Early restoration of shoulder function in patients with the Grammont prosthesis compared to lateralized humeral design in reverse shoulder arthroplasty

Lateralization of the humerus in reverse total shoulder arthroplasty: can preoperative planning software predict postoperative lateralization and does lateralization influence outcomes?

BACKGROUND

Reverse total shoulder arthroplasty (RTSA) can result in varying amounts of humeral medialization or lateralization. The amount of medial or lateral change-in-arm-position can be predicted using 3D computed tomography planning software. It is not clear if the preoperatively predicted change-in-arm-position correlates with the actual radiographically measured change-in-arm-position or if the predicted or actual change-in-arm-position correlates with patient-reported outcomes or complications.

METHODS

Patients who received RTSA underwent preoperative 3D computed tomography planning to predict the postoperative medial-to-lateral change-in-arm-position (PCAP). Preoperative and postoperative radiographs were used to calculate the actual medial-to-lateral change-in-arm-position using the measurement of the lateral edge of the greater tuberosity to the lateral edge of the acromion (RCAP-LHO). The Western Ontario Osteoarthritis Score (WOOS), American Shoulder and Elbow Surgeons score (ASES), and Single Assessment Numeric Evaluation (SANE) were recorded at baseline, 1 year, and 2 years. Rates of complications were recorded.

RESULTS

A total of 250 patients were eligible for this study including 189 patients reaching the 1-year clinical follow-up point and 144 patients reaching the 2-year clinical follow-up point. One-year and 2-year follow-up rates were 89% and 91%, respectively. The mean PCAP was 3 ± 5 mm and the mean RCAP-LHO was 1 ± 8 mm. There was a moderate correlation between PCAP and RCAP-LHO. There was a weak correlation between increased PCAP lateralization and higher WOOS and ASES at 2 years and an improvement from baseline to 2 years in WOOS. There was a very weak correlation between increased PCAP lateralization and improvement compared with baseline in 1-year SANE and improvement compared with baseline in 2-year SANE. There was a weak correlation between lateralized RCAP-LHO and 2-year postoperative SANE. There was superior 2-year WOOS, ASES, and SANE, and improvement in SANE at 1 year compared with baseline in patients with a lateralized PCAP compared with a medialized or neutral PCAP. There was superior 2-year WOOS, improvement in WOOS from baseline to 2-year follow-up, and 2-year SANE in patients with a lateralized RCAP-LHO compared with a medialized or neutral RCAP-LHO. Overall complication rates were similar between groups although the dislocation rate in shoulders with a lateralized change-in-arm-position was significantly less than that in shoulders with a medial or neutral change-in-arm-position.

CONCLUSIONS

PCAP correlated with actual RCAP-LHO. Correlations exist with increased humeral lateralization and improved patient-determined outcomes. Patient-determined outcomes in patients with a lateralized change-in-arm-position were the same as or better than those with a medialized or neutral change-in-arm-position. A lateralized change-in-arm-position did not result in increased overall complications and was protective against postoperative instability.

The effect of lateralization and distalization after Grammont-style reverse total shoulder arthroplasty

BACKGROUND

The purpose of this study was to evaluate the relationship between multiple radiographic measures of lateralization and distalization and clinical outcome scores after a reverse total shoulder arthroplasty (RTSA).

METHODS

We retrospectively evaluated all RTSAs performed by the senior author between January 1, 2007, and November 1, 2017. We then evaluated the visual analog scale for pain (VAS pain), Simple Shoulder Test (SST), and American Shoulder and Elbow Surgeons (ASES) scores and complication and reoperation rates at a minimum of 2-year follow-up. We measured preoperative and postoperative (2-week) radiographs for the lateralization shoulder angle (LSA), the distalization shoulder angle (DSA), lateral humeral offset, and the distance from the glenoid to the lateral aspect of the greater tuberosity. A multivariable analysis was performed to evaluate the effect of the postoperative radiographic measurements on final patient-reported outcomes (ASES scores, SST, and VAS pain).

RESULTS

The cohort included 216 shoulders from unique patients who had patient-reported outcome scores available at a minimum of 2-year follow-up (average, 4.0 ± 1.9 years) for a total follow-up rate of 70%. In the multivariable models, more lateralization (LSA) was associated with worse final ASES scores -0.52 (95% confidence interval [CI]: -0.88, -0.17; P = .004), and more distalization (DSA) was associated with better final ASES scores 0.40 (95% CI: 0.11, 0.69; P = .007). More lateralization (LSA) was associated with worse final SST scores -0.06 (95% CI: -0.11, -0.003; P = .039). Finally, greater distalization (DSA) was associated with lower final VAS pain scores, ratio = 0.98 (95% CI: 0.96, 1.00; P = .021).

CONCLUSIONS

Greater distalization and less lateralization are associated with better function and less pain after a Grammont-style RTSA. When using a Grammont-style implant, remaining consistent with Grammont's principles of implant placement will afford better final clinical outcomes.

Reverse Total Shoulder Arthroplasty Using Lateralized Glenoid Baseplates Has Superior Patient-determined Outcome Scores at Short-term Follow-up

INTRODUCTION

There are a variety of baseplate options when performing reverse total shoulder arthroplasty (RTSA). Currently, there is no consensus on the optimal glenoid baseplate. The hypothesis of this study was that the use of lateralized baseplates would improve patient-determined outcomes and postoperative range of motion after RTSA compared with standard baseplates without increasing the risk of complications.

METHODS

Patients undergoing RTSA were stratified into a standard baseplate group (SBG) and a lateralized baseplate group (LBG). The LBG included 3 mm lateralization, 6 mm lateralization, and full-wedge augmentation (8 mm lateralization). The Western Ontario Osteoarthritis Score, American Shoulder and Elbow Surgeons score, Single Assessment Numeric Evaluation (SANE), and Simple Shoulder Test (SST) were recorded at baseline, 1 year, and 2 years. Range of motion was recorded at baseline and 1 year. Differences in complications between groups were recorded.

RESULTS

The LBG included 187 patients, and the SBG included 51 patients. No difference was observed in any patient-determined outcome score at 1-year follow-up. At 2 years, there were greater Western Ontario Osteoarthritis Score (84 ± 16 versus 74 ± 19; P = 0.01), American Shoulder and Elbow Surgeons score (81 ± 15 versus 70 ± 20; P = 0.001), SST (8.0 ± 2.4 versus 6.6 ± 2.6; P = 0.007), and SANE (82 ± 17 versus 68 ± 25; P = 0.0005). The improvement in SST (5.0 ± 2.7 versus 3.3 ± 3.6; P = 0.02) and SANE (54 ± 26 versus 37 ± 30; P = 0.004) at 2 years compared with baseline was greater in the LBG compared with the SBG. No difference was observed in any range-of-motion metric between groups. Total complications were similar between groups ( P = 0.91). Scapular notching was more prevalent in the SBG (7.8% versus 1.6%; P = 0.01).

CONCLUSION

The LBG had better patient-determined outcome scores compared with the SBG at 2-year follow-up with a similar rate of overall complications but a lower rate of scapular notching. Range of motion was not improved by the use of a lateralized baseplate compared with a standard baseplate.

Postoperative complications of reverse total shoulder arthroplasty: a multicenter study in Japan

Background

Reverse total shoulder arthroplasty (RSA) has been approved since 2014 in Japan, and the number of RSA cases has been accumulating. However, only short-to medium-term outcomes have been reported, with a small number of case series, because of its short history in Japan. This study aimed to evaluate complications after RSA in hospitals affiliated with our institute, with comparison to those in other countries.

Methods

A multicenter retrospective study was performed at 6 hospitals. In total, 615 shoulders (mean age: 75.7 ± 6.2 years; mean follow-up: 45.2 ± 19.6 months) with at least 24 months of follow-up were included in this study. The active range of motion was assessed pre-and postoperatively. The 5-year survival rate was evaluated for reoperation for any reason in 137 shoulders with at least 5 years of follow-up using Kaplan-Meier analysis. Postoperative complications were evaluated, including dislocation; prosthesis failure; deep infection; periprosthetic, acromial, scapular spine, and clavicle fractures; neurological disorders; and reoperation. Furthermore, imaging assessments, including scapular notching, prosthesis aseptic loosening, and heterotopic ossification were evaluated on postoperative radiography at the final follow-up.

Results

All range of motion parameters were significantly improved postoperatively (P < .001). The 5-year survival rate was 93.4% (95% confidence interval: 87.8%-96.5%) for reoperation. Complications occurred in 256 shoulders (42.0%), with reoperation in 45 (7.3%), acromial fracture in 24 (3.9%), neurological disorders in 17 (2.8%), deep infection in 16 (2.6%), periprosthetic fracture in 11 (1.8%), dislocation in 9 (1.5%), prosthesis failure in 9 (1.5%), clavicle fracture in 4 (0.7%), and scapular spine fracture in 2 (0.3%). Regarding imaging assessments, scapular notching was observed in 145 shoulders (23.6%), heterotopic ossification in 80 (13.0%), and prosthesis loosening in 13 (2.1%).

Conclusion

This is the first large case series to investigate the complications after RSA in Japan, and the overall frequency of complications after RSA was similar to that in other countries.

The Role of Humeral Neck-Shaft Angle in Reverse Total Shoulder Arthroplasty: 155° versus <155°—A Systematic Review

The aim of this study was to have updated scrutiny of the influence of the humeral neck-shaft angle (HNSA) in patients who underwent reverse shoulder arthroplasty (RSA). A PRISMA-guided literature search was conducted from May to September 2021. Clinical outcome scores, functional parameters, and any complications were reviewed. Eleven papers were identified for inclusion in this systematic review. A total of 971 shoulders were evaluated at a minimum-follow up of 12 months, and a maximum of 120 months. The sample size for the "HNSA 155°" group is 449 patients, the "HNSA 145°" group involves 140 patients, and the "HSNA 135°" group comprises 291 patients. The HNSA represents an important variable in choosing the RSA implant design for patients with rotator cuff arthropathy. Positive outcomes are described for all the 155°, 145°, and 135° HSNA groups. Among the different implant designs, the 155° group show a better SST score, but also the highest rate of revisions and scapular notching; the 145° cohort achieve the best values in terms of active forward flexion, abduction, ASES score, and CMS, but also the highest rate of infections; while the 135° design obtains the best results in the external rotation with arm at side, but also the highest rate of fractures. High-quality studies are required to obtain valid results regarding the best prosthesis implant.

Medialized versus Lateralized Center of Rotation in Reverse Total Shoulder Arthroplasty: A Systematic Review and Meta-Analysis

One of the original biomechanical principles of reverse total shoulder arthroplasty (RTSA) is medialization of the center of rotation (COR) relative to the native level of the glenoid. Several authors have proposed the lateralized center of rotation, which is characterized by a lateralized (L) glenoid and medialized (M) humeral component. The aim of this review is to compare the clinical and functional outcomes of COR in medialized (M-RTSA) and lateralized (L-RTSA) RTSA in patients with uniform indications and treatment through a meta-analysis. A PRISMA-guided literature search of PubMed, Medline, Embase, Scopus, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews and Cochrane Clinical Answers was conducted from April to May 2021. Twenty-four studies were included in the qualitative synthesis, and 19 studies were included in the meta-analysis. Treatment with RTSA resulted in positive post-operative outcomes and low complication rates for both groups. Statistically relevant differences between L-RTSA group and M-RTSA group were found in post-operative improvement in external rotation with arm-at-side (20.4° and 8.3°, respectively), scapular notching rates (6.6% and 47.7%) and post-operative infection rates (1% and 7.7%). Both lateralized and medialized designs were shown to improve the postoperative outcomes. Nevertheless, a lateralized COR resulted in greater post-operative external rotation.