Subscapularis- and deltoid-sparing vs traditional deltopectoral approach in reverse shoulder arthroplasty: a prospective case-control study

Retrospective analysis of the subscapularis-sparing approach for reverse total shoulder arthroplasty

PURPOSE

The influence of the subscapularis tendon on reverse total shoulder arthroplasty (RTSA) has been discussed controversially. The aim of the study was to investigate the subscapularis-sparing approach for RTSA and the effect of the intact subscapularis tendon.

METHODS

This retrospective comparative study included 93 patients. Among these, 55 underwent the deltopectoral subscapularis-sparing approach, and in 38 cases, the standard deltopectoral approach with subscapularis tenotomy was applied. At the final follow-up, representative shoulder scores were measured, radiographs were taken in two planes, and shoulder sonography was performed.

RESULTS

The subscapularis-sparing group showed a significantly higher Constant score (71.8 vs. 65.9 points) and adapted Constant score if the subscapularis tendon was shown to be intact in the postoperative sonography (85.2% vs. 78.6%) (p = 0.005; p = 0.041). Furthermore, these patients had improved abduction (128.2 vs. 116.8, p = 0.009) and external rotation (34.6 vs. 27.1, p = 0.047). However, no significant differences were found for the degree of internal rotation and internal rotation strength. No dislocation or infection was observed. The degree of scapular notching was not significantly different between the two groups (p = 0.082). However, independently from the integrity of the subscapularis the subscapularis-sparing approach showed no difference in clinical and radiographic outcome (Constant score scapularis-sparing 70.0 points vs. tenotomy 66.8 points; p = 0.27).

CONCLUSION

The subscapularis-sparing approach RTSA showed improved clinical outcome, abduction, and external rotation, if the subscapularis was shown to be intact at time of follow-up. Both groups showed no difference in internal rotation.

The effect of subscapularis repair in reverse total shoulder arthroplasty depends on the design of the implant: a comparative study with a minimum 2-year follow-up

INTRODUCTION

The role of the subscapularis (Ssc) tendon does not yet have a well-defined role in RSA. The purpose of the present study was to evaluate if the repair of the Ssc in RSA improves overall clinical and radiographic results and if it has the same results using a medialized design humeral stem compared to a lateralized design.

METHODS

Eighty-four consecutive patients undergoing RSA were retrospectively analyzed. Nine patients were lost at FU. Two implants with similar glenosphere design and different stem design (medialized and lateralized) were used. The Ssc was repaired in case of good quality of the fibers and reducibility without tension intraoperatively. Patients were divided into four groups for data analysis depending on whether they had received a medialized or lateralized design and Ssc repair or not. Patients were reviewed at an average follow-up of 40.8 ± 13.1 months. Clinical outcome measures included Active range of motion (ROM), strength, visual analog scale (VAS), Constant-Murley score (CMS), and the American Shoulder and Elbow Surgeons score (ASES). Radiographic evaluation at final follow-up was performed to assess scapular notching, stress shielding, and radiolucent lines.

RESULTS

No statistically significant clinical differences (p > 0.05) emerged between Lat/Ssc+ and Lat/Ssc-. Conversely, the patients belonging to the Med/Ssc- group reported statistically worse (p < 0.05) results than the Med/Ssc + group in terms of VAS, ASES and CMS. Statistically worse (p < .05) results in the Med/Ssc- group than in the Med/Ssc + were found also in active ROM achieved in FE, ABD, ER1 and ER2, and in the strength obtained in FE, ABD and ER2. Scapular notching was reported in 3 shoulders (15.7%) in Lat/Ssc+ group and in 7 shoulders (50%) in Lat/Ssc- group, while it was reported in 4 shoulders (14.2%) in Med/Ssc + group and in 6 shoulders (42.8%) in Med/Ssc- group. Stress shielding was observed in 6 cases in Lat/Ssc+ group (31.6%), in 8 cases in Lat/Ssc- group (57.1%), in 3 cases (10.7%) in Med/Ssc + group and 4 cases in Med/Ssc- group (28.6%).

CONCLUSIONS

Patients undergoing RSA show clinical improvements at mid-term follow-up with a low rate of complications, regardless of the use of a medialized or a lateralized humeral stem design. Ssc repair is associated with better functional outcomes in the cohort of medialized stem, while it did not yield significant differences in the cohort of lateralized stem.

LEVEL OF EVIDENCE

Level III; Retrospective Cohort Comparison; Treatment Study.

Subscapularis repair for reverse shoulder arthroplasty: a systematic review and meta-analysis

BACKGROUND

The purpose of this study is to perform a systematic review of the literature evaluating the importance of subscapularis repair in patients who underwent reverse shoulder arthroplasty (RSA).

METHODS

A systematic search of articles in PubMed, EMBASE, and the Cochrane Library databases was carried out according to the PRISMA guidelines. Cohort studies comparing RSA with subscapularis repair vs. RSA without subscapularis repair were included. All statistical analysis was performed using Review Manager. A P value of <.05 was considered to be statistically significant.

RESULTS

Seventeen studies with 2620 patients were included. Subscapularis repair resulted in less instability compared to without subscapularis repair (0.8% vs. 4.2%, P = .04), and there were no significant differences in rate of instability with lateralization (0.6% vs. 1.6%, P = .40), revision rates (2.6% vs. 3.9%, P = .62), and complication rates (7.7% vs. 4.9%, P = .21). Subscapularis repair had improved American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) scores (83.6 vs. 80.2, P = .02) and Constant scores (72.6 vs. 68.9, P < .01) but there was not a significant difference in visual analog scale pain scores (1.2 vs. 1.6, P = .11). Subscapularis repair had a significant difference in forward flexion (140° vs. 137°, P = .04) and internal rotation score (5.5 vs. 4.6, P = .001); however, there was no significant difference in external rotation (35° vs. 35°, P = .80) and abduction (117° vs. 123°, P = .13).

CONCLUSION

This study found that RSA with subscapularis repair demonstrated a reduction in the occurrence of implant instability with medialized implants. However, subscapularis repair did not yield improvements in revision rates, complications, or instability with lateralized implants. Additionally, other outcome measures such as ASES, Constant score, and range of motion exhibited statistically significant improvements with subscapularis repair but did not surpass clinically significant thresholds.

Subscapular sparing approach for total shoulder arthroplasty: a systematic review and meta-analysis of comparative studies

Background

Total shoulder arthroplasty has been effective in treating primary glenohumeral arthritis surgically. However, the subscapularis (SSC) tendon must be released as part of the surgery's conventional approach, which could lead to postoperative problems and later tendon failure. Using a procedure that spares the tendon, Lafosse et al reported improved postoperative SSC performance. This meta-analysis will compare this approach to the standard one.

Methods

PubMed, Cochrane, and Google Scholar (pages 1-20) were searched till October 2022. The clinical outcomes consisted of the postoperative pain, adverse events, and range of motion.

Results

Only 3 studies were included in this meta-analysis. The subscapularis sparing approach tended to have better postoperative internal rotation (P = .06) and shoulder elevation (P = .1); however, the results were marginally statistically insignificant.

Conclusion

This is the first meta-analysis to compare the subscapularis sparing to the standard approach in total shoulder arthroplasty. Showing better postoperative range of motion (elevation and internal rotation), the SSC approach might be considered as a good substitute to the standard one. However, it is limited by the potentially limited exposure making it harder to use in muscular and obese patients. More randomized clinical trials are needed to reach more significant results and establish clearer indications of this approach.

Shoulder Surgery Postoperative Immobilization: An International Survey of Shoulder Surgeons

BACKGROUND

There is currently no consensus on immobilization protocols following shoulder surgery. The aim of this study was to establish patterns and types of sling use for various surgical procedures in the United States (US) and Europe, and to identify factors associated with the variations.

METHODS

An online survey was sent to all members of the American Shoulder and Elbow Society (ASES) and European Society for Surgery of the Shoulder and Elbow (ESSSE). The survey gathered member data, including practice location and years in practice. It also obtained preferences for the type and duration of sling use after the following surgical procedures: arthroscopic Bankart repair, Latarjet, arthroscopic superior/posterosuperior rotator cuff repair (ARCR) of tears <3 cm and >3 cm, anatomic total shoulder arthroplasty (aTSA) and reverse TSA (rTSA), and isolated biceps tenodesis (BT). Relationships between physician location and sling type for each procedure were analyzed using Fisher's exact tests and post-hoc tests using Bonferroni-adjusted p-values. Relationships looking at years in practice and sling duration preferred were analyzed using Spearman's correlation tests.

RESULTS

In total, 499 surgeons with a median of 15 years of experience (IQR = 9-25) responded, with 54.7% from the US and 45.3% from Europe. US respondents reported higher abduction pillow sling use than European respondents for the following: Bankart repair (62% vs. 15%, p < 0.0001), Latarjet (53% vs. 12%, p < 0.001), ARCR < 3 cm (80% vs. 42%, p < 0.001) and >3 cm (84% vs. 61%, p < 0.001), aTSA (50% vs. 21%, p < 0.001) and rTSA with subscapularis repair (61% vs. 22%, p < 0.001) and without subscapularis repair (57% vs. 17%, p < 0.001), and isolated BT (18% vs. 7%, p = 0.006). European respondents reported higher simple sling use than US respondents for the following: Bankart repair (74% vs. 31%, p < 0.001), Latarjet (78% vs. 44%, p < 0.001), ARCR < 3 cm (50% vs. 17%, p < 0.001) and >3 cm (34% vs. 13%, p < 0.001), and aTSA (69% vs. 41%, p < 0.001) and rTSA with subscapularis repair (70% vs. 35%, p < 0.001) and without subscapularis repair (73% vs. 39%, p < 0.001). Increasing years of experience demonstrated a negative correlation with the duration of sling use after Bankart repair (r = -0.20, p < 0.001), Latarjet (r = -0.25, p < 0.001), ARCR < 3 cm (r = -0.14, p = 0.014) and >3 cm (r = -0.20, p < 0.002), and aTSA (r = -0.37, p < 0.001), and rTSA with subscapularis repair (r = -0.10, p = 0.049) and without subscapularis repair (r = -0.19, p = 0.022. Thus, the more experienced surgeons tended to recommend shorter durations of post-operative sling use. US surgeons reported longer post-operative sling durations for Bankart repair (4.8 vs. 4.1 weeks, p < 0.001), Latarjet (4.6 vs. 3.6 weeks, p < 0.001), ARCR < 3 cm (5.2 vs. 4.5 weeks p < 0.001) and >3 cm (5.9 vs. 5.1 weeks, p < 0.001), aTSA (4.9 vs. 4.3 weeks, p < 0.001), rTSR without subscapularis repair (4.0 vs. 3.6 weeks, p = 0.031), and isolated BT (3.7 vs. 3.3 weeks, p = 0.012) than Europe respondents. No significant differences between regions within the US and Europe were demonstrated.

CONCLUSIONS

There is considerable variation in the immobilization advocated by surgeons, with geographic location and years of clinical experience influencing patterns of sling use. Future work is required to establish the most clinically beneficial protocols for immobilization following shoulder surgery.

LEVEL OF EVIDENCE

Level IV.

Results after primary reverse shoulder arthroplasty with and without subscapularis repair: a prospective-randomized trial

INTRODUCTION

Indications for reverse shoulder arthroplasties (rTSA) have increased since their development by Paul Grammont in 1985. Prosthesis design was enhanced over time, but the management of the tendon of the M. subscapularis (SSC-tendon) in primary rTSA is still a controversial subject with regard to perform a refixation or not.

METHODS

50 patients were randomized in a refixation group (A) and a non-refixation-group (B) of the SSC-tendon in a double-blinded fashion. SSC-function was assessed at baseline before surgery, such as 3 and 12 months after surgery. Constant-Murley-Shoulder Score (CS), American Shoulder and Elbow Surgeons Score (ASES), strength, range of motion (ROM), and pain on numeric rating scale (NRS) were measured in all examinations. An ultrasound examination of the shoulder was performed for evaluation of subscapularis tendon integrity at 3 and 12 month follow-up visits. Pain was evaluated on NRS via phone 5 days after surgery. Surgery was performed by a single experienced senior surgeon in all patients.

RESULTS

Patients with a refixation of the SSC-tendon and primary rTSA had improved internal rotation [40° (20°-60°) vs. 32° (20°-45°); p = 0.03] at 12 months of follow-up. Additionally, the A-group had increased CS [74 (13-90) vs. 69.5 (40-79); p = 0.029] 1 year after surgery. Results were strengthened by subgroup analysis of successful refixation in ultrasound examination vs. no refixation. No differences were seen in ASES and NRS 1 year after rTSA.

CONCLUSION

SSC-tendon repair in rTSA improves CS and internal rotation 12 months after surgery.

Anterosuperior approach versus deltopectoral approach for reverse total shoulder arthroplasty: a systematic review and meta-analysis

BACKGROUND

Surgical approach is an important factor that may affect the outcomes of reverse total shoulder arthroplasty (RTSA). The most common approaches for RTSA are anterosuperior (AS) and deltopectoral (DP). However, controversy exists on which surgical approach is better. This meta-analysis aimed to compare both approaches in terms of radiological and clinical outcomes and complications.

METHODS

We searched PubMed, Embase, and Cochrane Library databases for studies that compared the postoperative outcomes of the AS and DP approaches for RTSA. After screening and quality assessment of the articles, we obtained two randomized controlled trials and four retrospective comparative studies. We analyzed the radiologic outcomes, functional outcomes, and complications between the two approaches. The standardized mean difference and odds ratio were used to analyze the differences in outcomes between the two surgical approaches. Statistical significance was set at P < 0.05.

RESULTS

The incidence rate of glenoid implant loosening was significantly (P = 0.04) lower in the AS group than that in the DP group. In terms of forward flexion after surgery, the DP approach produced significantly (P = 0.03) better outcomes compared with the AS approach. There were no significant differences in radiological outcomes or other complication rates between the two approaches.

CONCLUSION

As a result of this meta-analysis, one of the two approaches did not bring a better result than the other. One has strength for better forward flexion and the other for a lower glenoid loosening rate. With this in mind, it is recommended to use the approach that the surgeon is most familiar with.

The role of subscapularis repair following reverse shoulder arthroplasty: systematic review and meta-analysis

PURPOSE

Inadequate subscapularis repair has been advocated as one of the contributing factors for dislocation in reverse total shoulder arthroplasty; nonetheless the need to restore the subscapularis tendon integrity is under debate. The aim of this systematic review was to answer the question: does subscapularis reattachment following reverse total shoulder arthroplasty improve joint stability, range of motion and functional scores?

METHODS

The literature was systematically screened in accordance with PRISMA guidelines looking for papers evaluating clinical outcomes of reverse total shoulder arthroplasty in relation to the management of subscapularis tendon. Studies comparing clinical outcomes, complications and dislocation rate with or without subscapularis repair were included. Studies in which reverse total shoulder arthroplasty was performed for trauma or tumors were excluded. The methodology of included articles was scored with MINORS scale and the Risk of Bias was assessed adopting the ROBINS-I (Risk Of Bias In Non-randomized Studies of Interventions) developed by the Cochrane Group. A meta-analysis was also performed combining the studies to increase the sample size and hence the power to obtain meaningful data.

RESULTS

The database search identified 1062 records, and 6 full-text articles were finally included. A total number of 1085 reverse total shoulder arthroplasty were assessed on. Except for one study, lateralized prosthetic designs have been used. Dislocation occurred in 0.8% (5/599 patients) of the patient with repaired subscapularis and in 1.6% (8/486 patients) of the tenotomized patients, and subscapularis repair was not associated with a higher risk of dislocation (pooled Peto OR: 0.496, 95% CI: 0.163 to 1.510, p = 0.217). Qualitative assessment revealed no differences in the range of motion and clinical scores.

CONCLUSION

Subscapularis repair after reverse total shoulder arthroplasty produces no clinically meaningful benefits, particularly using lateralized prosthetic designs. Subscapularis re-attachment does not improve implant stability, nor increases range of motion or clinical scores. Given these results, keeping in mind the antagonistic effect of the repaired subscapularis on external rotation, no evidence lead to suggest subscapularis reattachment following reverse total shoulder arthroplasty with lateralized prosthetic designs.

Measuring Patient Value after Total Shoulder Arthroplasty

Evaluating the value of health care is of paramount importance to keep improving patients' quality of life and optimizing associated costs. Our objective was to present a calculation method based on Michael Porter's formula and standard references to estimate patient value delivered by total shoulder arthroplasty (TSA). We retrospectively reviewed the records of 116 consecutive TSAs performed between June 2015 and June 2019. Patient value was defined as quality of care divided by direct costs of surgery. Quality metrics included intra- and postoperative complications as well as weighted improvements in three different patient-reported outcome measures at a minimum of one-year follow-up. Direct costs of surgery were retrieved from the management accounting analyses. Substantial clinical benefit (SCB) thresholds and the standard reimbursement system were used as references for quality and cost dimensions. A multivariable linear regression was performed to identify factors associated with patient delivered value. Compared to a reference of 1.0, the quality of care delivered to patients was 1.3 ± 0.3 (range, 0.6-2.0) and the associated direct cost was 1.0 ± 0.2 (range, 0.7-1.6). Ninety patients (78%) had a quality of care ≥1.0 and 61 patients (53%) had direct costs related to surgery ≤1.0. The average value delivered to patients was 1.3 ± 0.4 (range, 0.5-2.5) with 91 patients (78%) ≥ 1.0, was higher for non-smokers (beta, 0.12; p = 0.044), anatomic TSA (beta, 0.53; p < 0.001), increased with higher pre-operative pain (beta, 0.08; p < 0.001) and lower pre-operative Constant score (beta, -0.06; p = 0.001). Our results revealed that almost 80% of TSAs provided substantial patient value. Patient pre-operative pain/function, tobacco use, and procedure type are important factors associated with delivered patient value.

Problems, complications, and reinterventions in 4893 onlay humeral lateralized reverse shoulder arthroplasties, a systematic review: part II-problems and reinterventions

BACKGROUND

Several modifications to the original Grammont reverse shoulder arthroplasty (RSA) design have been proposed to prevent distinctive issues, such as both glenoid and humeral lateralization. The aim of this systematic review was to determine rates of problems, complications, reoperations, and revisions after onlay lateralized humeral stem RSA, hypothesizing that these are design related.

METHODS

This systematic review was performed in accordance with the PRISMA statement guidelines. A literature search was conducted (1 January 2000 to 14 April 2020) using PubMed, Cochrane Reviews, Scopus, and Google Scholar, employing several combinations of keywords: "reverse shoulder arthroplasty," "reverse shoulder prosthesis," "inverse shoulder arthroplasty," "inverse shoulder prosthesis," "problems," "complications," "results," "outcomes," "reoperation," and "revision."

RESULTS

Thirty-one studies with 4893 RSA met inclusion criteria. The 892 postoperative problems and 296 postoperative complications represented overall problem and complication rates of 22.7% and 7.5%, respectively. Forty-one reoperations and 63 revisions resulted, with overall reoperation and revision rates of 1.7% and 2.6%, respectively.

CONCLUSIONS

Problem, complication, and reintervention rates proved acceptable when implanting a high humeral lateralization stem RSA. The most frequent problem was scapular notching (12.6%), and the most common postoperative complication was scapular stress fracture (1.8%). An overall humeral complication rate of 1.9% was identified, whereas no humeral fractures or stem loosening were reported with short stems. Infections (1.3%) were the most common reason for component revision, followed by instability (0.8%).

LEVEL OF EVIDENCE

Systematic review IV.

Radiological changes, infections and neurological complications after reverse shoulder arthroplasty related to different design types and their rates: Part II

Early reported complication rates with the Grammont-type reverse shoulder arthroplasty (RSA) were very high, up to 24%.A 'problem' is defined as an intraoperative or postoperative event that is not likely to affect the patient's final outcome, such as intraoperative cement extravasation and radiographic changes. A 'complication' is defined as an intraoperative or postoperative event that is likely to affect the patient's final outcome, including infection, neurologic injury and intrathoracic central glenoid screw placement.Radiographic changes around the glenoid or humeral components of the RSA are very frequently observed and described in the literature.High complication rates related to the Grammont RSA design led to development of non-Grammont designs which led to a dramatic fall in the majority of complications.The percentage of radiological changes after RSA is not negligible and remains unsolved, despite a decrease in its occurrence in the last decade. However, such changes should be now considered as simple problems because they rarely have a negative influence on the patient's final outcome, and their prevalence has dramatically decreased.With further changes in indications and designs for RSA, it is crucial to accurately track the rates and types of complications to justify its new designs and increased indications. Cite this article: EFORT Open Rev 2021;6:1109-1121. DOI: 10.1302/2058-5241.6.210040.

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.

Problems, complications, and reinterventions in 4893 onlay humeral lateralized reverse shoulder arthroplasties: a systematic review (part I-complications)

Background

Several modifications to the original Grammont reverse shoulder arthroplasty (RSA) design have been proposed to prevent distinctive issues, such as both glenoid and humeral lateralization. The aim of this systematic review was to determine rates of problems, complications, reoperations, and revisions after onlay lateralized humeral stem RSA, hypothesizing that these are design related.

Methods

This systematic review was performed in accordance with the PRISMA statement guidelines. A literature search was conducted (01.01.2000–14.04.2020) using PubMed, Cochrane Reviews, Scopus, and Google Scholar employing several combinations of keywords: “reverse shoulder arthroplasty,” “reverse shoulder prosthesis,” “inverse shoulder arthroplasty,” “inverse shoulder prosthesis,” “problems,” “complications,” “results,” “outcomes,” “reoperation,” “revision.”

Results

Thirty-one studies with 4893 RSA met inclusion criteria. The 892 postoperative problems and 296 postoperative complications represented overall problem and complication rates of 22.7% and 7.5%, respectively. Forty-one reoperations and 63 revisions resulted, with an overall reoperation rate of 1.7% and overall revision rate of 2.6%.

Conclusions

Problem, complication, and reintervention rates proved acceptable when implanting a high humeral lateralization stem in RSA. The most frequent problem was scapular notching (12.6%), and the most common postoperative complication was scapular stress fracture (1.8%). An overall humeral complication rate of 1.9% was identified, whereas short stems reported no humeral fractures or stem loosening. Infections (1.3%) proved to be the most common reason for component revision, and instability had a complication rate of 0.8%.

Level of evidence

Systematic review IV

Subscapularis-sparing approaches in shoulder arthroplasty: A systematic review

Background

Novel approaches for anatomic and reverse total shoulder arthroplasty (aTSA and rTSA) that spare the subscapularis (SSC) have recently been described. Outcomes for the SSC-sparing approach were evaluated through this systematic review.

Methods

Medline, Embase, PubMed, and CENTRAL were searched.

Results

From 2051 citations, 8 studies were included (aTSA group, n = 241; rTSA group, n = 68). SSC-sparing aTSA and rTSA were associated with significant postoperative improvements in shoulder function and range of motion at 12- to 24-month follow-up.

Conclusion

The SSC-sparing approach may provide a safe alternative for up to two years post-surgery. Evidence for long-term use remains inconclusive.

The modern reverse shoulder arthroplasty and an updated systematic review for each complication: part II

Background

Globally, reverse shoulder arthroplasty (RSA) has moved away from the Grammont design to modern prosthesis designs. The purpose of this study was to provide a focused, updated systematic review for each of the most common complications of RSA by limiting each search to publications after 2010. In this part II, the following were examined: (1) instability, (2) humerus/glenoid fracture, (3) acromial/scapular spine fractures (AF/SSF), and (4) problems/miscellaneous.

Methods

Four separate PubMed database searches were performed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Overall, 137 studies for instability, 94 for humerus/glenoid fracture, 120 for AF/SSF, and 74 for problems/miscellaneous were included in each review, respectively. Univariate analysis was performed with chi-square and Fisher exact tests.

Results

The Grammont design had a higher instability rate vs. all other designs combined (4.0%, 1.3%; P < .001), and the onlay humerus design had a lower rate than the lateralized glenoid design (0.9%, 2.0%; P = .02). The rate for intraoperative humerus fracture was 1.8%; intraoperative glenoid fracture, 0.3%; postoperative humerus fracture, 1.2%; and postoperative glenoid fracture, 0.1%. The rate of AF/SSF was 2.6% (371/14235). The rate for complex regional pain syndrome was 0.4%; deltoid injury, 0.1%; hematoma, 0.3%; and heterotopic ossification, 0.8%.

Conclusions

Focused systematic reviews of recent literature with a large volume of shoulders demonstrate that using non-Grammont modern prosthesis designs, complications including instability, intraoperative humerus and glenoid fractures, and hematoma are significantly reduced compared with previous studies. As the indications continue to expand for RSA, it is imperative to accurately track the rate and types of complications in order to justify its cost and increased indications.

Do short stems influence the cervico-diaphyseal angle and the medullary filling after reverse shoulder arthroplasties?

BACKGROUND

Shorter humeral stems were developed to improve bone preservation, vascularity and osteointegration in reverse total shoulder arthroplasty (RSA). While some studies examined the relationship between canal filling and radiographic changes, none evaluated the association between stem alignment and canal fill ratio (CFR).

HYPOTHESIS

The hypothesis was that stem misalignment after RSA would be associated with lower CFR.

PATIENTS AND METHODS

The authors retrospectively reviewed immediate postoperative radiographs of 157 patients, comprising 56 men (36%), who underwent RSA with a short uncemented stem with neck shaft angle (NSA) default of 145°. The parameters included postoperative NSA and metaphyseal CFR, both measured with excellent inter-observer agreement. Uni- and multivariable linear regressions were performed to determine associations between postoperative NSA and 5 variables (CFR, gender, age, BMI, and surgical approach).

RESULTS

Postoperative NSA was 149°±8°, exceeding 5° of varus in 15 shoulders (9%) and 5° of valgus in 60 shoulders (38%), and CFR was 58%±8%. CFR was lower in shoulders with varus stem alignment (54%±6%) than shoulders with neutral stem alignment (59%±8%, p=0.033). Multivariable regression revealed that postoperative NSA increased with age (beta: 0.20; p=0.008), was higher for shoulders operated with the subscapularis- and deltoid-sparing approach (beta: 3.82; p=0.040) but lower for men (beta: -4.14; p=0.002).

CONCLUSIONS

Stem misalignment exceeded 5° in 47% of the shoulders. Women, older age, and subscapularis- and deltoid-sparing approach are associated with greater risks of valgus stem positioning, while lower CFR seems to be associated with greater risks of varus stem positioning.

LEVEL OF EVIDENCE

IV; case series.

The over-the-top subscapularis repair in reverse shoulder arthroplasty: biomechanical evaluation of a novel technique

Background

We evaluate the effect of repairing the upper subscapularis tendon at an alternative location on the anterior greater tuberosity above the center of rotation using a reverse shoulder arthroplasty (RSA) muscle model.

Methods

We compared an innovative subscapularis repair on the anterior aspect of the greater tuberosity with the standard repair on the lesser tuberosity in a previously validated digital linear RSA muscle model. Standard repair vs. a new repair datasets were compared for 3 RSA designs. Each model was run through humeral abduction from 0° to 140° in 2.5° increments; the resulting moment arm measurements (model of tendon efficiency) were recorded in millimeters for 3 sections (superior, middle, inferior). An isolated upper two-thirds subscapularis repair to the anterior greater tuberosity was also evaluated (the over-the-top repair).

Results

The new over-the-top subscapularis repair significantly increased the abduction moment arm lengths in the superior, middle, and inferior subscapularis components compared with the standard repair to the lesser tuberosity at all levels of glenohumeral abduction and for all 3 RSA designs. Repair of the upper two-thirds of the subscapularis to the new location was an abductor at a much lower level of abduction compared with the native subscapularis repair.

Conclusion

By repairing the upper subscapularis tendon above the center of rotation (over-the-top repair) in an RSA muscle model, the subscapularis has an improved movement arm and functions as an abductor through a greater range of motion that may result in clinically increased muscle efficiency and improved strength.

How common are acromial and scapular spine fractures after reverse shoulder arthroplasty?: A systematic review

AIMS

Acromial fractures following reverse shoulder arthroplasty (RSA) have a wide range of incidences in reported case series. This study evaluates their incidence following RSA by systematically reviewing the current literature.

MATERIALS AND METHODS

A systematic review using the search terms "reverse shoulder", "reverse total shoulder", or "inverted shoulder" was performed using PubMed, Web of Science, and Cochrane databases between 1 January 2010 and 31 March 2018. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used. Studies were included if they reported on RSA outcomes and the incidence rate of acromial and/or scapular spine fractures. The rate of these fractures was evaluated for primary RSA, revision RSA, RSA indications, and RSA implant design.

RESULTS

The review included 90 articles out of 686 identified after exclusions. The incidence rate of acromial and/or scapular spine fractures was 2.8% (253/9048 RSAs). The fracture rate was similar for primary and revision RSA (2.8% vs 2.1%; p = 0.4). Acromial fractures were most common after RSA for inflammatory arthritis (10.9%) and massive rotator cuff tears (3.8%). The incidence was lowest in RSA for post-traumatic arthritis (2.1%) and acute proximal humerus fractures (0%). Lateralized glenosphere design had a significantly higher rate of acromial fractures compared with medial glenosphere designs.

CONCLUSION

Based on current English literature, acromial and/or scapular spine fractures occur at a rate of 2.8% after RSA. The incidence is slightly more common after primary compared with revision arthroplasty. Also, higher rates of acromial fractures are reported in RSA performed for inflammatory arthritis and in the lateralized glenoid design. Cite this article: Bone Joint J 2019;101-B:627-634.

Subscapularis in Reverse Total Shoulder Arthroplasty

The use of reverse total shoulder arthroplasty (RSA) is becoming increasingly popular, but many biomechanical aspects are poorly understood. Particularly, the role and function of the subscapularis following RSA are unclear. Several clinical and biomechanical studies have analyzed its role in range of motion and stability. There is some evidence that the subscapularis is beneficial for stability but may reduce range of motion. This review provides an overview of the current literature, which suggests that the subscapularis may have a more important role in RSA than originally thought.

Subscapularis Insufficiency: What’s All the Fuss About?

There has been increase attention to the surgical treatment of the subscapularis (SSC) tendon with risk of postoperative dysfunction and early failures following shoulder arthroplasty. Studies investigating the clinical results after shoulder arthroplasty indicate that SSC tendon detachment or incision techniques and rehabilitation concepts may impair SSC recovery and consequently the postoperative function. In response to these results, technical modifications have been proposed and evaluated anatomically, biomechanically, and clinically. The aim of this article is to give an overview of current SSC take-down approaches, subsequent repair techniques, and postoperative rehabilitation protocols as well as to present the diagnostic algorithm and clinical impacts of the increasingly acknowledged condition of SSC insufficiency following shoulder arthroplasty procedures.

Current concepts in the primary management of irreparable posterosuperior rotator cuff tears without arthritis

Various procedures exist for patients with irreparable posterosuperior rotator cuff tears (IRCT). At present, no single surgical option has demonstrated clinical superiority.There is no panacea for treatment and patients must be aware, in cases of palliative or non-prosthetic options, of an alarming rate of structural failure (around 50%) in the short term.The current review does not support the initial use of complex and expensive techniques in the management of posterosuperior IRCT.Further prospective and comparative studies with large cohort populations and long-term follow-up are necessary to establish effectiveness of expensive or complicated procedures such as superior capsular reconstruction (SCR), subacromial spacers or biological augmentation as reliable and useful alternative treatments for IRCT. Cite this article: EFORT Open Rev 2018;3 DOI: 10.1302/2058-5241.3.180002.

Subscapularis-On Approach in Reverse Shoulder Arthroplasty

Using a subscapularis- and deltoid-preserving anterior approach is an option for patients undergoing reverse shoulder arthroplasty. Outcomes are better at short term than compared with the standard deltopectoral approach. Maintaining the integrity of the subscapularis tendon and preserving the deltoid muscle minimizes the need for postoperative immobilization and rehabilitation, allowing the patient to achieve active shoulder range of motion more rapidly, without increasing the incidence of shoulder dislocation. Overall length of hospital stay and duration of postoperative physical therapy are minimized, leading to significant economic gain. Future studies with longer follow-up are required to document the potential long-term benefits of this surgical technique.

Level of Evidence of the study: Review, Level IV