Comparison of Lateralized Versus Medialized Reverse Total Shoulder Arthroplasty: A Systematic Review and Meta-analysis

Background: Reverse total shoulder arthroplasty (rTSA) is an established procedure for cuff tear arthropathy. More lateralized prostheses have been designed to overcome the reported adverse outcomes of Grammont-style rTSA. Purpose: To compare the clinical and radiological outcomes of medialized and lateralized center of rotation (COR) in rTSA. Study Design: Systematic review; Level of evidence, 3. Methods: This review followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Included were studies with a level of evidence ≥3 that compared medialized and lateralized rTSA with a minimum follow-up of 12 months. Functional scores including the American Shoulder and Elbow Surgeons (ASES) score and Constant score (CSS), range of motion at final follow-up, gain of external rotation (ER), visual analog scale (VAS) pain score, scapular notching, and heterotopic ossification (HO) were compared. Data were analyzed using random-effects or fixed-effects models in accordance with heterogeneity. Results: Five retrospective cohort studies and 1 randomized controlled study (n = 594 patients) were included. Lateralized rTSA resulted in greater improvement in ER degree ( P < .001), a lower VAS pain score (standardized mean difference [SMD], –0.39; P = .002), and a lower rate of scapular notching (risk ratio [RR], 0.40; P < .001) and HO (RR, 0.52; P < .001). Final forward flexion (SMD, –0.14; P = .629) and ER (SMD, 0.21; P = .238) did not differ significantly between the 2 groups. Overall functional scores, including ASES score (SMD, 0.22; P = .310) and CSS (SMD, 0.37; P = .077), also did not differ significantly (SMD, 0.28; P = .062). The overall complication rate did not differ significantly between the 2 groups (RR, 0.71; P = .339). Conclusion: Compared with medialized rTSA, lateralized COR rTSA results in greater improvement in ER and the VAS pain score, decreased rates of scapular notching and HO, and no significant changes in functional outcome scores or the complication rate.

Onlay versus inlay humeral components in reverse shoulder arthroplasty: A systematic review and meta-analysis

Background Advances have been made to the traditional inlay Grammont Reverse Shoulder Arthroplasty (RSA) design such as the onlay humeral component prosthesis. Currently, there is no agreement in the literature regarding the best option for the humeral component when comparing inlay and onlay designs. This review compares the outcomes and complications between onlay versus inlay humeral components for RSA. Methods A literature search was conducted using PubMed and Embase. Only studies reporting outcomes comparing onlay versus inlay RSA humeral components were included. Results Four studies with 298 patients (306 shoulders) were included. Onlay humeral components were associated with better external rotation (ER) ( p < 0.0001). No significant difference in forward flexion (FF) or abduction was found. Constant scores (CS) and VAS scores did not differ. Increased scapular notching was found in the inlay group (23.18%) versus the onlay group (7.74%) ( p = 0.02). Postoperative scapular fractures and acromial fractures did not differ. Conclusion Onlay and inlay RSA designs are associated with improved postoperative range of motion (ROM). Onlay humeral designs may be associated with greater ER and lower rate of scapular notching; however, no difference was found in Constant and VAS scores, so further studies are required to assess the clinical significance of these differences.

Associations between radiographic parameters in the reverse shoulder arthroplasty and patient outcomes

Background Various radiological parameters have been measured in the Reverse Shoulder Arthroplasty (RSA) and correlated to patient outcomes, to determine best baseplate position. Results remain unclear with respect to certain parameters such as inferior baseplate tilt. We have investigated our series of patients to clarify the relationship between radiological parameters and patient outcomes. Methods We conducted a UK based bi-centre retrospective review of 156 prostheses. Critical shoulder angle (CSA), RSA angle (RSAA), Overhang and Deltoid Lever Arm (DLA) were measured on preoperative and postoperative radiographs. Range of motion and Oxford Shoulder Score (OSS) (range 1–8 years) were obtained. We assessed for scapular notching at minimum 1 year follow up (n = 138). Results Decreased postoperative CSA and increased DLA were associated with higher OSSs (P = 0.001 and 0.019). Increased overhang and DLA were associated with increased flexion (P = 0.033 and 0.024 respectively). Multivariate analysis showed that CSA and DLA affected notching rate (P = 0.002 and 0.007). Conclusions Baseplate tilt in relation to the acromion (CSA) and DLA are the most predictive parameters for notching and OSS. We recommend considering a maximum CSA of 26 degrees to decrease notching rate and improve OSS. We recommend considering an Overhang of at least 6 mm to improve FF.

Is limited external rotation after reverse shoulder arthroplasty associated with glenoidal notching?

Background Reverse shoulder arthroplasty (RSA) is a valuable solution for patients with shoulder pain or injury primarily due to a rotator cuff tear or secondary to traumatic events. Nevertheless, several complications are known to appear, with the most frequent being scapular notching (SN) on the inferior and posterior scapular neck. Controversial data exist about the clinical relevance of SN. Since further consequences are still not clearly understood, we aimed to provide more clarity on which factors, especially external rotation (ER), contribute to the appearance and progress of notching. Methods Constant Score (CS), Subjective Shoulder Value (SSV), flexion, abduction, and ER were evaluated retrospectively in 153 shoulders of 147 patients (mean age 79±7.7 years; 62% women) who underwent RSA between 2005 and 2010. Anteroposterior radiographs were evaluated before and 1, 2, 3, and 5 years after RSA for SN according to the Sirveaux classification. The evaluation was performed by two independent surgeons. Spearman’s coefficient and t-test were used. Results CS, SSV, flexion, and abduction increased significantly 1 year after RSA compared to before (all p < 0.0001). No improvement was shown for ER between the same timepoints. Between 2 and 5 years of follow-up, only flexion decreased by 5°(p = 0.02) while CS, SSV, abduction, and ER remained constant. After RSA, notching increases over time. There was no association between SN and CS, SSV, flexion, abduction or ER at any of the measured timepoints. Higher flexion correlated with higher abduction after RSA at every follow-up (1 year r = 0.88, 2 years r = 0.89, 3 years r = 0.86, 5 years r = 0.86). The interrater correlation test showed a strong correlation (r = 0.7). Conclusion We verified the functional benefits of RSA for patients. Additionally, our findings show that despite radiographic progression of notching and unchanged limited ER, the postoperative improvements in CS, SSV, flexion, and abduction are preserved over 5 years.

Mechanical complications and fractures after reverse shoulder arthroplasty related to different design types and their rates: part I

The initial reverse shoulder arthroplasty (RSA), designed by Paul Grammont, was intended to treat rotator cuff tear arthropathy in elderly patients. In the early experience, high complication rates (up to 24%) and revision rates (up to 50%) were reported. The most common complications reported were scapular notching, whereas clinically more relevant complications such as instability and acromial fractures were less commonly described. Zumstein et al defined a ‘complication’ following RSA as any intraoperative or postoperative event that was likely to have a negative influence on the patient’s final outcome. High rates of complications related to the Grammont RSA design led to development of non-Grammont designs, with 135 or 145 degrees of humeral inclination, multiple options for glenosphere size and eccentricity, improved baseplate fixation which facilitated glenoid-sided lateralization, and the option of humeral-sided lateralization. Improved implant characteristics combined with surgeon experience led to a dramatic fall in the majority of complications. However, we still lack a suitable solution for several complications, such as acromial stress fracture. Cite this article: EFORT Open Rev 2021;6:1097-1108. DOI: 10.1302/2058-5241.6.210039

Reverse shoulder arthroplasty in complex fractures of the proximal humerus: results after 7 years of follow-up

Background There is still little information about the long-term results of clinical and radiological evolution in patients older than 65 years with complex proximal humerus fractures (CPHF) treated acutely with reverse shoulder arthroplasty (RSA). The aim of this paper was to evaluate function and results 7 years after surgery. Material and methods A prospective cross-sectional cohort study was designed for this purpose. Patients who underwent RSA surgery during 2012 because of a CPHF were included. The surgical approach was randomized (deltopectoral vs anterosuperior). Functional activity, evolution of tuberosities and evidence of scapular notching 7 years after surgery were analyzed. Results After evaluating 32 patients, the Constant score improved from 64.83 in the first year to 69.54 at 7 years postoperative. Results were independent of the approach used. Functional outcomes were poorer in patients with scapular notching and when tuberosities were resorbed or displaced. Conclusions At 7 years, function in patients undergoing RSA after CPHF demonstrated improvement in all patients except those who developed scapular notching or when tuberosities did not consolidate in an anatomical position. These results are completely independent of the approach used. Level of evidence III Controlled cohort study.

Mid-term outcomes of bony increased offset-reverse total shoulder arthroplasty in the Asian population

Background: To evaluate clinical and radiological outcomes of bony increased offset-reverse total shoulder arthroplasty (BIO-RSA) in the Asian population at mid-term follow-up.Methods: From June 2012 to August 2017 at a single center, 43 patients underwent BIO-RSA, and 38 patients with a minimum of 2 years of follow-up were enrolled. We evaluated the preoperative and postoperative clinical outcomes, radiological outcomes (notching and loosening), and complications of BIO-RSA at the last follow-up. In addition, we divided these patients into notching and not-notching groups and compared the demographics, preoperative, and postoperative characteristics of patients between the two groups.Results: Visual analog scale, American Shoulder and Elbow Surgeons, University of California-Los Angeles, and Simple Shoulder Test scores improved significantly from preoperative (average: 5, 39.43, 16.22, 3.94) to postoperative (average: 1.71, 78.91, 28.34, 7.8; p<0.05) outcomes. All range of motion except internal rotation improved significantly at the final follow-up (p<0.05), and the bone graft was well-incorporated with the native glenoid in all patients (100%). However, scapular notching was observed in 20/38 patients (53%). In the comparison between notching and not-notching groups (18 vs. 20 patients), there were no significant differences in demographics, radiological parameters, and clinical outcomes except acromion-greater tuberosity (AT) distance (p=0.003). Intraoperative complications were three metaphyseal fractures and one inferior screw malposition. Postoperative complications included one heterotopic ossification, one scapula neck stress fracture, one humeral stem loosening, and one late infection.Conclusions: BIO-RSA resulted in improved clinical outcomes at mid-term follow-up in the Asian population. Although better cosmesis and advantages of glenoid lateralization were observed, we observed higher rates of scapular notching compared to previously reported rates in BIO-RSA studies. In addition, adequate glenoid lateralization with appropriate humeral lengthening (AT distance) might reduce scapular notching.

Reverse shoulder arthroplasty-early results

Although reverse shoulder arthroplasty is used in massive rotator cuff tears, it is also used in proximal humerus fractures and shoulder arthroplasty revision. In this study, we aimed to examine the early radiological and clinical results of patients undergoing reverse shoulder arthroplasty with different diagnoses. Between 2010 and 2013, reverse shoulder arthroplasty was applied to 10 patients (4 men, 6 women) with the diagnosis of arthropathy due to rotator cuff tear (n: 7), multi-fragmentary proximal humerus fracture (n: 2) and hemiarthroplasty revision (n: 1). The median age of the patients was 74 (64-85) years and the median follow-up was 15.5 (3-35) months. Patients were assessed in terms of joint range of motion, Constant score and Visual Pain Scale (VAS) and radiological examinations before and after surgery. Preoperative active shoulder flexion, abduction, internal and external rotation degrees of the patients were 65, 30, 40 and 50 degrees, and 105, 95, 30, 57.5 degrees respectively in their final controls. Constant score was 20.5 (14-63) preoperatively, and 54.5 (38-64) in the final controls (p˂0.05). While the preoperative VAS was 7 (3-9), it was found to be 1.5 (1-3) in the final controls (p˂0.05). As a complication, scapular notching was observed in one patient. Internal external rotation values were better in the rotator cuff arthropathy group than the fracture group. Reverse shoulder arthroplasty, especially in the treatment of patients with rotator cuff arthropathy, has good early results and a low complication rate. We recommend paying attention to the glenoid component location to avoid scapular notching.