOS) Index and Oxford Shoulder Score (OSS) were evaluated pre-operatively and at 12 to 24 months post-operatively. Radiological outcomes, operation time, and post-operative complications were reported. Primary analysis for the WOOS Index and OSS focused on detecting within-group treatment effects at 24 months using a repeated measures ANOVA. Thirty patients were included in the study. Post-surgery, there was a significant improvement at 24 months on the OSS (ES = 0.932, CI: 41.7 to 47.7, p < 0.001) and the WOOS Index (ES = 0.906, CI: 71.9 to 99.8, p < 0.001). Radiographs revealed that no component loosened, migrated, or subsided. The median operative time was 75.5 (IQR: 12.25, range: 18 to 105) min. No implant-related complications were reported. The Global Icon stemless replacements have excellent clinical outcomes in this cohort at 12- and 24-month follow-up with no implant-related complications.

Total shoulder replacement stems in osteoarthritis-short, long, or reverse? An analysis of the impact of crosslinked polyethylene

BACKGROUND

The 2021 Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) report indicated that total shoulder replacement using both midhead (TMH) length humeral components and reverse arthroplasty (RTSA) had a lower revision rate than stemmed humeral components in anatomic total shoulder arthroplasty (aTSA)-for all prosthesis types and diagnoses. However, there are many factors that affect the outcome of total shoulder replacement, including stem length and polarity, polyethylene type, and glenoid fixation (cemented vs. cementless). The aim of this study was to assess the impact of these variables in the various primary total arthroplasty alternatives for osteoarthritis (OA) in the shoulder.

METHODS

Data from a large national arthroplasty registry were analyzed for the period April 2004 to December 2020. The study population included all primary aTSA, RTSA, and TMH shoulder arthroplasty procedures undertaken for OA using either crosslinked polyethylene (XLPE) or noncrosslinked polyethylene (non-XLPE). Because of the previously documented and reported higher revision rate compared with other anatomic total shoulder replacement options, those using cementless metal-backed glenoid components were excluded. The rate of revision was determined by Kaplan-Meier estimates, with comparisons by Cox proportional hazard models. Reasons for revision were also assessed.

RESULTS

For a primary diagnosis of OA, aTSA with a cemented XLPE glenoid component had the lowest revision rate, with a 12-year cumulative revision rate of 4.7%, compared with aTSA with cemented non-XLPE glenoid component at 8.7% and RTSA at 6.8%. The revision rate for TMH (with XLPE or non-XLPE) was lower than aTSA with cemented non-XLPE but was similar to the other implants at the same length of follow-up. The reason for revision of cemented aTSR was most commonly component loosening, not rotator cuff deficiency.

CONCLUSION

Long-stem humeral components matched with XLPE in aTSA achieve a lower revision rate compared with shorter stems, long stems with conventional polyethylene, and RTSA when used to treat shoulder OA. In all these cohorts, loosening, not rotator cuff failure, was the most common diagnosis for revision.