Glenoid revision surgery after total shoulder arthroplasty

Primary and revision reverse total shoulder arthroplasty using a patient-matched glenoid implant for severe glenoid bone deficiency

BACKGROUND

Severe glenoid bone loss in the setting of both primary and revision reverse total shoulder arthroplasty (rTSA) continues to remain a significant challenge. The purpose of this study was to report on radiographic and clinical outcomes of primary and revision rTSA using a patient-matched, 3-dimensionally printed metal glenoid implant to address severe glenoid bone deficiency. This is a follow-up study to previously reported preliminary results.

METHODS

A retrospective review was performed on 62 patients with severe glenoid bone deficiency who underwent either primary or revision rTSA using the Comprehensive Vault Reconstruction System (VRS) (Zimmer Biomet) at a single institution. Preoperative and postoperative values for the Disabilities of the Arm, Shoulder and Hand (DASH), Constant, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), Simple Shoulder Test (SST), Single Assessment Numeric Evaluation (SANE), and visual analog scale (VAS) pain scores as well as active range of motion (ROM) were collected and compared using the Wilcoxon signed rank test with the level of statistical significance set at P < .05. The percentage of patients achieving minimal clinically important difference (MCID) and substantial clinical benefit (SCB) was also calculated.

RESULTS

Fifty-five of 62 shoulders (88.7%) were able to be contacted at a minimum of 2 years postoperatively, with 47 of 62 (75.8%) having complete clinical and radiographic follow-up with a mean age of 67.5 years (range, 48-85 years) and follow-up of 39.2 months (range, 25-56 months). There were 19 primary and 28 revision rTSAs. Significant improvements were seen in mean active forward flexion (63.1° ± 30.3° to 116.8° ± 35°), abduction (48.1° ± 16.1 to 76.2° ± 13.4°) (P < .001), external rotation (16° ± 23.7° to 32.1° ± 24.5°) (P < .005), DASH (59.9 ± 17.7 to 35.7 ± 24.3), Constant (23.4 ± 13.1 to 53.1 ± 17.4), ASES (27.8 ± 16.2 to 69.1 ± 25.2), SST (3.3 ± 2.5 to 7.6 ± 3.5), SANE (28.9 ± 18.3 to 66.7 ± 21.2), and VAS pain (7.1 ± 2.4 to 1.8 ± 2.6) scores (P < .001). MCID and SCB was achieved in a majority of patients postoperatively. The overall complication rate was 29.1%, with only 1 baseplate failure.

CONCLUSION

This study demonstrates promising evidence that the VRS implant can be used as a viable option to achieve clinically important improvement in a majority of patients treated for severe glenoid bone deficiency with rTSA in both the primary and revision setting.

Complications and Reinterventions of Reverse Total Shoulder Arthroplasty in a Korean Population: 14-Year Experience in Reverse Shoulder Arthroplasty

Background

There are few reports on the revision or reintervention of reverse total shoulder arthroplasty (RTSA) in South Korea. The purpose of this study was to evaluate the true incidence of complications and reintervention of RTSA and clinical and radiological outcomes based on our 14-year experience in RTSA in a Korean population.

Methods

Between March 2008 and June 2022, 412 consecutive cases of RTSA were performed in 388 patients with an average age of 74.4 years at our institute. Excluding 23 patients lost to follow-up, 365 patients (373 shoulders including 8 bilateral cases) who underwent primary RTSA with more than 6 months of follow-up were enrolled in this study. We evaluated those who had complications or reintervention including revision RTSA for failed RTSA. Patient charts were reviewed, and clinical outcomes including clinical scores, complications, and reintervention and radiologic outcomes were evaluated at the last follow-up.

Results

Among the 373 shoulders that underwent primary RTSA, complications were found in 50 patients (13.94%, 10 men and 40 women with a mean age of 75.9 ± 6.7 years [range, 51-87 years]). The causes of complications were as follows: 13 acromion, coracoid, or scapular spine fractures, 10 loosening (glenoid: 5, humeral stem: 5), 5 infections, 4 periprosthetic fractures, 2 instability, 2 neurologic complications, and 14 miscellaneous complications. Twenty patients (5.63%, 4 men and 16 women with a mean age of 74.2 ± 8.2 years [range, 51-87 years]) underwent reintervention. The interval to the first reintervention was 27.8 ± 23.1 months (range, 0.1-78 months). The causes of reintervention (20 cases) were 8 loosening (glenoid: 4, humeral stem: 4), 5 infections, 5 fractures, and 2 instability. Among them, 15 component revisions (4.02%) were performed. At the last follow-up, American Shoulder and Elbow Surgeons, University of California at Los Angeles, and Simple Shoulder Test scores were improved from 25.4, 12.4, and 1.6 preoperatively to 40.4, 16.2, and 3.2, respectively. Forward flexion (48° to 87°), abduction (52° to 79°), external rotation (18° to 22°), and internal rotation (buttock to L2) were improved.

Conclusions

After primary RTSA in a Korean population, the complication, reintervention, and revision rates were 13.94%, 5.63%, and 4.02%, respectively. Careful evaluation of the complications and adequate treatments should be performed.

Patient-specific implants in reverse shoulder arthroplasty

Reverse total shoulder arthroplasty (RTSA) is widely popular among shoulder surgeons and patients, and its prevalence has increased dramatically in recent years. With this increased use, the indicated pathologies associated with RTSA are more likely to be encountered, and challenging patient presentations are more likely to be seen. One prominent challenging presentation is RTSA patients with severe glenoid bone loss. Several techniques with varying degrees of invasiveness, including excessive reaming, alternate centerline, bone grafting, and patient-specific implants (PSIs), have been developed to treat patients with this presentation. PSI treatment uses a three-dimensional reconstruction of a computed tomography scan to design a prosthetic implant or component customized to the patient's glenoid morphology, allowing compensation for any significant bone loss. The novelty of this technology implies a paucity of available literature, and although many studies show that PSIs have good potential for solving challenging shoulder problems, some studies have reported questionable and equivocal outcomes. Additional research is needed to explore the indications, outcomes, techniques, and cost-efficiency of this technology to help establish its role in current treatment guidelines and strategies.

Yoke procedure as a salvage treatment option for failed reverse total shoulder arthroplasty with irreconstructible glenoid

BACKGROUND

Glenoid bone loss is a known challenge in primary and revision reverse total shoulder arthroplasty. In severe deficiency, even placing the baseplate in alternative centerline or using an augmented baseplate may be insufficient. This study reports on the use of a soft tissue resurfacing technique using Achilles tendon allograft, coined Yoke procedure, for salvage treatment of glenoid deficient shoulder requiring reconstruction.

MATERIALS AND METHODS

All patients who underwent the Yoke procedure between 2014 and 2020 by a single surgeon at a single academic center were identified and had their charts retrospectively reviewed. Demographics and surgical information were recorded. Preoperative X-rays and 3D-computed tomography scans were reviewed to classify patient glenoid types, evaluate glenoid medialization, and measure shoulder angles. Preoperative and postoperative range of motions and patient-reported outcome scores were evaluated, including anterior elevation, external rotation, internal rotation, visual analog scale, subjective shoulder value score, Simple Shoulder Test, and American Shoulder and Elbow Surgeons (ASES) scores. Postoperative radiographs and follow-up notes were reviewed to evaluate postoperative complication profiles at 1 year.

RESULTS

Seven patients with a median age of 69 years (range, 54-77 years) underwent Yoke procedure and had a median 12-month follow-up (range, 9-56 months). All patients were female and had a median of 2 prior shoulder surgeries (range, 0-13). Of all the patients, the most common comorbidity was osteoporosis (6) followed by rheumatoid arthritis (3). Of the 5 patients who had previous arthroplasty, the most common indications were baseplate failure (4), followed by instability (3) and infection (3). The median visual analog scale score improved from 8 (range, 3-9) to 2 (range, 1-4). The median Simple Shoulder Test improved from 8% (range, 0%-42%) to 33% (range, 17%-83%). The median ASES score improved from 15 (range, 5-38) to 52 (range, 40-78). The median anterior elevation and external rotation improved from 20° (range, 0°-75°) to 100° (range, 40°-145°) and 10° (range, 0°-20°) to 20° (range, 0°-55°), respectively. There was no change in median internal rotation. As of the last follow-up, one patient reported postoperative complications of anterior-superior implant escape, heterotopic ossification, and scapular notching.

CONCLUSION

The Yoke procedure is a promising salvage treatment that can offer patients consistent pain reduction and moderate functional improvements at short-term follow-up. In the setting of poor bone quality and severe glenoid deficiency, glenoid baseplate implantation may not be absolutely necessary for a pain-relieving, functionally acceptable outcome.

Custom-made Glenoid Baseplate and Intra-Operative Navigation in Complex Revision Reverse Shoulder Arthroplasty: A Case Report

Prosthetic instability is one of the most challenging complications to manage when considering reverse shoulder arthroplasty (RSA). Additional tools are available to improve accuracy in planning and execution of arthroplasties, such as 3-dimensional (3D) virtual planning based on computer tomography (CT) scan and intra-operative navigation. We report a case of an 84-year-old male treated for RSA prosthetic instability combined with severe glenoid deformity and bone loss, and subclinical periprosthetic joint infection (PJI). The definitive surgery consisted in implanting a customized metaglene component realized on the basis of the bone defect detected in the 3D-CT scan and implanted with the aid of computer-assisted intra-operative navigation. The patient was periodically followed-up for a year with clinical and radiological evaluations with the absence of further prosthetic dislocations nor PJI, a good overall satisfaction, a satisfying range of motion, and acceptable functional scores (American Shoulder and Elbow Surgeons Score 62, Constant-Murley Score 36). This is the first description, to our knowledge, of a customized glenoid baseplate implanted with the aid of intraoperative navigation. The combined use of 3D-CT planning and intra-operative computer-assisted navigation allows to manage complex cases of prosthetic revision surgery even where extensive bone defects are present.

Maximizing Implant Stability in the Face of Glenoid Bone Stock Deficiency

As the incidence of shoulder arthroplasty continues to rise, encountering significant glenoid bone loss in the primary and revision setting is becoming a common occurrence. To effectively treat these difficult scenarios, surgeons must understand the common patterns of glenoid bone loss and be aware of the various techniques available for treatment. Understanding bone loss requires careful pre-operative evaluation with appropriate imaging and pre-operative planning software. Treatment algorithms consist of primary anatomic and reverse arthroplasty as well as the use of allograft or autograft bone grafting, augmented glenoid components, specialized surgical techniques, or custom implant designs. Ultimately, good outcomes are able to be obtained with various techniques when applied to the appropriate clinical situation.

Use of custom glenoid components for reverse total shoulder arthroplasty

BACKGROUND

Our purpose was to evaluate a custom reverse total shoulder arthroplasty glenoid baseplate for severe glenoid deficiency, emphasizing the challenges with this approach, including short-term clinical and radiographic outcomes and complications.

METHODS

This was a single-institution, retrospective series of 29 patients between January 2017 and December 2022 for whom a custom glenoid component was created for extensive glenoid bone loss. Patients were evaluated preoperatively and at intervals for up to 5 years. All received preoperative physical examinations, plain radiographs, and computed tomography (CT). Intra- and postoperative complications are reported.

RESULTS

Of 29 patients, delays resulted in only undergoing surgery, and in three of those, the implant did not match the glenoid. For those three, the time from CT scan to implantation averaged 7.6 months (range, 6.1-10.7 months), compared with 5.5 months (range, 2-8.6 months) for those whose implants fit. In patients with at least 2-year follow-up (n=9), no failures occurred. Significant improvements were observed in all patient-reported outcome measures in those nine patients (American Shoulder and Elbow Score, P<0.01; Simple Shoulder Test, P=0.02; Single Assessment Numeric Evaluation, P<0.01; Western Ontario Osteoarthritis of the Shoulder Index, P<0.01). Range of motion improved for forward flexion and abduction (P=0.03 for both) and internal rotation up the back (P=0.02). Pain and satisfaction also improved (P<0.01 for both).

CONCLUSIONS

Prolonged time (>6 months) from CT scan to device implantation resulted in bone loss that rendered the implants unusable. Satisfactory short-term radiographic and clinical follow-up can be achieved with a well-fitting device. Level of evidence: III.

Clinical and radiologic outcomes of Lima ProMade custom 3D-printed glenoid components in primary and revision reverse total shoulder arthroplasty with severe glenoid bone loss: a minimum 2-year follow-up

BACKGROUND

The purpose of this study is to report the clinical and radiologic outcomes of patients undergoing primary or revision reverse total shoulder arthroplasty using custom 3D-printed components to manage severe glenoid bone loss with a minimum of 2-year follow-up.

METHODS

Following ethical approval, patients were identified and invited to participate. Inclusion criteria were (1) severe glenoid bone loss necessitating the need for custom implants and (2) patients with definitive glenoid and humeral components implanted more than 2 years prior. Included patients underwent clinical assessment using the Oxford Shoulder Score (OSS), Constant-Murley score, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), and the quick Disabilities of the Arm, Shoulder, and Hand questionnaire (QuickDASH). Radiographic assessment included anteroposterior and axial projections. Patients were invited to attend a computed tomography (CT) scan to confirm osseointegration. Statistical analysis used descriptive statistics (mean and standard deviation [SD]) and paired t test for parametric data.

RESULTS

Eleven patients declined to participate. Five patients were deceased prior to study commencement, leaving 42 remaining patients in this analysis. Three patients had revision surgery before the 2-year follow-up; of these, 2 retained their custom glenoid components. Mean follow-up was 31.6 months from surgery (range 24-52 months). All 4 scores improved: OSS from a mean 15 (SD 8.4) to 36 (SD 12) (P < .001), Constant-Murley score from a mean 15 (SD 11.2) to 52 (SD 20.1) (P < .001), QuickDASH from a mean 70 (SD 21) to 31 (SD 24.8) (P = .004), and the ASES score from a mean 22 (SD 17.8) to 71 (SD 23.3) (P = .007). Radiologic evaluation demonstrated good osseointegration in all but 1 included patient.

CONCLUSION

The utility of custom 3D-printed components for managing severe glenoid bone loss in primary and revision reverse total shoulder arthroplasty yields significant clinical improvements in this complex cohort. Large complex glenoid bone defects can be managed successfully with custom 3D-printed glenoid components.

Anatomical shoulder replacements in young patients: A systematic review and meta-analysis

Introduction

Increasing numbers of young patients receive shoulder replacements. Greater information on outcomes is needed to inform implant choice. The aim of this study was to investigate the survivorship and clinical effectiveness of hemiarthroplasty and anatomical total shoulder arthroplasty (TSA) in patients younger than 65 years.

Method

A systematic review was performed of MEDLINE, EMBASE, CENTRAL, The Cochrane Database of Systematic Reviews and National Joint Registry reports. The primary outcomes were implant survival and change in perioperative shoulder scores.

Results

Meta-analysis of implant survivorship was performed of six studies reporting on 416 patients. Implant survival was 86.1% (72.1,100) at 10 years for hemiarthroplasty and 82.3% (64.6,100) for TSA. 20 year survival was 80.0% for hemiarthroplasty (72.5,87.4) and 75.0% (56.9,93.1) for TSA. Ten studies were included in the meta-analysis of shoulder scores, multiple instruments were used. The standardised mean difference between pre-operative and post-operative shoulder scores was 2.15 (1.95, 2.35) for TSA at 4.2-4.9 years, and 2.72 (1.98,3.47) for hemiarthroplasty at 3.8-6 years.

Conclusion

Over 80% of shoulder replacements last more than 10 years, and 75% last more than 20 years. Significant improvements in shoulder scores are shown at all time points.

Management of glenoid bone loss with impaction and structural bone grafting in reverse shoulder arthroplasty

INTRODUCTION

Glenoid bone loss is a commonly encountered problem in complex primary and revision shoulder arthroplasty. Addressing glenoid bone loss is critical to avoid complications like early loosening, impingement, notching and instability. A large number of techniques like bone grafting using autograft or allograft, eccentric reaming, augmented base plates, patient-specific instrumentations and custom-made implants are available to tackle bone loss.

MATERIALS AND METHODS

We prospectively collected the data of all patients with glenoid defects undergoing primary or revision reverse shoulder replacement between 2004 and 2017. This included demographic data, ranges of motion, Constant-Murley score and Subjective Shoulder Value (SSV). A pre-operative CT scan was done as well to plan the surgery and calculate the glenoid version. At each follow-up, the clinical function and shoulder scores were assessed. Additionally, the radiographs were assessed for graft incorporation, evidence of lysis and calculation of glenoid version.

RESULTS

Between 2004 and 2017, 37 patients underwent glenoid bone grafting during reverse shoulder arthroplasty. Average age was 72 years (range 46-88). Indications for surgery were cuff tear arthropathy (6 patients); revision of failed other prosthesis (23); primary osteoarthritis (4); rheumatoid arthritis (3); and second-stage revision for infection (1). The glenoid defect was contained in 24 patients, and therefore, impaction graft with a combination of bone graft substitute and/or humeral head autograft was performed. In 13 patients the glenoid defect was severe and uncontainable and therefore a graft-implant composite glenoid was implanted using humeral head autograft or allograft. Average follow-up was 3.6 years (range 1-10). Mean Constant score improved from 34 before surgery to 63 after surgery. Mean SSV score improved from 0.9/10 to 8.3/10. Active movements improved significantly with forward elevation increasing from 54° to 123°; abduction from 48° to 123°; external rotation from 24° to 38°; internal rotation from 57° to 70°. Radiographs at final follow-up showed no radiolucencies around the glenoid component and no evidence of loosening of the implant. In 2 cases there was a grade I notching. There was 100% survivorship at the last follow-up.

CONCLUSION

Impaction bone grafting along with structural grafting when required is an effective and reproducible way of managing severe glenoid bone loss. This technique gives consistent and good clinical and radiological results.

Revision of total shoulder arthroplasty to hemiarthroplasty: results at mean 5-year follow-up

BACKGROUND

Although there is a trend to manage failed anatomic total shoulder arthroplasties (aTSA) with revision to a reverse total shoulder arthroplasty, such revisions can be complicated by difficulties in baseplate fixation, instability, and acromial stress fractures. Some cases of failed aTSA may be safely revised to a hemiarthroplasty (HA). The objectives of this study were to report patient-reported outcomes after conversion from aTSA to HA and assess patient and shoulder characteristics associated with a successful outcome.

METHODS

Patients who underwent revision from aTSA to HA between 2009 and 2018 were contacted. Patient demographics, surgical history, intraoperative findings, and microbiology results were collected. Patient-reported outcomes were collected with minimum 2-year follow-up. Preoperative radiographic characteristics were reviewed for component positioning and component loosening. Patients with a clinically significant improvement exceeding the minimal clinically important difference (MCID) of the Simple Shoulder Test (SST) were compared with those patients who did not improve past the MCID.

RESULTS

Twenty-nine patients underwent conversion from aTSA to HA with a mean follow-up of 4.5 ± 1.8 years. Intraoperative glenoid or humeral component loosening was found in all 29 patients. Pain improved in 25 of 30 patients (87%), and mean pain scores improved from 6.2 ± 2.3 to 3.1 ± 2.4 (P < .001). SST scores improved from 4.1 ± 3.1 to 7.3 ± 3.2 (P < .001), and 18 of 29 patients (62%) had improvement above the SST MCID threshold of 2.4. The mean American Shoulder and Elbow Surgeons score at the latest follow-up was 64 ± 19, and the Single Assessment Numeric Evaluation score was 65 ± 23. Twenty-two of 29 (76%) patients were satisfied with the procedure. Four patients (14%) required conversion to total shoulder arthroplasty-2 to anatomic and 2 to reverse. An additional 3 patients (10%) had a revision HA performed. No significant differences in patient or shoulder characteristics were found in those patients who improved greater than the MCID of the SST compared patients who improved less than the MCID of the SST. Fifty-nine percent of patients had ≥2 positive cultures with the same bacteria, and 82% of these were with Cutibacterium. Seven of 8 patients (88%) with a loose humeral component had ≥2 positive cultures with the same bacteria.

DISCUSSION

Component loosening is a common failure mode after aTSA. Revision to HA can improve pain and patient-reported outcomes in most patients.

What is the optimal management of a loose glenoid component after anatomic total shoulder arthroplasty: a systematic review

BACKGROUND

Total shoulder arthroplasty (TSA) provides excellent long-term clinical outcomes in the treatment of glenohumeral arthritis. However, symptomatic glenoid polyethylene loosening can be seen at intermediate follow-up and can lead to shoulder pain and dysfunction. The purpose of this study was to perform a systematic review of the available literature to determine the optimal management of symptomatic glenoid loosening with regard to reoperation and patient satisfaction following various approaches to symptomatic glenoid loosening.

METHODS

This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Studies investigating revision arthroplasty for the treatment of glenoid loosening with clinical outcomes were identified. Clinical failure was defined as a repeat procedure after revision arthroplasty.

RESULTS

Overall, 14 studies met inclusion criteria that included 483 patients with a mean age of 66.5 ± 3.0 years who underwent revision arthroplasty for symptomatic glenoid loosening. There were 8 studies that discussed conversion to a hemiarthroplasty (HA, 148 patients), 7 studies that discussed glenoid reimplantation in a single setting (1-stage TSA, 157 patients), 2 studies that discussed glenoid reimplantation in a staged setting (2-stage TSA, 18 patients), and 2 studies that discussed conversion to a reverse shoulder arthroplasty (RSA, 164 patients). All patients underwent glenoid component removal. The length of follow-up was significantly shorter in the RSA group (41 months for RSA vs. 56 months for HA vs. 55 months for 1-stage TSA vs. 62 months for 2-stage TSA, P < .001). The reoperation rate at the final follow-up was 19% for the HA cohort, 20% for the 1-stage TSA cohort, 22% for the 2-stage TSA cohort, and 21% for the RSA cohort (P = .971). Patient satisfaction rate at the final follow-up was 62% for the HA cohort, 66% for the 1-stage TSA cohort, 71% for the 2-stage TSA cohort, and 86% for the RSA cohort (P = .045). Positive cultures were noted in 15% of patients with Cutibacterium acnes comprising 72% of positive cultures.

CONCLUSIONS

Overall, the optimal management of symptomatic glenoid loosening remains unclear. All 4 types of revision arthroplasty (HA, 1-stage TSA, 2-stage TSA, and RSA) had a similar reoperation rate (20%) at the latest follow-up. Conversion to RSA provided a higher proportion of patients satisfied with the procedure. However, the length of follow-up was significantly shorter than other groups, and therefore longer-term follow-up of this group is needed to determine if results are durable.

A review of custom implants for glenoid bone deficiency in reverse shoulder arthroplasty

Reverse Total Shoulder Arthroplasty is being increasingly performed, with indications in both elective and trauma settings. Accordingly, there are an increasing number of revision cases where glenoid bone loss is a concern. There are well recognised surgical techniques for dealing with mild to moderate glenoid wear, including eccentric reaming and impaction grafting. In cases of severe wear or uncontained glenoid defects these may not be suitable, and the surgeon may look to a customised implant to deal with such bone loss. There are several implant manufacturers who currently market and produce patient specific instrumentation and customised glenoid baseplates to achieve the best possible fixation in cases of severe bone loss. This article outlines some examples of custom implants currently available to surgeons, and the process by which they may be procured and used. Implant and surgical considerations, and key aspects of surgical technique are also covered. Literature on outcomes and complications following custom shoulder arthroplasty shows promising results, but at present is limited to relatively small case series with no long-term outcome data.

[Bony glenoid reconstruction in revision arthroplasty]

Glenoid pathologies are one of the main indications for shoulder arthroplasty revisions. In most cases, the glenoid bone defect is associated with insufficiency of the rotator cuff, so that only reverse total shoulder arthroplasty can be considered as a revision implant. For stable permanent fixation of the reverse glenoid component, to avoid inferior glenoid notching, and to achieve optimal function, physiological restoration of three-dimensional glenoid anatomy is necessary. In order to approach the individual glenoid pathologies in a differentiated and optimal manner, it is important to classify the defects. A basic distinction must be made between centric contained and eccentric uncontained defects. Combinations often occur. It is also important to consider the severity, depth, and three-dimensional orientation of the defect. Therefore, a CT analysis of the glenoid is essential preoperatively. The data obtained should serve as the basis for computer-assisted planning to determine the optimal position of the glenoid baseplate and the type and shape of the bone graft for the reconstruction. For patients with good bone quality, we recommend defect reconstruction with autologous iliac crest. The type of graft configuration and fixation and the decision between a one- and two-stage procedure depend on the type and severity of the defect. With technically correct reconstruction and proper prosthesis implantation, sufficient integration of the bone graft and durable fixation of the glenoid component can be expected with satisfactory clinical results. After bony reconstruction of the defects, repeated treatment with a reverse arthroplasty is possible in the long term in the event of renewed glenoid problems.

Biologic graft augmentation for glenoid bone loss in conversion of failed anatomic to reverse shoulder arthroplasty: a systematic review

Glenoid bone loss presents a challenging dilemma, particularly in the setting of failed arthroplasty requiring conversion to a reverse total shoulder arthroplasty (rTSA). The aim of our systematic review was to examine the success and failure of biologic glenoid bone grafting to address vault deficiencies in the setting of shoulder arthroplasty conversion to rTSA. Twelve articles were included and a complete PUBMED search. Inclusion criteria included glenoid bone grafting for conversion of failed arthroplasty and a minimum of 12 months follow-up. Exclusion criteria included grafting for primary rTSA, and re-revision for infection or humeral loosening. Failures were defined as failure of the graft to radiographically incorporate, symptomatic base plate loosening, and need for further surgical re-revision. Two hundred patients were identified across the 12 articles. Eighteen percent (36/200) of all cases demonstrated failure to radiographically incorporate. Thirteen percent (25/200) of all grafting cases required re-revision due to symptomatic failure (pain or functional deterioration). Femoral shaft demonstrated the highest failure rate at 88% (7/8). Grafting for glenoid bone loss in the setting of conversion to rTSA has an 82% rate of success across autograft and allograft utilization. Further studies are needed to better define the success of autografting versus allografting in the setting of shoulder arthroplasty conversion to rTSA with glenoid bone loss.

[Metal glenoid augmentation in revision arthroplasty]

Glenoid implantation in revision arthroplasty of the shoulder remains a technical challenge in the case of severe bone loss. Metal glenoid augmentation and patient-specific glenoid implants represent new treatment options with great potential. Virtual planning techniques allow a differentiated evaluation of the extent of the bone loss and the planning of different augmentation options. Although not clearly defined so far, a patient-specific implant can be indicated if adequate fixation of the base plate in the native bone appears questionable. The planning is carried out with the support of the prostheses manufacturer and the stability is simulated using finite element analysis. A high level of primary stability is achieved by an optimized fitting of the implant into the bony defect. The short-term results are promising. However, in the absence of long-term results and limited options in case of revision, the use of a custom-made glenoid warrants a strict indication.

[Revision of anatomic shoulder arthroplasty]

With the increasing number of primary arthroplasties, revisions of anatomical prostheses are becoming increasingly important. The most common reasons for revision are glenoid loosening, including protrusion, rotator cuff insufficiency, including instability, and early/late infection. The reconstruction of glenoid defects can be done with an autograft or allograft. Depending on the size and situation, it is carried out in one or two stages. The stemless humeral head replacement and the short-stem prostheses that have been used more frequently in recent years have significantly simplified humeral revision. Platform systems take a different approach with the option of conversion without major interventions on the glenoid or revision stem. Intraoperative complications mainly occur on the humeral side. Postoperative complications include dislocation, component loosening, and infection. Revision of anatomical to reverse arthroplasty shows better clinical outcomes and lower complication rates than anatomical revision.

Clinical and Radiological Outcomes after Total Shoulder Arthroplasty Using Custom-Made Glenoid Components: A Systematic Review

Reverse total shoulder arthroplasty presents itself sometimes as challenging when it comes to addressing massive bone loss, either in primary or revision settings. Custom components recently have made their way into shoulder prosthetics and are meant to help in the case of extensive glenoid bone destruction. Because of strict indication and the fairly recent introduction of these implants, the usage of custom-made glenoid implants is not very common yet. However, the early results are promising. The purpose of this review was to summarize and analyze the available literature. Therefore, a systematic review was performed according to PRISMA guidelines. A comprehensive search of the databases PubMed, Cochrane, and Livivo was performed to screen for studies reporting on clinical and radiological outcomes of custom glenoid implants. Four studies with a total of 46 shoulders were included in this review. The mean patient age was 68.8 years and the mean time of follow-up was 24.3 months. The weighted means showed an increase in CMS (32.7 points), in ASES (39.8 points), in anteversion (67.4 degrees), and in abduction (51.9 degrees) and a decrease in VAS (5.4 points). Custom-made glenoid implants are therefore a viable option in cases of large combined glenoid bone loss, both in primary and revision shoulder arthroplasty.

Management of glenoid bone loss in primary reverse shoulder arthroplasty

Aims

Rates of reverse total shoulder arthroplasty (rTSA) continue to grow. Glenoid bone loss and deformity remains a technical challenge to the surgeon and may reduce improvements in patients’ outcomes. However, there is no consensus as to the optimal surgical technique to best reconstruct these patients’ anatomy. This review aims to compare the outcomes of glenoid bone grafting versus augmented glenoid prostheses in the management of glenoid bone loss in primary reverse total shoulder arthroplasty.

Methods

This systematic review and meta-analysis evaluated study-level data in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. We performed searches of Medline (Ovid), Embase (Ovid), and PubMed from their dates of inception to January 2022. From included studies, we analyzed data for preoperative and postoperative range of motion (ROM), patient-reported functional outcomes, and complication rates.

Results

A total of 13 studies (919 shoulders) were included in the analysis. The mean age of patients at initial evaluation was 72.2 years (42 to 87), with a mean follow-up time of 40.7 months (24 to 120). Nine studies with 292 rTSAs evaluated the use of bone graft and five studies with 627 rTSAs evaluated the use of augmented glenoid baseplates. One study was analyzed in both groups. Both techniques demonstrated improvement in patient-reported outcome measures and ROM assessment, with augmented prostheses outperforming bone grafting on improvements in the American Shoulder and Elbow Surgeons Score. There was a higher complication rate (8.9% vs 3.5%; p < 0.001) and revision rate among the bone grafting group compared with the patients who were treated with augmented prostheses (2.4% vs 0.6%; p = 0.022).

Conclusion

This review provides strong evidence that both bone graft and augmented glenoid baseplate techniques to address glenoid bone loss give excellent ROM and functional outcomes in primary rTSA. The use of augmented base plates may confer fewer complications and revisions. Cite this article: Bone Joint J 2022;104-B(12):1334–1342.

Clinical results and 10-year survivorship of the Synthes Epoca resurfacing total shoulder arthroplasty

Aims

This prospective cohort study reports the 10-year survivorship, patient-reported outcome measures and radiographic outcomes of the first series of the Epoca resurfacing head total shoulder arthroplasty.

Methods

From July 2008 to July 2014, 59 Epoca resurfacing head total shoulder arthroplasties were implanted in 50 patients by a single surgeon. Minimum 4.8 year and maximum 11.3 year follow-up (mean: 7.9 years) was analysed using the latest available Oxford Shoulder Score. Kaplan-Meier survivorship analysis was performed with revision as the end point. Most recent radiographs were reviewed for component radiolucency, osteolysis and proximal humeral migration.

Results

Two shoulders underwent revision (3.4%); one for pain with posterior subluxation following a fall, the other for pain with failure of the glenoid. Kaplan-Meier analysis revealed 10-year survivorship of 98.2% (95% confidence intervals: 88.0%-99.8%). Mean Oxford Shoulder Score improved significantly compared to pre-operative values from 18.2 (5-45) to 46.6 (36-48) (p < 0.001). Fifty-three shoulders underwent radiographic analysis (89.8%). This revealed humeral radiolucency in two cases (3.8%), glenoid radiolucency in three cases (5.7%) and radiographic rotator cuff failure in eight cases (15.1%).

Conclusion

This prospective cohort study shows excellent 10-year survivorship, medium to long-term clinical and radiological results and for the Synthes Epoca resurfacing head total shoulder arthroplasty.

Evidence level

IV.

Temporary Protective Shoulder Implants for Revision Surgery with Bone Glenoid Grafting

This article describes the development of a temporary protective glenoid prosthesis placed between the augmentation and humeral head prosthesis during the healing phase of shoulder prosthesis revision with necessary reconstruction of the bony structure of the glenoid. The glenoid protection prosthesis ensures the fixation of the augmentation material and protects the screws from contact with the metallic humeral head prosthesis. Another approach of the development is a reduction of the resorption of the augmentation by targeted mechanical stimulation of the tissue. The aim should be to achieve significantly improved conditions for the implantation of a new glenoid component at the end of the healing phase of the augmentation material in comparison to the current standard method. The development of the protective prosthesis was carried out according to specific needs and includes the collection of requirements and boundary conditions, the design and technical detailing of the implant, the verification of the development results as well as the validation of the design. For the verification, FEM simulations (Finite Element Analysis) were performed to estimate the mechanical stability in advance. Mechanical tests to confirm the stability and abrasion behavior have been carried out and confirm the suitability of the protective implant. The result of the present work is the detailed technical design of two variants of a glenoid protective prosthesis "GlenoProtect" for use in revision procedures on shoulder joints-with large-volume defects on the glenoid-treated by arthroplasty and the necessity of augmenting the glenoid, including a description of the surgical procedure for implantation.

Hemi-reverse revision arthroplasty in the setting of severe glenoid bone loss

BACKGROUND

Glenoid bone loss is one of the main challenges in revision of failed shoulder arthroplasties. The concept of a hemi-reverse procedure is to implant a glenoid baseplate and glenosphere to protect the glenoid reconstruction to allow it to heal and to preserve the joint space for a potential second-stage humeral component implantation. The purpose of this study was to report the results of hemi-reverse procedures.

METHODS

Revision to a hemi-reverse procedure was performed in 15 patients: 8 with a failed anatomic total shoulder arthroplasty, 3 with a failed reverse shoulder arthroplasty, 3 with a failed humeral hemiarthroplasty, and 1 with placement of a cement spacer owing to sepsis after a total shoulder arthroplasty. After complete removal of the initial prosthesis, all patients underwent glenoid reconstruction with bone grafting and implantation of a reverse arthroplasty baseplate and glenosphere. A humeral implant was not placed in any case. The patients were prospectively followed up and underwent complete clinical and radiologic studies preoperatively and postoperatively at a minimum of 2 years after the surgical procedure.

RESULTS

Thirteen hemi-reverse implants and glenoid bone grafts healed (86%) and remained radiographically stable. One hemi-reverse construct migrated and became mechanically loose, which was attributed to absent fixation of the central post in the native glenoid bone. In 1 patient, an implant-related infection developed; irrigation and debridement were performed, in addition to revision to a resection arthroplasty. After documented radiographic healing of the hemi-reverse glenoid reconstruction, 5 patients underwent a second-stage revision to a reverse procedure with insertion of a humeral component at a median of 6 months (interquartile range [IQR], 6-8 months). In this group, the median follow-up period was 73 months (IQR, 45-153 months), the median Constant score was 48 (IQR, 41-56), median active forward elevation was 135° (IQR, 100°-150°), and the median Subjective Shoulder Value was 50% (IQR, 50%-60%). In the group of 9 patients with remaining hemi-reverse implants, the median follow-up period was 38 months (IQR, 29-60 months), the median Constant score was 41 (IQR, 38-46), median active forward elevation was 100° (IQR, 80°-100°), and the median Subjective Shoulder Value was 50% (IQR, 40%-60%).

CONCLUSION

The hemi-reverse procedure is an effective revision procedure to reconstruct a severely deficient glenoid. The hemi-reverse procedure may function as the definitive procedure, with satisfactory outcomes. Additionally, in patients who undergo the hemi-reverse procedure, second-stage revision to a total reverse procedure can be performed once imaging confirms bone graft and construct stability.

The fifty most cited publications in shoulder arthroplasty research

INTRODUCTION

Frequency of citation provides one quantitative metric of the impact that an article has on a given field. The purpose of this study was to evaluate characteristics of the 50 most cited publications on shoulder arthroplasty.

METHODS

The Web of Science database was used to determine the 50 most frequently cited shoulder arthroplasty articles. Articles were evaluated for several factors including type of arthroplasty, citation frequency and rate, source journal, country of origin, study type, and level of evidence.

RESULTS

The most common countries of origin were the United States (60%) followed by France (24%) and Switzerland (6%). A total of 27 (54%) articles included anatomic total shoulder arthroplasty (TSA), 18 (36%) included reverse total shoulder arthroplasty (RTSA), and 15 (30%) included hemiarthroplasty. Articles including RTSA had the greatest number of citations compared to those on TSA (p = 0.037) and hemiarthroplasty (p = 0.035). Citations per year were also greatest with RTSA compared to TSA and hemiarthroplasty (p ≤ 0.001).

DISCUSSION

This citation analysis includes many of the landmark studies that shaped, and continue to impact, the field of shoulder arthroplasty. This list provides a group of influential articles that provide a foundation for future research in shoulder arthroplasty.

Assessing the required glenoid peg penetration in native scapula when bone graft is used during primary and revision shoulder arthroplasty

AIMS

Achieving purchase in native glenoid bone is essential for the stability of the glenoid baseplate when bone graft is used to address bone loss in both primary and revision shoulder arthroplasty procedures. The aim of this study is to assess the required depth of the baseplate peg in native bone when bone graft is used to result in satisfactory integration.

PATIENTS AND METHODS

The CT scans of patients who underwent either primary or revision arthroplasty procedures with bone graft using the SMR Axioma Trabecular Titanium (TT) Metal Backed glenoid system were assessed. We measured the depth of the glenoid peg in native glenoid bone. Measurements were taken by two authors separately.

RESULTS

The scans of 53 patients (mean age 68 years) with a minimum follow-up of two years were reviewed. Implants included 12 anatomical and 41 reverse geometry prostheses. There were 17 primaries and 36 revisions: hemiarthroplasties (20) total (14) and reverse (2) implants. Bone grafts were from humeral head (15), iliac crest (34) and allograft (4). The mean depths were 8.8 mm (first assessor) and 9.10 mm (second assessor). The glenoid peg violated the glenoid vault in 32 patients and this did not adversely affect the outcome. There were three failures of implants all of which were aseptic failures and had peg penetration of less than 6 mm.

CONCLUSIONS

The mean depth of glenoid peg in native bone was 9 mm (variation between 0.2 and 0.52 mm at 95% confidence interval). Aseptic loosening was seen with peg penetration less than 6 mm in native bone. Glenoid vault violation was not associated with loosening.

Identifying areas of screw fixation in glenoids with severe bone loss in shoulder arthroplasty

BACKGROUND

Severe glenoid bone loss (SGBL) poses significant technical challenges. Adequate fixation of glenoid implants may require the use of alternative screw placement. Although bone volumes for the spine and lateral pillars have previously been defined, insufficient evidence exists regarding the distribution of screw placement for fixation in such regions for cases with SGBL. The purpose of this study is to evaluate the variability of screw placement. We hypothesize that determining this variability and establishing common patterns of glenoid bone loss will allow for recommendations for preoperative planning, and implant design and selection.

METHODS

An internal registry of 2 high-volume shoulder and elbow surgeons was queried, and 65 three-dimensional scapulae models exhibiting SGBL were identified. A fellowship-trained shoulder and elbow surgeon simulated the placement of two 3.5 mm × 30 mm screws, one in the scapular spine (CS) bone volume and one in the inferior column (IS) bone volume. Three orthogonal reference planes were created using anatomic reference points: the scapula trigonum, estimated glenoid center, and inferior pole. Screw positions were mapped, and deviations from the reference planes were calculated. Mutual positions of the IS to CS were also computed. Intraobserver reliability was assessed using 10 randomly selected samples. Median and 25th and 75th percentiles were reported for screw orientation distributions. Means and standard deviations were reported for screw head positions.

RESULTS

We demonstrated excellent intraobserver reliability (intraclass correlation coefficients, 0.90-0.98). Fifty percent of CS were oriented 10° ± 5° of retroversion from the scapula plane, with 5° ± 5° of inclination. For IS, 50% were positioned 0° ± 4° from the scapula plane, with -33° ± 7° of inclination. The relationship of the IS with the CS was medial and posterior in 49% of cases, lateral and posterior in 45%, and lateral and anterior in 6% of cases. On average, the distance between the CS and IS heads was 25 mm ± 4 mm.

DISCUSSION

For SGBL, adequate fixation of glenoid implants can be achieved by placing screws in the spine and lateral columns, with excellent reproducibility. Future implant designs should accommodate CS positioned -16° to -5° from the scapula plane, with 0° to 12° of inclination, and IS positioned -6° to 4° from the scapula plane, with -40° to -25° of inclination. Moreover, mutual screw positions suggested bone loss distributions anteriorly and inferiorly. Future implant designs should consider the potential benefits of augmentation to accommodate interscrew distances of 21-29 mm and anatomic locations of the IS relative to the CS.

The Y plane is a reliable CT-based reference for glenoid component positioning in shoulder arthroplasty

Purpose

To determine the reliability of anatomic references for mediolateral component positioning in shoulder arthroplasty.

Materials and methods

The computed tomography scans of 86 shoulders free of arthritic or anatomic deformities were studied. Two surgeons independently digitized a series of points, including the intersection of the 3 bone branches of the scapular spine (Y), the center of the glenoid surface (G), the most medial point of the scapula (MS), the cortical convergence (CC) of the anterior and posterior margins of the glenoid, the base of the coracoid (BC), the anterior (HA) and posterior (HP) margins of the subchondral bone.

Results

The mean mediolateral distances between G and Y, BC, CC were respectively − 19.6 mm, − 1.5 mm, and − 36.8 mm. The consistency of anatomic landmarks was greatest for Y (standard deviation (SD) =2.3 mm; interquartile range (IQR) =3 mm), compared to BC (SD = 4.6 mm; IQR = 7 mm), and CC (SD = 6.6 mm; IQR = 8 mm). The repeatability of anatomic landmarks was excellent for all measurements. The mean ratios (relative to humeral head size) of distances between G and Y, BC, CC were respectively − 0.45, − 0.04, and − 0.85. The consistency of ratios was greatest for Y (SD = 0.05; IQR = 0.06), compared to BC (SD = 0.11; IQR = 0.14), and CC (SD = 0.13; IQR = 0.17). The repeatability of ratios was excellent for Y and BC, while it was good for CC.

Conclusions

The Y-plane is a reliable reference for glenoid component positioning in shoulder arthroplasty, with a consistent distance from the center of the glenoid surface, and could therefore be suitable for preoperative planning.

Study design

Level III, comparative anatomic study.

Anatomic Total Shoulder Arthroplasty: Component Size Prediction with 3-Dimensional Pre-Operative Digital Planning

Background

The rate, complexity, and cost of total shoulder arthroplasty (TSA) continues to grow. Technology has advanced pre-operative templating. Reducing cost of TSA has positive impact for the patient, manufacturer, and hospital. The aim of this study was to evaluate the accuracy of implant size selection based on 3-D templating. Our hypothesis was that pre-operative templating would enable accurate implant prediction within one size.

Methods

Multicenter retrospective study of anatomic TSAs templated utilizing 3-D virtual planning technology. This program uses computed tomography (CT) scans allowing the surgeon to predict component sizes of the glenoid and humeral head and stem. Pre-operative templated implant size were compared to actual implant size at the time of surgery. Primary data analysis utilized unweighted Cohen's Kappa test.

Results

111 TSAs were analyzed from five surgeons. Pre-operative templated glenoid sizes were within one size of actual implant in 99% and exactly matched in 89%. For patients requiring a posterior glenoid augment (n = 14), 100% of implants were within one size of the template and 93% matched exactly. For stemless humeral components (n = 87) implanted, 98% matched the pre-operative template within one size with 79% exactly matched. For stemmed components (n = 24), 88% of cases were within one size of the preoperative plan and exactly matching in 83%. Humeral head diameter matched within one size of the pre-operative template in 84% of cases and exactly matched in 72%.

Conclusion

Pre-operative 3-D templating for TSAs can accurately predict glenoid and humeral component size. This study sets the groundwork for utilization of pre-operative 3-D templating as a potential method to reduce overall TSA costs by managing cost of implants, reducing inventory needs, and improving surgical efficiency.

Targeting repeatability of a less obtrusive surgical navigation procedure for total shoulder arthroplasty

PURPOSE

Surgical navigation systems have demonstrated improvements in alignment accuracy in a number of arthroplasty procedures, but they have not yet been widely adopted for use in total shoulder arthroplasty (TSA). We believe this is due in part to the obtrusiveness of conventional optical tracking systems, as well as the need for additional intraoperative steps such as calibration and registration. The purpose of this study is to evaluate the feasibility of adapting a less-intrusive dental navigation system for use in TSA.

METHODS

We developed a proof-of-concept system based on validated laser-engraved surgical tools recently introduced for use in dental surgery that are calibrated once when manufactured and not recalibrated at time of use. The design also features a notably smaller bone-mounted tracker that can be tracked from a wide range of viewing angles. To assess our system's performance, we modified the dental surgical software to support guidance of a TSA procedure. We then conducted a user study in which three participants with varying surgical experience used the system to drill 30 holes in a glenoid model. Using a coordinate measuring machine, we determined the resulting drilled trajectory and compared this to the pre-planned trajectory. Since we used a model glenoid rather than anatomical specimens, we report on targeting precision rather than overall procedure precision or accuracy.

RESULTS

We found targeting precision < 1 mm (standard deviation) for locating the entry hole and <  ~ 1° (SD) for both version and inclination. The latter value was markedly lower than the end-to-end angular precision achieved by previously reported TSA navigation systems (approximately 3°-5° SD).

CONCLUSION

We conclude that variability during the targeting phase represents a small fraction of the overall variability exhibited by existing systems, so a less obtrusive navigation system for TSA based on laser-engraved tooling is likely feasible, which could improve the uptake rates of surgical navigation for TSA, thereby potentially leading to improved overall surgical outcomes.

Management of Humeral and Glenoid Bone Defects in Reverse Shoulder Arthroplasty

Bone loss of either the glenoid or the humerus is a challenging problem in reverse total shoulder arthroplasty. When left unaddressed, it can lead to early failure of the implant and poor outcomes. Humeral bone loss can be addressed with the use of an endoprosthesis or allograft prosthetic implant. Glenoid bone loss can be treated with a variety of grafting options, such as augmented implants, patient-specific navigation, and implantation systems.

Outcome and complications following revision shoulder arthroplasty : a systematic review and meta-analysis

AIMS

It is important to understand the rate of complications associated with the increasing burden of revision shoulder arthroplasty. Currently, this has not been well quantified. This review aims to address that deficiency with a focus on complication and reoperation rates, shoulder outcome scores, and comparison of anatomical and reverse prostheses when used in revision surgery.

METHODS

A Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) systematic review was performed to identify clinical data for patients undergoing revision shoulder arthroplasty. Data were extracted from the literature and pooled for analysis. Complication and reoperation rates were analyzed using a meta-analysis of proportion, and continuous variables underwent comparative subgroup analysis.

RESULTS

A total of 112 studies (5,379 shoulders) were eligible for inclusion, although complete clinical data was not ubiquitous. Indications for revision included component loosening 20% (601/3,041), instability 19% (577/3,041), rotator cuff failure 17% (528/3,041), and infection 16% (490/3,041). Intraoperative complication and postoperative complication and reoperation rates were 8% (230/2,915), 22% (825/3,843), and 13% (584/3,843) respectively. Intraoperative and postoperative complications included iatrogenic humeral fractures (91/230, 40%) and instability (215/825, 26%). Revision to reverse total shoulder arthroplasty (TSA), rather than revision to anatomical TSA from any index prosthesis, resulted in lower complication rates and superior Constant scores, although there was no difference in American Shoulder and Elbow Surgeons scores.

CONCLUSION

Satisfactory improvement in patient-reported outcome measures are reported following revision shoulder arthroplasty; however, revision surgery is associated with high complication rates and better outcomes may be evident following revision to reverse TSA. Cite this article: Bone Jt Open 2021;2(8):618-630.

Trends and impact of three-dimensional preoperative imaging for anatomic total shoulder arthroplasty

BACKGROUND

The goals of this study were to determine the incidence in the United States of preoperative three-dimensional imaging prior to anatomic total shoulder arthroplasty for osteoarthritis and to determine if preoperative imaging is associated with decreased complication rates.

METHODS

Using a Medicare insurance database, we identified all patients who underwent computed tomography (n = 9380) and/or magnetic resonance imaging (n = 15,653) prior to anatomic total shoulder arthroplasty for a diagnosis of osteoarthritis from 2005 to 2014. The incidence of imaging over time was analyzed and complication rates compared between patients with imaging to matched controls.

RESULTS

The incidence of preoperative three-dimensional imaging significantly increased over time, with computed tomography increasing more than magnetic resonance imaging. Compared to controls, patients with preoperative computed tomography imaging had significantly lower revision rates at two years (odds ratio 0.72 (0.64-0.82), p = 0.008). There were no other significant differences in the other complications studied.

CONCLUSIONS

The use of preoperative three-dimensional imaging for anatomic total shoulder arthroplasty for a diagnosis of osteoarthritis has increased dramatically, with the use of computed tomography increasing the most. Patients who underwent preoperative computed tomography imaging experienced lower revision rates at two years postoperatively compared to matched controls without such imaging.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Is bone grafting always necessary in revision reverse total shoulder arthroplasty with uncontained glenoid bone defects?

BACKGROUND

Patients with an uncontained glenoid bone defect can still successfully undergo a reverse total shoulder arthroplasty (RTSA). Currently, there is a tendency toward reconstruction of the premorbid glenoid plane with bone grafts, which is technically demanding. We investigated whether central peg positioning in the spine pillar (CPPSP) is a more feasible alternative to the use of bone grafts.

METHODS

This study included 60 revisions to an RTSA with uncontained glenoid bone defects. Patients were treated with bone grafts in 29 cases and with the CPPSP technique in 31 cases. We assessed clinical results using the Constant score and assessed the complication rate.

RESULTS

The Constant score changed from 42 to 69 points in the CPPSP group and from 47 to 60 points in the bone graft group. This difference in the increase in the Constant score was significant (P = .031) owing to a significant difference in strength in favor of the CPPSP group. The overall complication rate was 37.7% (20 of 53 patients), with a reoperation rate of 18.9% (10 of 53). Dislocations occurred only in the CPPSP group (n = 3), and loosening of the glenoid occurred only in the bone graft group (n = 3).

CONCLUSION

Patients with uncontained glenoid bone defects undergoing revision to an RTSA obtain similar clinical results with the CPPSP technique compared with the use of bone grafts. The CPPSP technique is a valid alternative but results in different complications.

Incidence of peripheral nerve injury in revision total shoulder arthroplasty: an intraoperative nerve monitoring study

BACKGROUND

The incidence of nerve injuries in revision total shoulder arthroplasty (TSA) is not well defined in the literature and may be higher than that in primary procedures, with 1 study reporting a complication rate of 50% for shoulder revisions. Given that continuous intraoperative nerve monitoring (IONM) can be an effective tool in diagnosing evolving neurologic dysfunction and preventing postoperative injuries, the purpose of this study was to report on IONM data and nerve injury rates in a series of revision TSAs.

METHODS

A retrospective cohort review of consecutive patients who underwent revision TSA was performed from January 2016 to March 2020. Indications for revision included infection (n = 7); failed total arthroplasty and hemiarthroplasty secondary to pain, dysfunction, and/or loose components (n = 36); and periprosthetic fracture (n = 1). Of the shoulders, 32 underwent revision to a reverse TSA, 6 underwent revision to an anatomic TSA, and 6 underwent spacer placement. IONM data included transcranial electrical motor evoked potentials (MEPs), somatosensory evoked potentials, and free-run electromyography. The motor alert threshold was set at ≥80% signal attenuation in any peripheral nerve. Patients were screened for neurologic deficits immediately following surgery, prior to administration of an interscalene nerve block, and during the first 2 postoperative visits. Additional data collection included surgical indication, sex, laterality, age at surgery, procedure performed, body mass index, history of tobacco use, Charlson Comorbidity Index, medical history, and preoperative range of motion.

RESULTS

A total of 44 shoulders in 38 patients were included, with a mean age of 63.2 years (standard deviation, 13.0 years). Of the procedures, 22.4% (n = 10) had an MEP alert, with 8 isolated to a single nerve (7 axillary and 1 radial) and 1 isolated to the axillary and musculocutaneous nerves. Only 1 patient experienced a major brachial plexus alert involving axillary, musculocutaneous, radial, ulnar, and median nerve MEP alerts, as well as ulnar and median nerve somatosensory evoked potential alerts. Age, sex, body mass index, Charlson Comorbidity Index, and preoperative range of motion were not found to be significantly different between cases in which an MEP alert occurred and cases with no MEP alerts. In the postoperative period, no minor or major nerve injuries were found whereas distal peripheral neuropathy developed in 4 patients (9.1%).

CONCLUSION

Among 44 surgical procedures, no patients (0%) had a major or minor nerve injury postoperatively and 4 patients (9.1%) complained of distal peripheral neuropathy postoperatively. In this study, we have shown that through the use of IONM, the rate of minor and major nerve injuries can be minimized in revision shoulder arthroplasty.

Locked fracture dislocations of the proximal humerus: postoperative results and a proposed modification of the classification

Background

Locked dislocations of the glenohumeral joint are disabling and often painful conditions and the treatment is challenging. This study evaluates the functional outcome and the different prosthetic treatment options for chronic locked dislocations of the glenohumeral joint and a subclassification is proposed.

Methods

In this single-center retrospective case series, all patients with a chronic locked dislocation treated surgically during a four-year period were analyzed. Constant score (CS), Quick Disabilities of Shoulder and Hand Score (DASH), patient satisfaction (subjective shoulder value (SSV)), revision rate and glenoid notching were analyzed.

Results

26 patients presented a chronic locked dislocation of the glenohumeral joint. 16 patients (62%) with a mean age of 75 [61–83] years were available for follow-up at 24 ± 18 months. CS improved significantly from 10 ± 6 points to 58 ± 21 points (p < 0.0001). At the final follow-up, the mean DASH was 27 ± 23 and the mean SSV was 58 ± 23 points. The complication rate was 19% and the revision rate was 6%; implant survival was 94%. Scapular notching occurred in 2 (13%) cases (all grade 1).

Conclusion

With good preoperative planning and by using the adequate surgical technique, good clinical short-term results with a low revision rate can be achieved. The authors suggest extending the Boileau classification for fracture sequelae type 2 and recommend using a modified classification to facilitate the choice of treatment as the suggested classification system includes locked posterior and anterior dislocations with and without glenoid bone loss.

Level of evidence:

IV.

Revision Reverse Shoulder Arthroplasty for Anatomical Glenoid Component Loosening Was Not Universally Successful: A Detailed Analysis of 127 Consecutive Shoulders

BACKGROUND

Glenoid component loosening is a primary cause of failure of anatomical total shoulder arthroplasty (TSA) and is commonly associated with glenoid bone loss. The purpose of the present study was to evaluate the outcome and survival following revision to a reverse total shoulder arthroplasty (RSA) for the treatment of loosening of a polyethylene cemented glenoid component in the setting of failed TSA.

METHODS

Between 2010 and 2017, 151 shoulders underwent revision to RSA for the treatment of loosening of an anatomical polyethylene glenoid component. Shoulders with staged reconstruction for the treatment of infection were excluded. One hundred and twenty-seven patients (67 women and 60 men) had a single-stage reconstruction and were available for follow-up. The mean age at the time of surgery was 70 years (range, 41 to 93 years). In all cases, the humeral component was revised and a standard glenoid baseplate was utilized. Bone graft was used at the discretion of the treating surgeon. Medical records and radiographs were reviewed to collect demographic, intraoperative, and postoperative data; to quantify glenoid bone loss; and to determine the radiographic outcome. The mean duration of follow-up was 35 months (range, 24 to 84 months).

RESULTS

Revision to RSA resulted in significant improvements in terms of pain and motion. Sixteen shoulders (13%) underwent revision surgery for the treatment of baseplate loosening. Radiographic baseplate loosening was present in 6 additional shoulders (overall rate of baseplate loosening, 17%). Intraoperative fracture or fragmentation of the greater tuberosity occurred in 30 shoulders (24%). Other reoperations included resection for deep infection (3 shoulders), arthroscopic biopsies for unexplained persistent pain (2 shoulders), humeral tray exchange for dislocation (2 shoulders), revision for humeral loosening (1 shoulder), irrigation and debridement for hematoma (1 shoulder), and internal fixation of periprosthetic fracture (1 shoulder) (overall reoperation rate, 20%). Among shoulders with surviving implants at the time of the most recent follow-up, pain was rated as none or mild in 83 shoulders (65.4%) and the average active elevation and external rotation were 132° and 38°, respectively. With the numbers available, no risk factors for failure could be identified.

CONCLUSIONS

Revision RSA for the treatment of loosening of an anatomical polyethylene component was associated with a 17% glenoid mechanical failure rate. Although this procedure resulted in improvements in terms of pain and function, it was not universally successful and thus needs further refinement in order to improve outcomes.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Short-term outcomes of reverse shoulder arthroplasty using a custom baseplate for severe glenoid deficiency

HYPOTHESIS AND BACKGROUND

Complex glenoid bone loss and deformity present a challenge for the shoulder arthroplasty surgeon. Eccentric reaming, bone grafting, augmented glenoid components, and salvage hemiarthroplasty are common strategies for managing these patients. The glenoid vault reconstruction system (VRS; Zimmer-Biomet) is a novel solution for both primary and revision arthroplasty using a custom glenoid baseplate. We hypothesized that patients undergoing reverse shoulder arthroplasty (RSA) with VRS would have acceptable short-term outcomes and complication rates.

METHODS

Patients who underwent RSA with VRS for severe glenoid deformity or bone loss by one of 4 board-certified, fellowship-trained shoulder and elbow surgeons at 3 academic tertiary referral centers between September 2015 and November 2018 were eligible for inclusion. Patient data were obtained via medical record review and telephone questionnaires. The Numeric Pain Rating Scale (NPRS), Single Assessment Numeric Evaluation (SANE), American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), Penn Shoulder Scores, and range of motion (ROM) measurements were obtained pre- and postoperatively. Radiographs were reviewed at final follow-up for evidence of component loosening or hardware failure. Any complication was documented. Outcomes were compared using Wilcoxon signed-rank tests with P <. 05 considered significant.

RESULTS

Twelve shoulders (11 patients) were included with a mean age of 68 years; 7 were primary arthroplasties and 5 were revisions. At an average follow-up time of 30 months, median improvement in NPRS score was 7 points, SANE score 43%, ASES score 45 points, and Penn Shoulder Score 49 points. There were statistically significant improvements in median ROM measurements (forward elevation 20°, external rotation 40°, internal rotation 2 spinal levels). At final follow-up, all implants were radiographically stable without loosening. There were no complications.

DISCUSSION AND CONCLUSION

This study demonstrates that RSA using the custom VRS glenoid implant is a safe and effective technique addressing complex glenoid deformity or bone loss in both primary and revision settings. At short-term follow-up, all patient-reported outcomes and ROM measures improved significantly, and there were no complications. Future work should determine mid- and long-term outcomes, preferably in a prospective manner with defined patient populations.

Analysis of revision shoulder arthroplasty in the German nationwide registry from 2014 to 2018

Background

The purpose of this study is to identify and analyze primary revision arthroplasties of the shoulder in the Germany Shoulder Arthroplasty Registry. The objective is to provide demographic and clinical data of the included cases and information about the revision surgery itself and to compare the findings to other registry studies and clinical studies.

Methods

All documented cases of primary revision arthroplasties of the Germany Shoulder Arthroplasty Registry in the time period 2014-2018 (n = 975) were included in the initial data analysis. Exclusion criteria were multiple revisions and data sets with a missing link of the revision arthroplasty to the data set of the primary implantation leaving n = 433 cases that were included. SPSS software (IBM SPSS Statistics for Windows, version 24.0; IBM Corp., Armonk, NY, USA) was used for statistical analyses.

Results

The age of patients with revised anatomic implants (66.3 years) was significantly lower than that of patients with reverse implants (77.1 years) (P = .001). Female patients with anatomic and fracture implants were significantly older than their male counterparts (70.1 vs. 60.5 years, P = .001; 74.3 vs. 62 years, P = .019) and showed a significantly higher rate of revision than their male counterparts (P = .001). The reason for revision was significantly different for anatomic and reverse implant systems (P = .001). Aseptic loosening of either the humeral or glenoid component was the most common reason for revision for anatomic implants, whereas unspecified reasons, dislocation, and loosening of the glenosphere were the most common reasons for reverse implants. The most common type of revision procedure for anatomic implants was conversion to a reverse system in about one third of the cases. Most of the revisions of reverse implants were not specified and almost equally distributed for revision at the humeral or the glenoid side. Anatomic implants showed significantly better Constant-Murley scores (26.1 points) than reverse implants (19.6 points) (P = .001) and significantly better function before revision for passive flexion (P = .002), passive abduction (P = .015), active external rotation (P = .002), and passive external rotation (P = .002).

Conclusion

This study provides a well-documented basis to compare revision arthroplasties of the shoulder performed in Germany over the last decade as documented in the nationwide registry with other nationwide registries and with clinical studies. Especially, the detailed analysis of intraoperative and postoperative complications and the shoulder function at the time of revision offers new information in addition to the results of other registries.

Custom-made reverse shoulder arthroplasty for severe glenoid bone loss: review of the literature and our preliminary results

The treatment of severe glenoid bone loss in shoulder arthroplasty represents a challenge, and the results of current prosthetic designs with only glenoid fixation still remain unsatisfactory. In the past decade, customized glenoid prostheses have been developed to address severe glenoid arthritis and in the revision setting. In this review, we analyzed the current surgical options, the classification limits, past literature evidence, and our preliminary results of 6 patients (3 male, 3 female) treated with a reverse implant and custom-made glenoid implant (ProMade; LimaCorporate, Italy). Computer analysis of the residual shape and the amount of glenoid bone stock in association with new classifications could help the surgeon to obtain good clinical and radiological outcomes. The development of navigation systems could improve the adequacy of the implant and, thus, the reliability and longevity of the implant itself.

Shoulder arthroplasty for juvenile idiopathic arthritis

There is limited literature to guide shoulder surgeons in the management of juvenile idiopathic arthritis (JIA). We aim to help clinicians to formulate an approach to the surgical management of the condition through a review of the available literature on arthroplasty in JIA, general considerations when operating on patients with inflammatory arthropathy and recommendations based on the authors' experience. Four articles report formal data on arthroplasty in JIA with favourable improvements in post-operative pain and function scores after the long-term follow-up. Significant heterogeneity in treatment and a lack of standardisation in quantitative outcomes highlights the need for further larger scale and higher quality research. The aim of this study is to review the evidence and provide information on preoperative evaluation of surgical candidates, operative techniques, choice of implant design and to evaluate functional outcomes in patients who undergo shoulder arthroplasty.

Risk Factors for Re-Revision Surgery in Shoulder Arthroplasty

INTRODUCTION

Revision shoulder arthroplasty is an expensive undertaking with notable morbidity to the patient and less predictable outcomes. Therefore, it is important to avoid even further surgery in these patients. We sought to report the annual revision burden from a large integrated healthcare system and identify patient and operative factors that may predispose patients to revision failure, necessitating further surgery.

METHODS

Annual revision burden as a proportion of the overall shoulder arthroplasties performed from 2005 to 2017 was obtained. Patients who underwent aseptic revision between 2005 and 2017 comprised the study sample. Patient characteristics evaluated for re-revision risk included age, sex, body mass index (BMI), race, and diabetes status, whereas surgical characteristics included surgeon cumulative revision volume, revision procedure type, and top reason for revision by primary procedure type. Multivariable Cox proportional hazards regression was used to evaluate the association between the specified factors and re-revision risk.

RESULTS

From 2005 to 2017, revisions represented 5.3% to 7.8% of all shoulder arthroplasty procedures performed. Factors associated with re-revision surgery risk by procedure type included increasing BMI and hemiarthroplasty revision procedure compared with reverse total shoulder arthroplasty (RTSA) revision procedure for hemiarthroplasty primaries; diabetes, revision because of instability, and lower cumulative surgeon revision procedure volume for RTSA primaries; and TSA revision procedure compared with RTSA revision procedure for TSA primaries.

CONCLUSION

The annual revision shoulder arthroplasty volume increased over the study period. Patient factors, including BMI and diabetes were associated with higher re-revision risks for hemiarthroplasty and RTSA primaries, respectively. RTSA revised for instability had a higher risk of re-revision compared with other indications. TSA and hemiarthroplasty requiring aseptic revision may be best treated with RTSA as opposed to another TSA or hemiarthroplasty. Further studies are needed to verify these findings and identify how the mechanism of failure may affect the procedure selection in the revision setting.

LEVEL OF EVIDENCE

Level III.

Outcomes of Posterior Glenoid Bone-Grafting in Anatomical Total Shoulder Arthroplasty: A Systematic Review

BACKGROUND

Total shoulder arthroplasty offers a reliable means with which to treat glenohumeral joint arthritis. Posterior glenoid bone loss presents a unique challenge with an increased risk of glenoid component failure. The use of posterior bone-grafting is one method to address glenoid bone loss in patients undergoing anatomical total shoulder arthroplasty. The purpose of the present study was to assess the outcome and survival of the glenoid component following the use of bone graft to address posterior glenoid bone loss in patients undergoing anatomical total shoulder arthroplasty.

METHODS

A systematic review of posterior glenoid bone-grafting in patients undergoing anatomical total shoulder arthroplasty was performed. Studies evaluating patient-reported outcomes, complications, and imaging assessments of the glenoid component as well as of bone graft structural healing and integrity following posterior glenoid bone-grafting were included. Data extracted included demographic characteristics, Walch classification, bone-grafting method, clinical outcomes measures, complications, radiolucency around the glenoid component, graft failure, posterior humeral head subluxation, and time of the latest follow-up.

RESULTS

Six studies met the inclusion and exclusion criteria. Ninety-four patients from these 6 studies underwent posterior glenoid bone-grafting with anatomical total shoulder arthroplasty. The mean age was 59.7 years, and the mean duration of follow-up was 5.7 years. Overall, 57% of the patients had an excellent postoperative Neer score. At the time of the latest follow-up, 28.7% had evidence of radiolucency and 35% had humeral head subluxation or instability. Thirteen patients (14%) underwent revision of the glenoid component by the time of the latest follow-up.

CONCLUSIONS

The present study demonstrated a 28.7% complication rate, a 14% revision rate, a 17% graft failure rate, and a 35% rate of recurrence of posterior humeral head subluxation. Posterior glenoid bone-grafting to correct bone loss is associated with a substantial risk of postoperative complications. The treatment of posterior glenoid bone loss remains a challenge in patients undergoing anatomical total shoulder arthroplasty.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Distal clavicle autograft augmentation for glenoid bone loss in revision shoulder arthroplasty: results and technique

BACKGROUND

Structural bone graft for reconstruction of glenoid bone stock is often necessary in the setting of revision shoulder arthroplasty. This study introduces a new structural autograft technique using the distal clavicle for treatment of glenoid bone loss in the setting of revision shoulder arthroplasty.

METHODS

This is a retrospective, single-surgeon study of patients with significant glenoid bone loss requiring revision shoulder arthroplasty with autologous distal clavicle bone grafting to the glenoid. Twenty patients with failed shoulder arthroplasty who underwent revisions of their glenoid components between 2015 and 2019 were retrospectively identified. Sixteen patients were available with follow-up of greater than 1 year. Patient records and radiographs were reviewed for intraoperative and postoperative complications. Preoperative and postoperative function were evaluated by physical examination and patient-reported outcome surveys.

RESULTS

There were no observed intraoperative complications relating to the distal clavicle autograft harvest or placement. There were no iatrogenic nerve injuries or intraoperative instability. One of the 16 patients developed postoperative loosening and subsequent failure of the glenoid baseplate, requiring revision. One additional patient demonstrated increased elevation of the coracoclavicular interval postoperatively, likely related to the distal clavicle autograft harvest. At a mean follow-up of 25 months, 15 of 16 glenoid implants remained well fixed (93.4%), with no evidence of infection, or impingement demonstrated radiographically or clinically. Average patient age was 69 years at the time of surgery. Forward elevation improved from 76° to 123° at final follow-up (P = .0002). The American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form score improved from an average of 35.8 to 67.8 at mean follow-up (P = .001). The visual analog scale score improved from an average of 5.9 to 2 at mean follow-up, though not statistically significant (P = .068). There was no significant change in external rotation following surgery (P = .319).

CONCLUSION

Osteolysis and bone loss of the glenoid poses a challenging problem in revision shoulder arthroplasty. Distal clavicle autograft augmentation is a viable and reproducible technique to manage structural glenoid defects.

Investigating the Effects of Demographics on Shoulder Morphology and Density Using Statistical Shape and Density Modeling

A better understanding of how the shape and density of the shoulder vary among members of a population can help design more effective population-based orthopedic implants. The main objective of this study was to develop statistical shape models (SSMs) and statistical density models (SDMs) of the shoulder to describe the main modes of variability in the shape and density distributions of shoulder bones within a population in terms of principal components (PCs). These PC scores were analyzed, and significant correlations were observed between the shape and density distributions of the shoulder and demographics of the population, such as sex and age. Our results demonstrated that when the overall body sizes of male and female donors were matched, males still had, on average, larger scapulae and thicker humeral cortical bones. Moreover, we concluded that age has a weak but significant inverse effect on the density within the entire shoulder. Weak and moderate, but significant, correlations were also found between many modes of shape and density variations in the shoulder. Our results suggested that donors with bigger humeri have bigger scapulae and higher bone density of humeri corresponds with higher bone density in the scapulae. Finally, asymmetry, to some extent, was noted in the shape and density distributions of the contralateral bones of the shoulder. These results can be used to help guide the designs of population-based prosthesis components and pre-operative surgical planning.

Early results of reverse total shoulder arthroplasty using a patient-matched glenoid implant for severe glenoid bone deficiency

BACKGROUND

Reverse total shoulder arthroplasty (rTSA) in the presence of significant glenoid bone loss remains a challenge. This study presents preliminary clinical and radiographic outcomes of primary and revision rTSA using a patient-matched, 3-dimensionally printed custom metal glenoid implant to address severe glenoid bone deficiency.

METHODS

Between September 2017 and November 2018, 19 patients with severe glenoid bone deficiency underwent primary (n = 9) or revision rTSA (n = 10) using the Comprehensive Vault Reconstruction System (VRS) (Zimmer Biomet, Warsaw, IN, USA) at a single institution. Preoperative and postoperative values for the Disabilities of the Arm, Shoulder and Hand score, Constant score, American Shoulder and Elbow Surgeons score, Simple Shoulder Test score, Single Assessment Numeric Evaluation score, and visual analog scale pain score and active range of motion were compared using the Wilcoxon signed rank test with the level of statistical significance set at P < .05.

RESULTS

Complications occurred in 4 patients (21%), including a nondisplaced greater tuberosity fracture treated conservatively in 1, intraoperative cortical perforation during humeral cement removal treated with an allograft strut in 1, and recurrent instability and hematoma formation treated with humeral component revision in 1. One patient with an early periprosthetic infection was treated with component removal and antibiotic spacer placement at an outside facility and was subsequently lost to follow-up. Eighteen patients with 1-year minimum clinical and radiographic follow-up were evaluated (mean, 18.2 months; range, 12-27 months). Significant improvements were noted in the mean Disabilities of the Arm, Shoulder and Hand score (57.4 ± 16.5 vs. 29.4 ± 19.5, P < .001), mean Constant score (24.6 ± 10.2 vs. 60.4 ± 14.5, P < .001), mean American Shoulder and Elbow Surgeons score (32 ± 18.2 vs. 79 ± 15.6, P < .001), mean Simple Shoulder Test score (4.5 ± 2.6 vs. 9.3 ± 1.8, P < .001), mean Single Assessment Numeric Evaluation score (25.4 ± 13.7 vs. 72.2 ± 17.8, P < .001), mean visual analog scale pain score (6.2 ± 2.9 vs. 0.7 ± 1.3, P < .001), mean active forward flexion (53° ± 27° vs. 124° ± 23°, P < .001), and mean active abduction (42° ± 17° to 77° ± 15°, P < .001). Mean external rotation changed from 17° ± 19° to 32° ± 24° (P = .06). No radiographic evidence of component loosening, scapular notching, or hardware failure was observed at last follow-up in any patient.

CONCLUSION

The preliminary results of rTSA using the VRS to manage severe glenoid bone deficiency are promising, but longer follow-up is necessary to determine the longevity of this implant.

Proximal humeral osteolysis and glenoid radiolucent lines in an anatomic shoulder arthroplasty: a comparison of a ceramic and a metal humeral head component

BACKGROUND

In vitro wear studies demonstrate decreased polyethylene wear with a ceramic compared with a metal humeral head. In this in vivo study, we analyzed prospectively collected 5-year data, comparing the outcomes of 2 types of humeral implants.

METHODS

Sixty-two anatomic total shoulder arthroplasties (TSAs) (59 patients) were performed using the same glenoid component and 2 types of modular humeral implants (metal-head long-stem prosthesis in group A vs. ceramic-head stemless prosthesis in group B). Radiographic analysis for proximal humeral osteolysis and glenoid component radiolucent lines was performed at an average of 5.5 years. Functional outcomes were prospectively evaluated according to the visual analog scale score for pain; satisfaction level; American Shoulder and Elbow Surgeons score; active elevation; Shoulder Pain and Disability Index score; and Disabilities of the Arm, Shoulder and Hand score.

RESULTS

There were 39 TSAs in group A (mean age, 68.1 years) and 23 TSAs in group B (mean age, 67 years). Clinical improvement was similar for both groups. Some proximal humeral osteolysis occurred in 56% of all TSAs. Group A showed increased osteolysis compared with group B (72% vs. 30%, P = .005). Glenoid radiolucent lines were far more frequent in group A, and group A showed a direct relationship between the extent of humeral osteolysis and the severity of glenoid radiolucent lines (P < .001).

CONCLUSION

The stemless ceramic-head replacements showed fewer glenoid radiolucent lines and less humeral osteolysis than the long-stem metal-head replacements. In the group with metal-head replacements, correlation was shown between glenoid radiolucent lines and humeral osteolysis.

Automated quantification of glenoid bone defects using 3-dimensional measurements

BACKGROUND

Assessment of glenoid bone defects is important to select the optimal glenoid component design during shoulder arthroplasty planning and implantation. This study presents a fully automated method to describe glenoid bone loss using 3-dimensional measurements without the need for a healthy contralateral reference scapula.

METHODS

The native shape of the glenoid is reconstructed by fitting a statistical shape model (SSM) of the scapula. The total vault loss percentage, local vault loss percentages, defect depth, defect area percentage, and subluxation distance and region are computed based on a comparison of the reconstructed and eroded glenoids. The method is evaluated by comparing its results with a contralateral bone-based reconstruction approach in a data set of 34 scapula and humerus pairs with unilateral glenoid bone defects.

RESULTS

The SSM-based defect measurements deviated from the contralateral bone-based measurements with mean absolute differences of 5.5% in the total vault loss percentage, 4.5% to 8.0% in the local vault loss percentages, 1.9 mm in the defect depth, 14.8% in the defect area percentage, and 1.6 mm in the subluxation distance. The SSM-based method was statistically equivalent to the contralateral bone-based method for all parameters except the defect area percentage.

CONCLUSION

The presented method is able to automatically analyze glenoid bone defects using 3-dimensional measurements without the need for a healthy contralateral bone.

Revision shoulder arthroplasty: a systematic review and comparison of North American vs. European outcomes and complications

BACKGROUND

Joint registries provide invaluable data on primary arthroplasties with revision as the endpoint; however, the revision outcomes are often excluded. Therefore, a PROSPERO registered review (CRD42015032531) of all revision studies in North America and Europe was conducted to evaluate demographics, etiologies and indications, implant manufacturer, and complications by geographic region.

METHODS

The MEDLINE, EMBASE, and CENTRAL databases were searched for revision arthroplasty clinical studies with a minimum mean 24-month follow-up. There were no language exclusions. Articles published in German, French, and Italian were reviewed by research personnel proficient in each language.

RESULTS

The mean age at revision was 66 ± 5 years (male = 759, female = 1123). The male-female ratio in North American and Europeans studies was 43:57 and 34:66, respectively. The most common etiology for primary surgery in both regions was osteoarthritis or glenoid arthrosis (38%). The most common revision indication overall was rotator cuff tear, deficiency, or arthropathy (26%). The most common implant type used in revisions was a reverse shoulder arthroplasty (54%). The complication rate for all revisions was 17%. There were a total of 465 complications, and of those, 74% lead to a reoperation.

CONCLUSION

Generally, shoulder arthroplasties are designed to last 10-15 years; however, revisions are being performed at a mean 3.9 years from the primary procedure, based on the published studies included in this systematic review. Additionally, of the complications, a large number (74%) went on to a reoperation. Further insight into the reasons for early revisions and standardized reporting metrics and data collection on revisions is needed.