Reverse Total Shoulder Arthroplasty with a Superior Augmented Glenoid Component for Favard Type-E1, E2, and E3 Glenoids

Abstract

Background: Uncorrected superior glenoid wear in patients managed with reverse total shoulder arthroplasty (rTSA) can result in increased complications, including baseplate failure. The present study quantifies the clinical and radiographic outcomes of patients with Favard type-E1, E2, and E3 glenoid deformity who were managed with rTSA with use of a superior or superior/posterior augmented glenoid baseplate. Methods: We retrospectively reviewed the records for 68 patients with shoulder arthritis and Favard type-E1, E2, or E3 glenoid deformity who were managed with primary rTSA and a 10° superior augmented or 10° superior/8° posterior augmented baseplate. The mean duration of follow-up was 40 months (range, 24 to 85 months). Outcomes were assessed preoperatively and at the latest follow-up with shoulder range of motion and use of outcome scores including the Simple Shoulder Test (SST), University of California Los Angeles (UCLA) score, American Shoulder and Elbow Surgeons (ASES) score, Constant score, and Shoulder Pain and Disability Index (SPADI) score. Radiographs were evaluated preoperatively and at the time of the latest follow-up. Differences in preoperative and postoperative range of motion and outcome metrics were assessed with use of a 2-tailed Student t test. Results: The majority of patients experienced clinically meaningful improvements in terms of pain and function following rTSA with a superior or superior/posterior augment, with 94% of patients rating themselves as “much better” (73.5%) or “better” (20.5%) at the time of the latest follow-up. At least 88% of the patients exceeded the minimum clinically important difference (MCID) threshold, and 75% of patients exceeded the substantial clinical benefit (SCB) threshold, for each of the clinical outcome metrics and range of motion. Five complications were reported (prevalence, 7.4%), including acromial stress fracture (2 patients), posttraumatic scapular neck fracture (1 patient), chronic shoulder pain (1 patient), and aseptic glenoid loosening (1 patient). Conclusions: The present short-term clinical and radiographic study demonstrated that shoulder arthropathy with superior glenoid wear patterns (Favard types E1, E2, and E3) can be successfully treated with rTSA with a superior or superior/posterior augmented baseplate. Longer-term clinical and radiographic follow-up is necessary to confirm that these promising short-term results are durable. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Management of glenoid bone loss in primary reverse shoulder arthroplasty

“…A total of 13 retrospective cohort studies, case series, and prospective cohort studies comprising 919 patients were included with 919 shoulders analyzed (Table I). 4,5,7,32-40 The mean age of patients at their initial evaluation was 72.2 years (42 to 87). The mean follow-up was 40.7 months (24 to 120).…”

“…ten studies presented clinical examination findings to report preoperative and postoperative rOm measurements (Figures 2 to 5). 4,5,[32][33][34][35][38][39][40]45 metaanalysis of these included studies demonstrated a significant increase in forward flexion at follow-up (mean difference (MD) 58.5° (95% confidence interval (CI) 51.5° to 65.4°); p < 0.001; Figure 2). From subgroup analysis, an improvement was seen in both bone graft and augmented prosthesis groups.…”

Reverse Shoulder Arthroplasty Biomechanics

“…Augmented glenoid baseplates were designed to conserve glenoid bone, increase prosthesis surface contact area with cortical bone, and better restore the native joint line when performing rTSA in eroded scapular morphologies [41,44,45]. Positive clinical results have been reported with augmented baseplates in a variety of types of eroded glenoids [83,[88][89][90][91]. Alternatively, bone grafting the glenoid can be used to lateralize the joint line.…”

The Evolution of Reverse Total Shoulder Arthroplasty—From the First Steps to Novel Implant Designs and Surgical Techniques

“…Jones et al compared autologous glenoid bone grafting with the use of metal-augmented baseplates, suggesting that both designs showed favorable results in addressing large defects and improved clinical outcomes. However, metal-augmented baseplates may result in lower rates of scapular notching with similarly lower complications such as graft resorption and glenoid baseplate loosening [ 59 , 60 , 61 , 62 ]. Recently, Nabergoj et al reported of satisfying clinical and radiological outcomes in patients with RTSA and concomitant bony and metallic augmentation for severe glenoid bone loss compared to patients with bony glenoid augmentation only [ 63 ].…”