Short to mid-term results of stemless reverse shoulder arthroplasty in a selected patient population compared to a matched control group with stem

The radiographic and clinical outcomes of stemless reverse total shoulder arthroplasty: a minimum 2-year follow-up study

Background

The purpose of this study was to examine the radiographic and clinical outcomes of stemless reverse total shoulder arthroplasty (RTSA) after a minimum 2-year follow-up.

Methods

Between July 2018 and March 2023, 50 patients underwent 50 stemless RTSA with the Lima component. Twenty-eight patients with a follow-up of more than 2 years were reviewed. The average age was 71.9 years (range, 61-85 years), and the average follow-up period was 2.2 years (range, 2.0-5.1). Bone marrow density of the proximal humerus was measured before RTSA. We evaluated preoperative and postoperative range of motion, clinical score, radiographic change, and postoperative complications.

Results

Significant increases were observed postoperatively in forward flexion (112.0º-162.5º, P<0.01) and internal rotation (from L3 to T12 level; P<0.05). No changes were observed in external rotation (from 43.0º to 45.2º; P=0.762). The clinical scores improved for Korean Shoulder Scoring system (from 64 to 93, P<0.01) and American Shoulder and Elbow Surgeons score (from 17.5 to 27.3, P<0.01). Although radiolucent lines of less than 2 mm were observed in all cases, no osteolysis and loosening of the stemless humeral component was found. Scapular notching was observed in 18 cases (64.3%).

Conclusions

Stemless RTSA showed good radiographic and clinical results after a minimum 2-year follow-up. Level of evidence: IV.

Stemless Reverse Shoulder Arthroplasty Grants Satisfactory Clinical Scores at Minimum 5 Year Follow-up: Comparative Study

Purpose

To compare outcomes, between stemmed and stemless reverse shoulder arthroplasty (RSA) at a minimum follow-up of 5 years.

Methods

The authors retrospectively assessed a consecutive series of 45 patients that underwent RSA between September 2014 and October 2018 (23 stemless and 22 stemmed). All patients underwent plain anteroposterior and scapular Y-view radiographs for assessment immediately post-operatively and at final follow-up. At a minimum follow-up of 5 years, an independent observer assessed the clinical scores, including Constant score, QuickDASH score, and American Shoulder and Elbow Surgeons score.

Results

Of the 45 patients that underwent RSA, 5 patients died (11%), 2 were revised due to infection (4%), and 4 patients were lost to follow-up (9%). This left a final cohort of 34 patients (18 stemless and 16 stemmed). Significant differences between groups were found immediately post-operatively for lateralisation shoulder angle (LSA) (p = 0.021), but at 5 years post-operative for distalisation shoulder angle (DSA) (p = 0.017) and QuickDASH scores (p = 0.041) (Table 4), while the outcomes were comparable for absolute Constant scores, ASES score, and range of motion. Finally, stemless RSA had a 17% complication rate, while stemmed RSA had a 31% complication rate.

Conclusion

Stemless RSA had significantly more lateralisation, and significantly less distalisation, compared to stemmed RSA. Furthermore, at a 5-year follow-up, stemless RSA granted significantly greater QuickDASH scores. Finally, stemless RSA had comparable complication rates as stemmed RSA. The clinical relevance of this study is that stemless RSA is a safe alternative to stemmed RSA, while granting comparable or greater scores.Level of Evidence: III, Comparative Study.

Does the stemless reverse arthroplasty compare to a conventional stemmed implant? Clinical and radiographic evaluation at 2 years' minimum follow-up

BACKGROUND

Reverse shoulder arthroplasty (RSA) is a well-recognized treatment for many shoulder conditions, including rotator cuff arthropathy, primary glenohumeral joint arthritis, and rheumatoid arthritis, and can be used in both trauma and revision settings. Over the past 10 years, its popularity in New Zealand has been increasing, with a 6%-7% annual growth rate during this period. Stemless RSA designs have the following proposed advantages: They can preserve humeral bone stock, they can limit periprosthetic fractures, and they can be indicated in patients with abnormal diaphyseal humeral anatomy. To date, only 1 study has evaluated the outcomes of the Lima SMR Stemless implant. We present our data with an aim to report how the stemless reverse arthroplasty compares to a conventional stemmed implant.

METHODS

We performed a retrospective review of a consecutive series of patients treated at a single institution between 2015 and 2020. The endpoint was defined as final follow-up at a minimum of 2 years. Patients were excluded from the final analysis if they underwent revision. Thirty-three patients were identified as having undergone stemless RSA. Thirty patients had patient-reported outcome measures and radiographs at a minimum of 2 years' follow-up. Three patients had undergone revision within 2 years. The same sample size of stemmed RSAs (n = 33) was selected for comparison.

RESULTS

A total of 60 patients were included in the final analysis, of whom 30 underwent stemless RSA and 30 underwent stemmed RSA. The demographic characteristics of the 2 groups were comparable except age at operation, which showed a statistically significant difference (P = .001): 77 years (stemmed) vs. 65 years (stemless). The mean Oxford Shoulder Score was 40.1 in the stemless group vs. 40 in the stemmed group. The mean American Shoulder and Elbow Surgeons score was 72.9 in the stemless group vs. 79 in the stemmed group. Patient-reported outcome measures, pain scores, and satisfaction ratings were not statistically significantly different between the 2 groups. In terms of radiographic data, subsidence was observed in 2 patients in the stemless RSA group but the patients had no clinical symptoms. Also in the stemless RSA group, 1 patient had an acromial stress fracture and 1 patient had a superficial wound infection successfully treated with oral antibiotics. In terms of revisions in the stemless RSA group, 1 patient underwent revision owing to chronic infection, 1 underwent revision as a result of a periprosthetic fracture after a fall, and 1 underwent revision for gross instability.

CONCLUSIONS

The early results of sRSA are promising, and the stemless implant shows similar outcomes to a conventional stemmed implant.

Evolution of Stemless Reverse Shoulder Arthroplasty: Current Indications, Outcomes, and Future Prospects

Reverse total shoulder arthroplasty (rTSA) is increasingly being used as a reliable option for various shoulder disorders with deteriorated rotator cuff and glenohumeral joints. The stemless humerus component for shoulder arthroplasties is evolving with theoretical advantages, such as preservation of the humeral bone stock and decreased risk of periprosthetic fractures, as well as clinical research demonstrating less intraoperative blood loss, reduced surgical time, a lower rate of intraoperative fractures, and improved center of rotation restoration. In particular, for anatomical total shoulder arthroplasty (aTSA), the utilization of stemless humeral implants is gaining consensus in younger patients. The current systematic review of 14 clinical studies (637 shoulders) demonstrated the clinical outcomes of stemless rTSA. Regarding shoulder function, the mean Constant-Murley Score (CS) improved from 28.3 preoperatively to 62.8 postoperatively. The pooled overall complication and revision rates were 14.3% and 6.3%, respectively. In addition, recent studies have shown satisfactory outcomes with stemless rTSA relative to stemmed rTSA. Therefore, shoulder surgeons may consider adopting stemless rTSA, especially in patients with sufficient bone quality. However, further long-term studies comparing survivorship between stemless and stemmed rTSA are required to determine the gold standard for selecting stemless rTSA.

Radiologic, clinical, and patient-reported outcomes in stemless reverse shoulder arthroplasty at a mean of 46 months

BACKGROUND

The humeral stem can be a cause of problems in shoulder arthroplasty, for example, loss of bone stock, intraoperative and postoperative periprosthetic fractures, or postoperative infections involving the medullary canal. Therefore, stemless reverse shoulder arthroplasty (slRSA) has gained popularity, particularly in terms of preserving bone stock. However, there are limited data available on the midterm outcomes of slRSA. The objective of this study was to evaluate the clinical, radiologic, and patient-reported outcomes of slRSA at a minimum follow-up period of 2 years.

METHODS

Data on all stemless reverse shoulder prostheses implanted between January 2016 and October 2020 were collected. Patients were followed up at 6 weeks and 6, 12, and 24 months postoperatively. Clinical and radiologic data as well as patient-reported outcome measures were assessed with validated questionnaires (University of California at Los Angeles Shoulder Score [UCLA], American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form [ASES], Quick Disabilities of the Arm, Shoulder, and Hand questionnaire [Quick-DASH], visual analog scale [VAS] for pain, Subjective Shoulder Value [SSV], and Constant-Murley score [CS]). All patients had a minimum follow-up of 2 years.

RESULTS

During the observation period, 26 shoulders in 25 patients fulfilled the inclusion criteria. The mean follow-up was 46.8 months (range 25-66). The mean age was 70.1 years (range 59.9-86.4). At the most recent follow-up, a significant improvement was noted in the ASES score (55.9 ± 19.9 vs. 85.6 ± 10.7, P < .001), SSV (44.3 ± 18.7 vs. 85.3 ± 10.4, P < .001), Quick-DASH score (40.6 ± 22.0 vs. 17.8 ± 13.9, P < .001), VAS pain score (4.6 ± 3.2 vs. 0.9 ± 1.2, P < .001), and range of motion in flexion (66 ± 53 vs. 154 ± 22, P < .001) as well as in the absolute (44.1 ± 18.7 vs. 83.1 ± 10.1, P < .001) and relative CS (62.1 ± 27.8 vs. 111.9 ± 13.3, P < .001). Scapular notching was observed in 16% of cases, and radiolucent lines were detected in 28% of cases without symptoms of implant loosening. No revision was necessitated by any causes related to the stemless humeral component. Hence, implant survivorship was 100%.

CONCLUSIONS

With an ASES score showing a 30-point improvement and thus exceeding the minimal clinically important difference of 21 points and no revisions due to the stemless component, these results indicate that slRSA is a viable option, providing good to excellent midterm outcomes that are comparable to those of stemmed reverse shoulder prostheses, with the added advantage of bone stock preservation.

[Reverse Shoulder Arthroplasty - Current Concepts]

Due to first promising long term outcome data, reverse shoulder arthroplasty experienced an immense increase of usage during the past decade. Moreover, the initial Grammont concept has constantly been refined and adapted to current scientific findings. Therefore, clinical and radiological problems like scapular notching and postoperative instability were constantly addressed but do still remain an area of concern.This article summarises current concepts in reverse shoulder arthroplasty and gives an overview of actual indications like cuff tear arthropathy, severe osteoarthritis, proximal humerus fractures, tumours, fracture sequelae as well as revision surgery and their corresponding clinical and radiological results.

Stemless Reverse Shoulder Arthroplasty

Since the Food and Drug Administration (FDA) approval nearly two decades ago, the indications for and utilization of reverse shoulder arthroplasty (RSA) have expanded considerably. Stemless RSA designs have been used in Europe since 2005, but have only recently been introduced in domestic Investigational Device Exemption trials. Potential advantages of stemless RSA are similar to those of stemless anatomic total shoulder arthroplasty, which may include fewer shaft-related complications, avoidance of stress shielding, bone preservation, and easier revision surgery. European data support similar outcomes between certain stemless RSA prostheses compared with that of stemmed RSA implants at early and mid-term follow-up. However, long-term outcomes remain to be seen and differences exist between the stemless RSA designs used in Europe and those being studied in domestic clinical trials. An understanding of the potential advantages and disadvantages of stemless RSA, differences between existing designs, and reported clinical outcomes is prudent for the safe and meaningful implementation of this new technology in the United States.

Stemless reverse shoulder arthroplasty: clinical and radiologic outcomes with minimum 2 years' follow-up

BACKGROUND

Recently, a stemless reverse shoulder arthroplasty (RSA) design was developed to preserve bone stock. Clinical and radiologic studies of this design in larger cohorts with >100 patients are not frequent. The purpose of this study was to present the clinical and radiologic results of a newly developed stemless RSA implant. The hypothesis was that this design would provide similar clinical and radiologic results to other stemless implants, as well as stemmed implants.

METHODS

Between September 2015 and December 2019, all patients who underwent primary RSA with a stemless Easytech prosthesis were considered eligible for inclusion in this prospective multicenter study. The minimum follow-up period was 2 years. Clinical outcomes consisted of the Constant score, adjusted Constant score, QuickDASH (short version of Disabilities of the Arm, Shoulder and Hand questionnaire) score, Subjective Shoulder Value, and American Shoulder and Elbow Surgeons shoulder score. Radiographic parameters included radiolucency, loosening, scapular notching, and specific geometric parameters.

RESULTS

Stemless RSA was performed in 115 patients (61 women and 54 men) at 6 different clinical centers. The average age at the time of surgery was 68.7 years. The average Constant score was 32.5 preoperatively and showed significant improvement to 61.8 at latest follow-up (P < .001). The Subjective Shoulder Value also demonstrated significant improvement postoperatively (from 27.0 to 77.5, P < .001). Scapular notching was observed in 28 patients (24.3%); humeral loosening, 5 (4.3%); and glenoid loosening, 4 (3.5%). The total complication rate was 17.4%. Eight patients (4 women and 4 men) underwent implant revision.

CONCLUSION

The clinical outcomes of the examined stemless RSA seem to be comparable to those of other humeral designs; however, the complication and revision rates are higher than those of historical controls. Surgeons should proceed with caution when using this implant until longer-term follow-up data are available.

Preoperative metaphyseal cancellous bone density is associated with intraoperative conversion to stemmed total shoulder arthroplasty

Background

Methods to determine whether a stemless humeral component is appropriate for anatomic total shoulder arthroplasty are varied and often subjective. Objective preoperative data regarding metaphyseal bone quality may help guide surgical decision-making. This study sought to evaluate preoperative proximal humeral bone quality and determine whether it is predictive of intraoperative conversion to a stemmed humeral component.

Methods

Consecutive patients who underwent primary anatomic total shoulder arthroplasty from a single-surgeon practice were enrolled. All patients received a preoperative computed tomography (CT) scan for surgical templating purposes. The exclusion criteria were lack of a preoperative CT scan, preoperative plan for a stemmed component, and intraoperative conversion to a stem for a reason other than bone quality (ie, fracture). Preoperative CT scans were analyzed with an automated templating software. Cortical index and thickness were calculated, and bone density of the proximal diaphysis, cancellous metaphysis, and cortical metaphysis was obtained by averaging Hounsfield units (HU) across anatomically defined regions using a previously validated technique. The decision to convert to a stemmed humeral component was made intraoperatively based on a lack of stability of the trial stemless component. Bone quality measurements were compared between stemless and stemmed groups. An exact logistic regression was used incorporating gender and age.

Results

A total of 79 patients who underwent primary anatomic total shoulder arthroplasty were included in this study. Of these patients, 6 underwent intraoperative conversion to a stemmed humeral component (7.6%). There was no significant difference between cohorts in terms of cortical index and bone density within the proximal diaphysis and cortical metaphysis. On univariate analysis, cortical thickness, metaphyseal cancellous bone density, and gender were significantly different between groups. Patients receiving a stem had significantly lower metaphyseal cancellous bone density than those receiving stemless components (5.5 ± 11.2 HU vs. 47.6 ± 29.4 HU, P<.001). All patients converted to stems were female individuals (P = .01) and had metaphyseal cancellous bone density less than 20 HU (P<.001).

Conclusions

Metaphyseal cancellous bone density can be calculated on preoperative CT scans and is associated with intraoperative conversion to a stemmed humeral component in anatomic shoulder arthroplasty. A threshold of 20 HU can be used to predict which patients are more likely to require stemmed components.

How common is nerve injury after reverse shoulder arthroplasty? A systematic review

BACKGROUND

Nerve injury following reverse shoulder arthroplasty (RSA) is a known risk factor with wide ranging incidences reported. This systematic review evaluates the overall incidence of nerve injury following primary and revision RSA and summarizes the characteristics of the nerve injuries reported in the current literature.

METHODS

A systematic review was performed using separate database searches (Pubmed, Embase, Web of Science, Cochrane) following the PRISMA guidelines. Search criteria included the title terms "reverse shoulder," "reverse total shoulder," "inverted shoulder," and "inverted total shoulder" with publication dates ranging from 01/01/2010 to 01/01/2022. Studies that reported neurological injuries and complications were included and evaluated for primary RSA, revision RSA, number of nerve injuries, and which nerves were affected.

RESULTS

After exclusion, our systematic review consisted of 188 articles. A total of 40,146 patients were included, with 65% female. The weighted mean age was 70.3 years. The weighted mean follow-up was 35.4 months. The rate of nerve injury after RSA was 1.3% (510 of 40,146 RSAs). The rate of injury was greater in revision RSA compared to primary RSA (2.4% vs. 1.3%). Nerve injury was most common in RSAs done for a primary diagnosis of acute proximal humerus fracture (4.0%), followed by cuff tear arthropathy (3.0%), DJD (2.6%), and inflammatory arthritis (1.7%). Massive rotator cuff tears and post-traumatic arthritis cases had the lowest nerve injury rates (1.0% and 1.4%, respectively). The axillary nerve was the most commonly reported nerve that was injured in both primary and revision RSA (0.6%), followed by the ulnar nerve (0.26%) and median nerve (0.23%). Brachial plexus injury was reported in 0.19% of overall RSA cases.

CONCLUSION

Based on current English literature, nerve injuries occur at a rate of 1.3% after primary RSA compared with 2.4% after revision RSA. The most common nerve injury was to the axillary nerve (0.64%), with the most common operative diagnosis associated with nerve injury after RSA being acute proximal humerus fracture (4.0%). Surgeons should carefully counsel patients prior to surgery regarding the risk of nerve injury.

Stemless shoulder arthroplasty

The concept of stemless shoulder arthroplasty was born in 2005. It is now a valid option in the context of either anatomical or reverse shoulder replacement. Several questions have come up over our 15 years of using this system: How was the stemless shoulder arthroplasty concept born? It was motivated by a desire to have epiphyso-metaphyseal fixation using a corolla-shaped impacted anchor design. What are the features of commercially available stemless shoulder arthroplasty implants? The stemless anatomical implants now available have either a cage or central peg that is impacted or a system that is screwed into the epiphysometaphyseal bone. Several companies have introduced stemless reverse implants, some of which have an onlay configuration. How do the results of stemless implants compare to those of traditional stemmed implants? At a mean follow-up of 10 years, the outcomes of stemless TSA can be superimposed with those of traditional stemmed TSA. What are the advantages of stemless shoulder implants? The advantages are their simple implantation, ability to adapt to patient morphology and any malunions, various orientation angles, no stress-shielding, reduced risk of infection and bleeding and less complex revision surgery (if needed). What are the limitations or drawbacks of using stemless implants? The two main limitations are insufficient metaphyseal bone stock and poor bone quality, especially for reverse configurations. What does the future hold for stemless shoulder arthroplasty? Like with traditional stemmed implants, the longevity of stemless shoulder arthroplasty depends on its tribology, which can still be improved. In the future, a stemless implant will need to be convertible like stemmed humeral implants, and if possible, provide an inlay reverse configuration.

Can the Single Assessment Numeric Evaluation (SANE) be used as a stand-alone outcome instrument in patients undergoing total shoulder arthroplasty?

BACKGROUND AND HYPOTHESIS

There is no consensus as to which patient-determined shoulder outcome scores should be considered when analyzing patient outcomes for either clinical or research purposes. Use of multiple patient-determined outcomes may be redundant and cause increased responder burden. To date, the Single Assessment Numeric Evaluation (SANE) has not been widely accepted as a stand-alone shoulder-specific outcome measure. The hypothesis of this study was that the SANE would correlate with and be equal or superior in responsiveness to other outcome measures that have been used in a stand-alone fashion in patients undergoing total shoulder arthroplasty (American Shoulder and Elbow Surgeons [ASES], Western Ontario Osteoarthritis of the Shoulder [WOOS], and Simple Shoulder Test [SST] scores). In addition, it was hypothesized that the SANE would be more relevant to each patient than the ASES assessment, further supporting the use of the SANE as a stand-alone shoulder-specific outcome measure.

METHODS

A retrospective review of a database of patients undergoing total shoulder arthroplasty was performed, in which the SANE score was recorded simultaneously with the ASES, WOOS, and/or SST score. Correlations were determined using the Pearson coefficient. Subgroup analysis was performed to determine whether correlations differed in (1) preoperative outcome and (2) postoperative outcome determinations. Responsiveness was determined by calculating the standardized response mean and the effect size of all scores. The relevance of the SANE and ASES assessments was examined using the scores of 150 consecutive patients to determine the number of questions on each assessment that were not answered.

RESULTS

Correlation was excellent for the SANE score and the ASES score (n = 1447, r = 0.82, P < .0001), WOOS score (n = 1514, r = 0.83, P < .0001), and SST score (n = 1095, r = 0.81, P < .0001). The correlation of preoperative scores was moderate and that of postoperative scores was strong-moderate when the SANE score was compared with all 3 other scores. All scores were highly responsive, with standardized response mean values of 2.2 for the SANE score, 2.3 for the ASES score, 1.4 for the WOOS score, and 1.6 for the SST score. The effect size of the SANE score was 2.9; ASES score, 2.9; WOOS score, 2.9; and SST score, 2.3. One hundred percent of the SANE questions were answered completely compared with 61% of the ASES questions (P < .0001).

CONCLUSION

In patients undergoing total shoulder arthroplasty, the SANE score highly correlated with the WOOS, ASES, and SST scores, which have been used as stand-alone shoulder-specific outcome measures. The SANE score may provide the same information as the WOOS, ASES, and SST score regarding outcomes with a significant reduction in responder burden. It is logical that the SANE can be used as a stand-alone instrument for patients undergoing total shoulder arthroplasty.

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.

Stemless reverse total shoulder arthroplasty: a systematic review

BACKGROUND

The use of reverse total shoulder arthroplasty and stemless anatomic total shoulder replacement has been increasing in the United States every year. Stemless humeral components in reverse total shoulder arthroplasty are only approved for clinical trials in the United States with an investigational device exception with limited data.

METHODS

A systematic review on stemless reverse total shoulder arthroplasty was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. A search was conducted on November 25, 2020, using the MEDLINE/PubMed, Cochrane, and Embase databases. All articles were reviewed by 2 independent evaluators, with any conflicts or issues resolved by consensus or a final decision by the senior author. The primary outcomes extracted were complications, radiographic results, and outcome scores.

RESULTS

We evaluated 10 studies that used either the Total Evolutive Shoulder System (TESS) or Verso implant. There were 430 total patients and 437 total procedures; 266 patients in the TESS group underwent a total of 272 procedures, and 164 patients in the Verso group underwent a total of 165 procedures. The mean age at the time of surgery was 73.8 years (range, 38-93 years). The mean follow-up period ranged from 6.4 to 101.6 months per study. There was an overall trend of improved clinical outcome scores, a 0.2% humeral component loosening rate, and an 11.2% complication rate.

CONCLUSIONS

This review shows that the clinical and functional outcomes following stemless or metaphyseal reverse total shoulder arthroplasty are quite promising, especially with the low rate of humeral-sided complications. There continues to be a need for additional long-term studies and randomized clinical trials.

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

PURPOSE OF REVIEW

The purpose of this review is to summarize recent literature regarding the latest design modifications and biomechanical evolutions of reverse total shoulder arthroplasty and their impact on postoperative outcomes.

RECENT FINDINGS

Over the past decade, worldwide implantation rates of reverse total shoulder arthroplasty have drastically increased for various shoulder pathologies. While Paul Grammont's design principles first published in 1985 for reverse total shoulder arthroplasty remained unchanged, several adjustments were made to address postoperative clinical and biomechanical challenges such as implant glenoid loosening, scapular notching, or limited range of motion in order to maximize functional outcomes and increase the longevity of reverse total shoulder arthroplasty. However, the adequate and stable fixation of prosthetic components can be challenging, especially in massive osteoarthritis with concomitant bone loss. To overcome such issues, surgical navigation and patient-specific instruments may be a viable tool to improve accurate prosthetic component positioning. Nevertheless, larger clinical series on the accuracy and possible complications of this novel technique are still missing.

Acute versus delayed reverse total shoulder arthroplasty for proximal humeral fractures: a consecutive cohort study

BACKGROUND

The treatment of displaced proximal humeral fractures (PHFs) remains controversial. Open reduction-internal fixation (ORIF) can be challenging, especially in elderly patients with poor bone quality, whereas hemiarthroplasty has had unpredictable outcomes. Conservative treatment may result in severe fracture sequelae with poor outcomes, requiring late reverse total shoulder arthroplasty (RTSA) in many cases. The past few years have seen a shift toward the use of RTSA for the treatment of PHFs. The aim of this study was to compare the outcomes of RTSA between patients with acute fractures and patients who underwent delayed RTSA for fracture sequelae. Our hypothesis was that the outcomes of RTSA for acute PHFs would be better than those of delayed RTSA for fracture sequelae.

METHODS

We followed up 36 patients with a mean age of 79.1 years who underwent primary RTSA for acute PHFs and 56 patients with a mean age of 72.1 years who underwent RTSA in delayed fashion for fracture sequelae, including failed ORIF. The minimum follow-up period was 24 months. The mean follow-up period was 39.3 months in the acute RTSA group and 56.6 months in the delayed RTSA group. Demographic data, radiographs, and surgery data were prospectively collected and analyzed. At final follow-up, range of motion and radiographic analysis findings, as well as the Subjective Shoulder Value (SSV) and Constant score (CS), were recorded.

RESULTS

The clinical results favored the group undergoing acute RTSA for acute PHFs, with a mean SSV of 8.3 of 10 and adjusted CS of 88.9% compared with a mean SSV of 8.0 of 10 and adjusted CS of 77.6% in the group undergoing late RTSA for fracture sequelae-but without statistically significant differences between the groups. Although the acute RTSA group showed slightly better range-of-motion values, no statistically significant differences were found between the groups. No intraoperative complications occurred. The time from injury to the regaining of good pain-free function was significantly shorter in the acute RTSA group.

CONCLUSION

Although there were no statistically significant differences in outcomes between early RTSA for acute PHFs and late RTSA for fracture sequelae, the time from injury to the regaining of good pain-free function was significantly shorter in the acute RTSA group. Therefore, we advocate early RTSA for acute PHFs in elderly patients to provide a quicker recovery and an early return to good predictable outcomes with a much shorter period of pain and discomfort. In cases of failed conservative treatment, malunion, or failed ORIF, salvage RTSA has the potential to provide a good outcome.

Anatomic and Reverse Stemless Shoulder Arthroplasty: Functional and Radiological Evaluation

Background

Stemless shoulder arthroplasty was developed to restore the glenohumeral centre of rotation without violation of the humeral shaft. It allows the preservation of humeral bone stock. Complications related to stem malalignment and periprosthetic fractures can be avoided.

Patient and methods

This is a prospective observational study that reports outcomes of 46 patients who received stemless shoulder arthroplasty “Comprehensive Nano implant ®.” The series includes Group (A): 30 anatomic and one hemiarthroplasty. Group (B): 15 reverse stemless replacement. Functional outcomes were assessed by visual analog score (VAS), satisfaction, range motion, Constant score, and American Shoulder and Elbow Score (ASES).

Results

The mean follow-up was 40.4  ±  12 months (range, 24 months to 60 months). Group (A): VAS and satisfaction improved by 5.3 and 67.5 points respectively. Constant score significantly improved from 28.5  ±  14.5 to 62.5  ±  23 P = <0.001. The radiological assessment showed the mean centre of rotation (COR) deviation was 2.8  ±  1.9 mm. 27% of patients have COR discrepancy of more than 4 mm. In Group (B), patients reported a significant improvement in VAS, Satisfaction, and ASES P  =  0.002, 0.002, and 0.003, respectively.

Complications include shoulder pain with progressive loss of movements, aseptic loosening early subscapularis rupture, glenohumeral dislocations, and humeral component migration.

Conclusion

Anatomic Stemless total shoulder arthroplasty offers acceptable results and improvement of overall functional outcomes.

Clinical and radiological outcomes of a stemless reverse shoulder implant: a two-year follow-up in 56 patients

Background

Since the introduction of stemless anatomic shoulder arthroplasty, many studies have been published on anatomic implants. For reverse stemless implants, however, there are only a few clinical follow-up studies available. The current clinical case series aims to present clinical and radiological outcomes of a new stemless reverse prosthesis system (Lima Shoulder Modular Replacement stemless).

Methods

We prospectively evaluated the outcome of 56 stemless total shoulder arthroplasties in 56 patients with a mean age of 61.2 years (46-76 years) at the time of implantation at a minimum follow-up of 24 months (range 24-41 months). All patients were physically and radiologically examined. Clinical outcomes were evaluated by using the Constant-Murley Score and the Subjective Shoulder Value.

Results

The mean Subjective Shoulder Value was 84.27% at the latest follow-up. Significant improvements from preoperative to latest follow-up were documented for Constant-Murley Score (34.9 pts to 74.43 pts, P < .001) and active range of motion (abduction 72° to 130°, flexion 36° to 138°, and external rotation 16°to 28°). There was one complete loosening of the humeral component without reoperation. Radiolucency lines were observed in anteroposterior or axial radiographs at the humeral component in 23% of the cases, most of them in anteroposterior view at the calcar region. Radiolucency line findings did not affect clinical outcomes. Major complications or revisions did not occur so far.

Conclusion

At short-term follow-up, stemless reverse shoulder systems show comparable clinical and radiological outcomes compared to stemmed reverse implants in the literature.

Stemless reverse total shoulder arthroplasty: a systematic review of short- and mid-term results

INTRODUCTION

Stemless reverse total shoulder arthroplasty is used to treat rotator cuff deficient arthropathies, rheumatoid arthritis, and osteoarthritis. It has several advantages over the stemmed implant including preservation of bone stock, reduced surgical time, and easier revision.

METHODS

A systematic search was conducted in MEDLINE, EMBASE, PubMed, and CENTRAL to retrieve all relevant studies evaluating stemless reverse total shoulder arthroplasty.

RESULTS

The literature search identified 1993 studies out of which 7 studies were included in this review; 324 patients underwent stemless reverse total shoulder arthroplasty with a weighted mean age of 74.1 (SD = 8.6, range = 38 to 93) years and a weighted mean follow-up time of 44 (SD = 6.6, range = 3 to 95) months. The included studies reported significant improvements in range of motion and functional scores comparable to stemmed reverse total shoulder arthroplasty. The weight mean flexion and abduction was (135 ± 12)° and (131 ± 12)° post-operatively, respectively. The weighted mean constant score increased from (26.7 ± 5.2) Patients (pts) to (63.0 ± 8.0) pts post-operatively. Overall complication and revision rate were 12.3% and 5.2%.

CONCLUSION

Early and mid-term results indicate stemless reverse total shoulder arthroplasty has similar clinical outcomes to stemmed reverse total shoulder arthroplasty. There was no radiological evidence of humeral loosening at the latest follow-up.

Regional apparent density correlations within the proximal humerus

Background

Bone quality influences humeral implant selection for shoulder arthroplasty. However, little is known about how well bone near the humeral resection represents more distal cancellous bone. This investigation aimed to quantify the correlations between the apparent density of sites near the humeral head resection plane and cancellous sites throughout the metaphysis.

Methods

Using computed tomography data from 98 subjects, apparent bone density was quantified in 65 regions throughout the proximal humerus. Pearson's correlation coefficient was determined comparing the density between samples from the humeral resection and all supporting regions beneath the resection. Mean correlation coefficients were compared for (i) each sample region with all support regions, (ii) pooling all sample regions within a slice, and (iii) considering sample regions correlated with only the support regions in the same anatomic section.

Results

Stronger correlations existed for bone sampled beneath the resection (0.33 ± 0.10≤ r ≤ 0.88 ± 0.10), instead of from the resected humeral head (0.22 ± 0.10≤ r ≤ 0.66 ± 0.14). None of sample region correlated strongly with all support regions; however, strong correlations existed when sample and support regions both came from the same anatomic section.

Discussion

Assessments of cancellous bone quality in the proximal humerus should be made beneath the humeral resection not in the resected humeral head; and each anatomic quadrant should be assessed independently.

Stemless reverse total shoulder arthroplasty: a systematic review of contemporary literature

PURPOSE

Reverse shoulder prostheses are increasingly used for treatment of rotator cuff tear arthropathy and other degenerative shoulder diseases. In recent years, aiming for bone stock preservation has led to the design of metaphyseal humeral components without a stem. The aims of this study were to evaluate the complication and reintervention rates, as well as the clinical and radiographic outcomes in patients who underwent reverse shoulder arthroplasty (RSA) with stemless implants.

METHODS

A systematic review of the literature was completed until May 2020 using PubMed, EMBASE, CINAHL and Cochrane databases, according to PRISMA guidelines.

RESULTS

The literature search revealed 2942 studies, of which 13 were included in this review, with a total of 517 patients and a mean follow-up between 6.4 and 101.6 months. The total complication rate was 6.5%, while 3.3% were humeral associated complications. Finally, the rate of shoulders that underwent a reintervention was 6.7%, with 1.4% relating to a humeral component reason. Stemless RSA led to substantial improvements in patient reported outcome measures and range of motion across all studies. Scapular notching was reported in 15.2%, and lucencies around humeral component were reported in 0.8% of shoulders.

CONCLUSION

Stemless RSA resulted in low complication and reintervention rates at the mid-term follow-up. The reported clinical and radiological outcomes showed that these prostheses have at least equivalent outcomes with their stemmed counterparts. Further studies are required to investigate the long-term longevity and performance of the stemless humeral implants.

LEVEL OF EVIDENCE

Level IV; Systematic Review.

Stemless Total Shoulder: A Review of Biomechanical Fixation and Recent Results

Introduction: Anatomic total shoulder arthroplasty is the replacement of the humeral head and glenoid surfaces with the goal of replicating normal anatomy. It is commonly utilized for patients with osteoarthritis, rheumatoid arthritis, and osteonecrosis, who have decreased range of motion (ROM), persistent pain, and loss of strength. Total shoulder Arthroplasty (TSA) is the third most common joint replacement in the United States. The incidence of TSA has been increasing, some data suggest that by the year 2025, TSA incidence may rise to 439,206 operations per year. In recent years, stemless total shoulder implants have become available. Results: These implants preserve bone stock while decreasing complications such as osteolysis, stress shielding and periprosthetic fracture. Stemless implants improve anatomic reconstruction and biomechanical function of the shoulder joint. Conclusion: Increasing amounts of data suggest stemless TSA to be a safe and effective technology that will become more common in the coming year.

Reverse total shoulder arthroplasty

AIMS

This systematic review asked which patterns of complications are associated with the three reverse total shoulder arthroplasty (RTSA) prosthetic designs, as classified by Routman et al, in patients undergoing RTSA for the management of cuff tear arthropathy, massive cuff tear, osteoarthritis, and rheumatoid arthritis. The three implant design philosophies investigated were medial glenoid/medial humerus (MGMH), medial glenoid/lateral humerus (MGLH), and lateral glenoid/medial humerus (LGMH).

METHODS

A systematic review of the literature was performed via a search of MEDLINE and Embase. Two reviewers extracted data on complication occurrence and patient-reported outcome measures (PROMs). Meta-analysis was conducted on the reported proportion of complications, weighted by sample size, and PROMs were pooled using the reported standardized mean difference (SMD). Quality of methodology was assessed using Wylde's non-summative four-point system. The study was registered with PROSPERO (CRD42020193041).

RESULTS

A total of 42 studies met the inclusion and exclusion criteria. Rates of scapular notching were found to be significantly higher in MGMH implants (52% (95% confidence interval (CI) 40 to 63)) compared with MGLH ((18% (95% CI 6 to 34)) and LGMH (12% (95% CI 3 to 26)). Higher rates of glenoid loosening were seen in MGMH implants (6% (95% CI 3 to 10)) than in MGLH implants (0% (95% CI 0 to 2)). However, strength of evidence for this finding was low. No significant differences were identified in any other complication, and there were no significant differences observed in PROMs between implant philosophies.

CONCLUSION

This systematic review has found significant improvement in PROMS and low complication rates across the implant philosophies studied. Scapular notching was the only complication found definitely to have significantly higher prevalence with the MGMH implant design. Cite this article: Bone Joint J 2021;103-B(5):813-821.

Comparison of stemless and conventional stemmed shoulder arthroplasties in shoulder arthropathy: A meta-analysis

BACKGROUND

It is unclear whether stemless shoulder prosthesis lead to better clinical outcomes than conventional stemmed shoulder prosthesis. The purpose is to compare clinical outcomes and complication rates after surgery in patients with shoulder arthropathy treated with stemless or conventional stemmed shoulder prosthesis.

METHOD

All studies comparing the constant score (CS), range of motion (ROM), and complication rates after surgery in patients with shoulder arthropathy treated with stemless or conventional stemmed shoulder prosthesis were included. The major databases MEDLINE, EMBASE, the Cochrane Library, Web of Science, and SCOPUS were searched for appropriate studies from the earliest available date of indexing through March 31, 2019. No restrictions were placed on language of publication.

RESULTS

A total of 6 studies met the inclusion criteria and were analyzed in detail. Overall postoperative ROM (95% CI: 3.27 to 11.92; P < .01) was significantly greater for stemless prosthesis compared to conventional stemmed prosthesis. However, postoperative CS (95% CI: -2.98 to 7.13; P = .42) and complication rates (OR 1.22, 95% CI: 0.48-3.08; P = .68) were did not differ significantly between the 2 groups.

CONCLUSION

This meta-analysis revealed that postoperative CS and complication rates did not differ significantly between the 2 treatment methods, stemless shoulder prosthesis and conventional stemmed shoulder prosthesis, for shoulder arthropathy. However, stemless shoulder prosthesis resulted in better outcomes than conventional stemmed shoulder prosthesis in terms of postoperative ROM.

LEVEL OF EVIDENCE

Level III, Therapeutic study.

Results of stemless shoulder arthroplasty: a systematic review and meta-analysis

Stemless shoulder arthroplasty relies solely on cementless metaphyseal fixation and is designed to avoid stem-related problem such as intraoperative fractures, loosening, stress shielding or stress-risers for periprosthetic fractures.

Many designs are currently on the market, although only six anatomic and two reverse arthroplasty designs have results published with a minimum of two-year follow-up.

Compared to stemmed designs, clinical outcome is equally good using stemless designs in the short and medium-term follow-up, which is also the case for overall complication and revision rates.

Intraoperative fracture rate is lower in stemless compared to stemmed designs, most likely due to the absence of intramedullary preparation and of the implantation of a stem.

Radiologic abnormalities around the humeral implant are less frequent compared to stemmed implants, possibly related to the closer resemblance to native anatomy.

Between stemless implants, several significant differences were found in terms of clinical outcome, complication and revision rates, although the level of evidence is low with high study heterogeneity; therefore, firm conclusions could not be drawn.

There is a need for well-designed long-term randomized trials with sufficient power in order to assess the superiority of stemless over conventional arthroplasty, and of one design over another.

Cite this article: EFORT Open Rev 2021;6:35-49. DOI: 10.1302/2058-5241.6.200067

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.

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

Background

Globally, reverse shoulder arthroplasty (RSA) has moved away from the Grammont design to modern prosthesis designs. The purpose of this 2-part study was to systematically review each of the most common complications of RSA, limiting each search to publications in 2010 or later. In this part (part I), we examined (1) scapular notching (SN), (2) periprosthetic infection (PJI), (3) mechanical failure (glenoid or humeral component), and (4) neurologic injury (NI).

Methods

Four separate PubMed database searches were performed following Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Overall, 113 studies on SN, 62 on PJI, 34 on mechanical failure, and 48 on NI were included in our reviews. Univariate analysis was performed with the χ² or Fisher exact test.

Results

The Grammont design had a higher SN rate vs. all other designs combined (42.5% vs. 12.3%, P < .001). The onlay humeral design had a lower rate than the lateralized glenoid design (10.5% vs. 14.8%, P < .001). The PJI rate was 2.4% for primary RSA and 2.6% for revision RSA. The incidence of glenoid and humeral component loosening was 2.3% and 1.4%, respectively. The Grammont design had an increased NI rate vs. all other designs combined (0.9% vs. 0.1%, P = .04).

Conclusions

Focused systematic reviews of the recent literature with a large volume of RSAs demonstrate that with the use of non-Grammont modern prosthesis designs, complications including SN, PJI, glenoid component loosening, and NI are significantly reduced compared with previous studies. As the indications for RSA continue to expand, it is imperative to accurately track the rates and types of complications to justify its cost and increased indications.

Outcomes of reverse shoulder arthroplasty using a short stem through a superolateral approach

BACKGROUND

Reverse shoulder arthroplasties have progressed in recent decades to become the most popular type of arthroplasty. Short stems with metaphyseal fixation have been developed to preserve bone stock and facilitate possible revision. Accurate positioning of these implants can be challenging using the superolateral approach.

OBJECTIVE

This study aimed to evaluate the clinical and radiologic results of reverse short-stem arthroplasties using a superolateral approach with a minimum of 2 years' follow-up.

METHODS

Between January 2015 and December 2016, a total of 76 patients underwent reverse shoulder arthroplasty surgery (79 shoulders) using a short uncemented humeral stem for shoulder arthritis with irreparable rotator cuff tear. Arthroplasties for post-traumatic osteoarthritis were excluded. Functional outcomes were assessed using Constant Score, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), visual analog scale (VAS), and range of motion. Radiographic analysis was used to evaluate component loosening, implant position, and implant filling ratio.

RESULTS

The mean age was 70.8 years. At a mean of 38.8-month follow-up, there were significant improvements in Constant score (44.2 to 87.9, P < .001), ASES score (36.2 to 84.3, P < .001), and VAS score (6.8 to 0.4, P < .001). Forward flexion improved from 89°to 131°(P < .001), and external rotation improved from 25° to 36°(P < .001). No evidence of periprosthetic loosening was visible. Mean varus of the humeral stem was 1°(±6°). The mean glenoidal inclination was 98°(±7°), which corresponds to a lower tilt of 8°. The average filling ratio was between 50% and 60% in both the metaphysis and the diaphysis.

CONCLUSION

The clinical results obtained in this study were satisfying, with a significantly low complication rate. Hence, short-stem reverse shoulder arthroplasty using a superolateral approach, while taking particular care to protect the deltoid, remains our method of choice.

The short- to midterm effectiveness of stemless prostheses compared to stemmed prostheses for patients who underwent total shoulder arthroplasty: a meta-analysis

BACKGROUND

To systematically compare the short- to midterm effectiveness of stemless prostheses to that of stemmed prostheses for patients who underwent total shoulder arthroplasty (TSA) and to provide a guideline for clinical decision-making.

METHODS

PubMed, the Cochrane Library, and Web of Science were searched with the given search terms until July 2019 to identify published articles evaluating the clinical outcomes for stemless prostheses compared with stemmed prostheses for patients who underwent TSA. Data extraction and the quality assessment of the included studies were independently performed by two authors. Stata software 14.0 was used to analyze and synthesize the data.

RESULTS

Two randomized controlled trials and six case-controlled studies with a total of 347 shoulders were included in this meta-analysis. The results of this meta-analysis showed that there were no significant differences between the stemless and stemmed prostheses in terms of the Constant score, pain score, strength, activities of daily living, postoperative range of motion (ROM), and postoperative maximum active ROM.

CONCLUSIONS

This is the first meta-analysis reporting the clinical results of stemless TSA in the short- to midterm follow-up period. Both types of shoulder prostheses were similar in achieving satisfactory clinical outcomes.

Determination of humeral inclination in stemless shoulder arthroplasty using plain radiographs

Plain radiographs of the shoulder are routinely used to assess implant orientation after shoulder arthroplasty. Recently, humeral inclination has come into focus especially in reverse stemless shoulder arthroplasty. But, in X-ray projections not exactly parallel to the base of the humeral component, the humeral inclination angle cannot be determined precisely. Therefore, we established a mathematical algorithm to calculate the humeral neck shaft angle and counterchecked the formula using plain radiographs of a sawbone model containing a humeral head prosthesis. With increasing angles of retroversion, the base of the humeral component forms an ellipse in plain radiographs. Knowing the width and length of the ellipse as well as the inclination angle in a plain radiograph, the exact inclination angle can be determined using the equation reported below. Thus, independent from the viewing angle or angle of retroversion, the inclination angle of a stemless humeral head implant can be estimated with an accuracy of ±1.5-degree deviation. The algorithm proposed may be the basis for further research on the impact of humeral inclination in stemless shoulder arthroplasty.

Reverse Total Shoulder Arthroplasty: Implant Design Considerations

PURPOSE OF REVIEW

Our understanding of the reverse total shoulder arthroplasty (RTSA) has grown exponentially since Grammont first introduced his design in 1985. There are a multitude of implant-related variables to consider when performing RTSA. The purpose of this article is to provide a review of these design considerations.

RECENT FINDINGS

Current literature demonstrates that the traditional Grammont prosthesis has over 90% survivorship at 10 years. Despite these promising results, there have been concerns raised over the significant rate of scapular notching observed. As a result, the traditional RTSA design has been modified to minimize this complication and maximize impingement-free motion. Modern RTSA designs with a cementless, curved, short-stemmed eccentric onlay humeral component combined with a large, lateralized glenosphere placed in 10° of inferior tilt with > 3.5 mm of inferior overhang have been found to provide excellent results. However, all implant design features must be considered on a case-by-case basis to optimize outcome for each patient. Humeral and glenoid implant design variables have evolved as the biomechanics of RTSA have been further elucidated. Consideration of these variables allows the surgeon to maximize joint efficiency, improve impingement-free range of motion, decrease the risk of scapular notching, preserve bone stock, and minimize the risk of instability.

Stemless shoulder arthroplasty: review of short and medium-term results

Background

The number of anatomic total shoulder (TSA), hemiarthroplasty (HA), and reverse total shoulder arthroplasties (RTSA) is rapidly increasing in the United States. Stemless shoulder arthroplasty has numerous theoretical advantages, including preserved bone stock, decreased operating time, reduced rate of intraoperative humerus fracture, and flexibility of anatomic reconstruction. Only recently studies with more than 5 years of mean follow-up have become available.

Methods

The MEDLINE database was systematically queried to identify all studies reporting outcomes regarding anatomic or reverse stemless shoulder arthroplasty. Studies were categorized according to mean reported follow-up. Outcome scores and range of motion measurements were compiled. Complication and revision rates due to failure of the humeral or glenoid components were summarized.

Results

Nineteen TSA and HA studies with a total of 1115 patients were identified, with 4 studies and 162 patients with a mean follow-up between 60 and 120 months. Six RTSA studies with a total of 346 patients were identified, all with a mean follow-up between 18 and 60 months. There was a reliable improvement in outcomes compared with preoperative scores across studies. A cumulative 0.7% (8 of 1115) humeral component complication rate was found for TSA and HA components. There was a cumulative 1.7% (6 of 346) humeral complication rate for RTSA prostheses.

Conclusions

In the studies reporting similar outcome measures, there were reliable improvements on par with stemmed counterparts. Aggregate complication rates appear similar to those published in the literature for stemmed components. Evidence supporting the utility and safety of stemless designs would be strengthened by longer-term follow-up and additional prospective comparative studies.

Long-term results of the reverse Total Evolutive Shoulder System (TESS)

INTRODUCTION

Latest trends in shoulder replacement aim at bone stock preservation. Long-term results of stemless anatomical total shoulder implants compare favourably with stemmed designs in terms of function and survivorship. The Total Evolutive Shoulder System (TESS) has been one of the first designs offering a stemless implant not only for anatomical but also for reverse total shoulder arthroplasty with optional short stem attachment in cases with poor bone quality. The aim of the present study was to evaluate long-term results of the reverse Total Evolutive Shoulder System (TESS).

MATERIALS AND METHODS

Between 2006 and 2009, 49 shoulders in 47 patients were replaced using the Biomet reverse Total Evolutive Shoulder System (TESS). 29 shoulders in 27 patients who were aged 72.4 ± 6.7 (53-88) years were available for review at a mean follow-up of 101.6 ± 24.6 (75-142) months.

RESULTS

The implant survival rate was 93.1% at 101 months (8.4 years). The overall revision rate of the TESS implant was 17.2%. No implant associated complications to the reverse corolla implant could be observed. All reverse corolla implants showed solid fixation at follow-up. Scapular notching was found in 72.3% of the shoulders. Clinical scores significantly improved at long-term follow-up (VAS from 7.5 ± 1.2 to 1.4 ± 1.5, p < 0.001; quick-DASH from 70.9 ± 12.0 to 28.9 ± 22.9, p < 0.001 and Constant score from 13.0 ± 3.7 to 60.5 ± 16.8, p < 0.001).

CONCLUSIONS

In terms of clinical scores, radiographic loosening, complication rates and implant survivorship the reverse Total Evolutive Shoulder System provides results comparable to those of conventional stemmed reverse shoulder arthroplasty.

Radiographic restoration of native anatomy: a comparison between stemmed and stemless shoulder arthroplasty

BACKGROUND

Shoulder arthroplasty is a reliable procedure for patients with degenerative glenohumeral disease, and reproduction of native shoulder anatomy leads to superior outcomes. The aim of this study was to compare the ability of stemmed and stemless implants to radiographically restore native glenohumeral anatomy.

METHODS

Shoulder arthroplasties were performed in 79 patients, with 58 receiving a stemless implant and 21 receiving a stemmed implant. Preoperative and postoperative radiographs were assessed for humeral head height, humeral head centering, humeral head medial offset, humeral head diameter, humeral neck angle, and lateral humeral offset by 2 independent viewers. Measurements were scored and summed to identify the anatomic reconstruction index (ARI). Radiographic measurements were compared using the Student t test, and significance was set at P < .05 for all statistical analyses. Interobserver agreement of radiographic analyses was assessed using the intraclass correlation coefficient, finding excellent reliability (intraclass correlation coefficient, 0.92).

RESULTS

Five of six radiographic measurements along with the calculated ARI demonstrated no differences between stemmed and stemless shoulder implants (humeral head diameter, P = .651; humeral head height, P = .813; humeral head medial offset, P = .592; lateral humeral offset, P = .311; humeral head centering, P = .414; and ARI, P = .862). Stemless implants showed improved restoration of the native humeral neck angle (0° for stemless vs. -3° for stemmed, P = .017).

CONCLUSION

Radiographic restoration of anatomy is similar for stemmed and stemless shoulder arthroplasty implants.

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.

Cementless metaphyseal reverse shoulder arthroplasty: our preliminary experience

Reverse shoulder arthroplasty (rTSA) is a largely used procedure with a wide variety of indications. The incidence of this surgery is increased in recent years and the literature expects similar trend for the future. Metaphyseal stem rTSA seems to be a promising solution considering major objectives the preservation of humeral bone stock and ease of revision. In our study we analyzed 19 patients treated with cementless metaphyseal stem rTSA for osteoarthritis (group A) and acute fractures (group B). In group A (7 patients) the average Constant score improved from 21,57 (16-29) to 56,85 (38-72), the average SST improved from 2,29 (1-4) to 9,43 (8-12) and the mean VAS score improved from 14,29 to 4,86. In group B (12 patients) the mean Constant-Murlay score at last follow up was 42,17; the average SST was 7 and average pain score was 8,92. Overall active range-of-motion (ROM) improved significantly. Surgical considerations, clinical (analyzing Constant score and Simple Shoulder Test) and radiological short-term outcomes are encouraging, with low rate of complications. Long term follow-up studies are necessary to confirm our findings and the potential benefits related to these implants. (www.actabiomedica.it)