Aims. Recurrent dislocation is both a cause and consequence of glenoid bone loss, and the extent of the bony defect is an indicator guiding operative intervention. Literature suggests that loss greater than 25% requires glenoid reconstruction. Measuring bone loss is controversial; studies use different methods to determine this, with no clear evidence of reproducibility. A systematic review was performed to identify existing CT-based methods of quantifying glenoid bone loss and establish their reliability and reproducibility. Methods. A Preferred Reporting Items for Systematic reviews and Meta-Analyses-compliant systematic review of conventional and grey literature was performed. Results. A total of 25 studies were initially eligible. Following screening, nine papers were included for review. Main themes identified compared 2D and 3D imaging, as well as linear- compared with area-based techniques. Heterogenous data were acquired, and therefore no meta-analysis was performed. Conclusion. No ideal CT-based method is demonstrated in the current literature, however evidence suggests that surface area methods are more reproducible and lead to fewer over-estimations of bone loss, provided the views used are standardized. A prospective imaging trial is required to provide a more definitive answer to this research question. Cite this article: Bone Jt Open 2022;3(2):114–122

Aims. This study aimed to quantify the shoulder kinematics during an apprehension-relocation test in patients with anterior shoulder instability (ASI) and glenoid bone loss using the radiostereometric analysis (RSA) method. Kinematics were compared with the patient’s contralateral healthy shoulder. Methods. A total of 20 patients with ASI and > 10% glenoid bone loss and a healthy contralateral shoulder were included. RSA imaging of the patient’s shoulders was performed during a repeated apprehension-relocation test. Bone volume models were generated from CT scans, marked with anatomical coordinate systems, and aligned with the digitally reconstructed bone projections on the RSA images. The glenohumeral joint (GHJ) kinematics were evaluated in the anteroposterior and superoinferior direction of: the humeral head centre location relative to the glenoid centre; and the humeral head contact point location on the glenoid. Results. During the apprehension test, the centre of the humeral head was 1.0 mm (95% CI 0.0 to 2.0) more inferior on the glenoid for the ASI shoulder compared with the healthy shoulder. Furthermore, the contact point of the ASI shoulder was 1.4 mm (95% CI 0.3 to 2.5) more anterior and 2.0 mm (95% CI 0.8 to 3.1) more inferior on the glenoid compared with the healthy shoulder. The contact point of the ASI shoulder was 1.2 mm (95% CI 0.2 to 2.6) more anterior during the apprehension test compared to the relocation test. Conclusion. The humeral head centre was located more inferior, and the GHJ contact point was located both more anterior and inferior during the apprehension test for the ASI shoulders than the healthy shoulders. Furthermore, the contact point displacement between the apprehension and relocation test revealed increased joint laxity for the ASI shoulder than the healthy shoulders. These results contribute to existing knowledge that ASI shoulders with glenoid bone loss may also suffer from inferior shoulder instability. Cite this article: Bone Joint J 2024;106-B(10):1133–1140

Aims. Glenoid bone loss is a significant problem in the management of shoulder instability. The threshold at which the bone loss is considered “critical” requiring bony reconstruction has steadily dropped and is now approximately 15%. This necessitates accurate measurement in order that the correct operation is performed. CT scanning is the most commonly used modality and there are a number of techniques described to measure the bone loss however few have been validated. The aim of this study was to assess the accuracy of the most commonly used techniques for measuring glenoid bone loss on CT. Methods. Anatomically accurate models with known glenoid diameter and degree of bone loss were used to determine the mathematical and statistical accuracy of six of the most commonly described techniques (relative diameter, linear ipsilateral circle of best fit (COBF), linear contralateral COBF, Pico, Sugaya, and circle line methods). The models were prepared at 13.8%, 17.6%, and 22.9% bone loss. Sequential CT scans were taken and randomized. Blinded reviewers made repeated measurements using the different techniques with a threshold for theoretical bone grafting set at 15%. Results. At 13.8%, only the Pico technique measured under the threshold. At 17.6% and 22.9% bone loss all techniques measured above the threshold. The Pico technique was 97.1% accurate, but had a high false-negative rate and poor sensitivity underestimating the need for grafting. The Sugaya technique had 100% specificity but 25% of the measurements were incorrectly above the threshold. A contralateral COBF underestimates the area by 16% and the diameter by 5 to 7%. Conclusion. No one method stands out as being truly accurate and clinicians need to be aware of the limitations of their chosen technique. They are not interchangeable, and caution must be used when reading the literature as comparisons are not reliable. Cite this article: Bone Jt Open 2023;4(7):478–489

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

Aims. The amount of glenoid bone loss is an important factor in deciding between soft-tissue and bony reconstruction when managing anterior shoulder instability. Accurate and reproducible measurement of glenoid bone loss is therefore vital in evaluation of shoulder instability and recommending specific treatment. The aim of this systematic review is to identify the range methods and measurement techniques employed in clinical studies treating glenoid bone loss. Methods. A systematic review of the PubMed, MEDLINE, and Embase databases was undertaken to cover a ten-year period from February 2011 to February 2021. We identified clinical studies that incorporated bone loss assessment in the methodology as part of the decision-making in the management of patients with anterior shoulder instability. The Preferred Reporting Items for Systematic Reviews (PRISMA) were used. Results. A total of 5,430 articles were identified from the initial search, of which 82 studies met the final inclusion criteria. A variety of imaging methods were used: three studies did not specify which modality was used, and a further 13 used CT or MRI interchangeably. There was considerable heterogeneity among the studies that specified the technique used to quantify glenoid bone loss. A large proportion of the studies did not specify the technique used. Conclusion. This systematic review has identified significant heterogeneity in both the imaging modality and method used to measure glenoid bone loss. The recommendation is that as a minimum for publication, authors should be required to reference the specific measurement technique used. Without this simple standardization, it is impossible to determine whether any published paper should influence clinical practice or should be dismissed. Cite this article: Bone Joint J 2022;104-B(1):12–18

Bone defects are frequently observed in anterior shoulder instability. Over the last decade, knowledge of the association of bone loss with increased failure rates of soft-tissue repair has shifted the surgical management of chronic shoulder instability. On the glenoid side, there is no controversy about the critical glenoid bone loss being 20%. However, poor outcomes have been described even with a subcritical glenoid bone defect as low as 13.5%. On the humeral side, the Hill-Sachs lesion should be evaluated concomitantly with the glenoid defect as the two sides of the same bipolar lesion which interact in the instability process, as described by the glenoid track concept. We advocate adding remplissage to every Bankart repair in patients with a Hill-Sachs lesion, regardless of the glenoid bone loss. When critical or subcritical glenoid bone loss occurs in active patients (> 15%) or bipolar off-track lesions, we should consider anterior glenoid bone reconstructions. The techniques have evolved significantly over the last two decades, moving from open procedures to arthroscopic, and from screw fixation to metal-free fixation. The new arthroscopic techniques of glenoid bone reconstruction procedures allow precise positioning of the graft, identification, and treatment of concomitant injuries with low morbidity and faster recovery. Given the problems associated with bone resorption and metal hardware protrusion, the new metal-free techniques for Latarjet or free bone block procedures seem a good solution to avoid these complications, although no long-term data are yet available. Cite this article: Bone Joint J 2024;106-B(10):1100–1110

Reverse shoulder arthroplasty (RSA) has an increasing effective use in the treatment of patients with a variety of diagnoses, including rotator cuff deficiency, inflammatory arthritis, or failed shoulder prostheses. Glenoid bone loss is not uncommonly encountered in these cases due to the significant wear. Severe bone loss can compromise glenoid baseplate positioning and fixation, consequently increasing the risk for early component loosening, instability, and scapular notching. To manage severe glenoid bone deficiencies, bone grafts are commonly used. Although, many studies report outcome of bone grafting in revision RSA, the literature on humeral head autograft for glenoid bone loss in primary RSA is less robust. The purpose of this study is to evaluate the clinical and radiographic outcomes of primary RSA with humeral head autograft for glenoid bone loss at our institution. Institutional review board approval was obtained to retrospectively review the records of 22 consecutive primary RTSA surgeries in 21 patients with humeral head autograft for glenoid bone loss between January 2008 and December 2016. Five patients died during follow-up, three were unable to be contacted and one refused to participate, leaving a final study cohort of 12 patients with 13 shoulders that underwent RSA. All patients had a clinical evaluation including detailed ROM and clinical evaluation using the American Shoulder and Elbow Surgeons (ASES) Score, Constant Score, Western Ontario Osteoarthritis of the Shoulder Index (WOOS), and Short Form-12 (SF-12) questionnaires. Preoperative and postoperative plain radiographs and CT scans were assessed for component position, loosening, scapular notching, as well as graft incorporation, resorption, or collapse. There were 6 males and 6 females, with an average age of 74 ± 6.8 years. The average BMI was 31.7 ± 5.3, and the median ASA score was 3. Average follow-up was 3.4 ± 1.1 years. The average postoperative range of motion measurements for the operative arm are: flexion = 120 ± 37, abduction = 106 ± 23, external rotation = 14 ± 12, internal rotation at 90 degrees of abduction = 49 ± 7, external rotation at 90 degrees of abduction = 50 ± 28. Average functional scores are: ASES: 76.9 ± 19.2, WOOS: 456 ± 347, SF12 physical: 34.2 ± 8.2, SF12 mental: 54.1 ± 10.2, Constant Score: 64.6 ± 14. No evidence of hardware loosening or evidence of bone graft resorption were encountered. On CT, the average of pre operative B-angle was 79.3 ± 9.3 while the pre operative reverse shoulder angle was 101.4 ± 28. Glenoid retroversion average on CT was 13.3 ± 16.6. Post operative baseplate inclination average was 82 ± 7.4 while the baseplate version 7.8 ±10. The operative technique was able to achieve up to 30 degrees of inclination correction and up to 50 degrees of version correction. In conclusion, primary reverse shoulder arthroplasty with humeral head autograft for glenoid bone loss provides excellent ROM and functional outcomes at mid-term follow-up. This technique has a high rate of bone incorporation and small risk of bone resorption at mid term follow up

Severe glenoid bone loss in patients with osteoarthritis with intact rotator cuff is associated with posterior glenoid bone loss and posterior humeral subluxation. Management of severe glenoid bone loss during shoulder arthroplasty is controversial and technically challenging and options range from humeral hemiarthroplasty, anatomic shoulder replacement with glenoid bone grafting or augmented glenoid component implantation, to reverse replacement with reaming to correct version or structural bone grafting or metallic augmentation of the bone deficiency. Shoulder replacement with severe glenoid bone loss is technically challenging and characterised by higher rates of complications and revisions. Hemiarthroplasty has limited benefit for pain relief and function especially if eccentric glenoid wear exists. Bone loss with >15 degrees of retroversion likely requires version correction include bone-grafting, augmented glenoid components, or reverse total shoulder replacement. Asymmetric reaming may improve version but is limited to 15 degrees of version correction in order to preserve subchondral bone and glenoid bone vault depth. Bone-grafting of glenoid wear and defects has had mixed results with graft-related complications, periprosthetic radiolucent lines, and glenoid component failure of fixation. Implantation of an augmented wedge or step polyethylene glenoid component improves joint version while preserving subchondral bone, but is technically demanding and with minimal short term clinical follow-up. A Mayo study demonstrated roughly 50% of patients with posteriorly augmented polyethylene had radiolucent lines and 1/3 had posterior subluxation. Another wedge polyethylene design had 66% with bone ingrowth around polyethylene fins at 3 years. Long term outcomes are unknown for these new wedge augmented glenoid components. Reverse shoulder arthroplasty avoids many risks of anatomic replacement glenoid component fixation and stability but is associated with a high complication rate (15%) including neurologic and baseplate loosening and often requires structural bone grafting behind the baseplate with suboptimal outcomes or metallic augmented baseplates with limited evidence and short term outcomes. Reverse replacement with baseplate bone grafting or metal augmentation is technically challenging due to limited native glenoid bone stock available for baseplate component ingrowth and long term fixation. Failure to correct glenoid superior inclination and restore neutral version within 10 degrees increases the risks of reverse baseplate failure of fixation, pull out, and failure of reverse replacement. Reverse baseplate failure rates in patients with severe glenoid bone loss and concomitant glenoid bone grafting range from 5–11%. The minimum native glenoid bony contact with the baseplate is unknown but likely is approximately 1cm of native bone contacting a central ingrowth post and a minority (∼15–25%) of native glenoid contacting the backside of the baseplate. Failure to correct posterior bone loss can lead to retroversion of the baseplate, reduced external rotation, posterior scapular notching, and posteromedial polyethylene wear. In summary, shoulder replacement with severe glenoid bone loss is technically challenging and characterised by higher rates of complication and revision

The purpose of this study is to report the clinical and radiological 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. After ethical approval (reference: 17/YH/0318), patients were identified and invited to participate in this observational study. Inclusion criteria included: 1) severe glenoid bone loss necessitating the need for custom implants; 2) patients with definitive glenoid and humeral components implanted more than 2 years prior; 3) ability to comply with patient reported outcome questionnaires. After seeking consent, included patients underwent clinical assessment utilising the Oxford Shoulder Score (OSS), Constant-Murley score, American Shoulder and Elbow Society Score (ASES), and quick Disabilities of the Arm, Shoulder, and Hand Score (quickDASH). Radiographic assessment included AP and axial projections. Patients were invited to attend a CT scan to confirm osseointegration. Statistical analysis utilised included descriptive statistics (mean and standard deviation) and paired t test for parametric data. 3 patients had revision surgery prior to the 2-year follow-up. Of these, 2/3 retained their custom glenoid components. 4 patients declined to participate. 5 patients were deceased at the time of commencement of the study. 21 patients were included in this analysis. The mean follow-up was 36.1 months from surgery (range 22–60.2 months). OSS improved from a mean 16 (SD 9.1) to 36 (SD 11.5) (p < 0.001). Constant-Murley score improved from mean 9 (SD 9.2) to 50 (SD 16.4) (p < 0.001). QuickDASH improved from mean 67 (SD 24) to 26 (SD 27.2) (p = 0.004). ASES improved from mean 28 (SD 24.8) to 70 (SD 23.9) (p = 0.007). Radiographic evaluation demonstrated good osseointegration in all 21 included patients. 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 patient cohort

Aims. Extensive literature exists relating to the management of shoulder instability, with a more recent focus on glenoid and humeral bone loss. However, the optimal timing for surgery following a dislocation remains unclear. There is concern that recurrent dislocations may worsen subsequent surgical outcomes, with some advocating stabilization after the first dislocation. The aim of this study was to determine if the recurrence of instability following arthroscopic stabilization in patients without significant glenoid bone loss was influenced by the number of dislocations prior to surgery. Methods. A systematic review and meta-analysis was performed using the PubMed, EMBASE, Orthosearch, and Cochrane databases with the following search terms: ((shoulder or glenohumeral) and (dislocation or subluxation) and arthroscopic and (Bankart or stabilisation or stabilization) and (redislocation or re-dislocation or recurrence or instability)). Methodology followed the PRISMA guidelines. Data and outcomes were synthesized by two independent reviewers, and papers were assessed for bias and quality. Results. Overall, 35 studies including 7,995 shoulders were eligible for analysis, with a mean follow-up of 32.7 months (12 to 159.5). The rate of post-stabilization instability was 9.8% in first-time dislocators, 9.1% in recurrent dislocators, and 8.5% in a mixed cohort. A descriptive analysis investigated the influence of recurrent instability or age in the risk of instability post-stabilization, with an association seen with increasing age and a reduced risk of recurrence post-stabilization. Conclusion. Using modern arthroscopic techniques, patients sustaining an anterior shoulder dislocation without glenoid bone loss can expect a low risk of recurrence postoperatively, and no significant difference was found between first-time and recurrent dislocators. Furthermore, high-risk cohorts can expect a low, albeit slightly higher, rate of redislocation. With the findings of this study, patients and clinicians can be more informed as to the likely outcomes of arthroscopic stabilization within this patient subset. Cite this article: Bone Joint J 2024;106-B(10):1141–1149

Background. A challenge to obtaining proper glenoid placement in total shoulder arthroplasty is eccentric posterior bone loss and associated glenoid retroversion. This bone loss can lead to poor stability and perforation of the glenoid during arthroplasty. The purpose of this study was to evaluate the three dimensional morphology of the glenoid with associated bone loss for a spectrum of osteoarthritis patients using 3-D computed tomography imaging and simulation software. Methods. This study included 29 patients with advanced glenohumeral osteoarthritis treated with shoulder arthroplasty. Three-dimensional (3D) reconstruction of preoperative CT images was performed using image analysis software. Glenoid bone loss was measured at ten, vertically equidistant axial planes along the glenoid surface at four distinct anterior-posterior points on each plane for a total of 40 measurements per glenoid. The glenoid images were also fitted with a modeled pegged glenoid implant to predict glenoid perforation. Results. The average bone loss was greatest posteriorly in the AP plane at the central axis of the glenoid in the SI plane. Walch A2 and B1 shoulders had bone loss more centrally located, while Walch B2 shoulders displayed more posterior and inferior bone loss. There was a significant difference in the overall average bone loss for patients with no predicted peg perforation compared to patients predicted to have peg perforation (p=0.37). Peg perforation was most common in Walch B2 shoulders, in the posterior direction, and involved the central and posterior-inferior peg. Discussion. These data demonstrate a clear, anatomical pattern of glenoid bone loss for different classes of glenohumeral arthritis. These findings can be used to develop various models of glenoid bone loss to guide surgeons, predict failures, and help develop better glenoid implant

[Hong Kong Orthopaedic Association, Travelling Fellow]. Glenoid bone loss predisposes to further dislocation and failure of arthroscopic Bankart repair in patients with recurrent shoulder dislocation. This study investigates quantification of glenoid bone loss in anterior shoulder dislocation using computerized tomography (CT). CT was performed in 40 patients (average age 31 years, range 16–82 years) with anterior shoulder dislocation. Of this group, 42 shoulders with anterior dislocation and 38 contralateral normal shoulders were examined. In addition, twenty shoulders in ten normal subjects were examined. CT technique comprised 1mm acquisition, pitch 1.0, simultaneously of both shoulders. Reformatted images en face to the glenoid fossa were obtained. Ten different measures of the glenoid fossa were obtained including cross sectional area, maximum height, and width and flattening of the anterior curvature of the glenoid. In normal subjects, maximum side to side difference in cross-sectional area was 14% and maximum glenoid width 4.1mm. For dislocating shoulders, flattening of the anterior edge of the glenoid fossa and a reduction in maximum glenoid width were the best objective criteria of bone loss. Flattening of the anterior glenoid curvature was a feature of 95% dislocated shoulders though was only seen in 1.5% of normal shoulders. Glenoid cross-sectional area was not a useful measure of glenoid bone deficiency. Variable glenoid bone loss is a measurable feature of anterior shoulder dislocation. CT can be used to objectively assess this preoperatively. This should help when deciding on whether to perform an arthroscopic Bankart repair or open bone block procedure

To evaluate humeral and glenoid bone loss in patients surgically treated for shoulder instability as factors of recurrence. During the period 2000–2008, 114 patients (103 men and 11 women) with mean age of 28 yrs underwent arthroscopic treatment for shoulder instability by the same surgeon. Mean age of the 1st shoulder dislocation was 20,89 yo and the average number of dislocations per patient was 17,14. Glenoid bone loss was found in all patients (16 Large, 59 Medium, 29 Small), as well as Hill Sachs lesions (66 Large, 23 Medium, 8 Small) or both. Thirteen (13) patients had an “inverted pear” glenoid shape. Seventy five (75) were into sports and for 57 (76%) of them this involved Overhead/Contact activities. Also 20 patients presented joint hypermobility. Complete follow up existed for 92 patients and it ranged from 4–108 months (Mean=44). The recurrence of instability and the functional outcome were evaluated post-op using the Rowe Zarins Score. Recurrence of instability was noted in 5 patients (4,38%). All of them presented Hill Sachs lesions and glenoid bone loss (2 Large, 2 Medium, 1 Small) but without an “inverted pear” glenoid shape or joint hypermobility. All 5 of them were into Overhead/Contact sports activities (2 Professional: Mean=15hr/w and 3 Amateur: Mean=2,5hr/w). The post op Rowe Zarins Score ranged from 80–100 (Mean=95,11). From the evaluation of our data, it seems that humeral and glenoid bone loss do not significantly contribute to the recurrence of arthroscopically treated shoulder instability

Background: The results of arthroscopic anterior labral (Bankart) repair have been shown to have high failure rate in patients with significant glenoid bone loss. Several reconstruction procedures using bone graft have been described to overcome the bone loss, including autogenous coracoid transfer to the anterior glenoid (Latarjet procedure) as well as iliac crest autograft and tibial allografts. In recent years, trends toward minimally invasive shoulder surgery along with improvements in technology and technique have led surgeons to expand the application of arthroscopic treatment. Purpose: This study aims to perform a retrospective analysis of prospectively collected data to evaluate the clinical and radiological follow up of patient who underwent anatomic glenoid reconstruction using distal tibia allograft for the treatment of shoulder instability with glenoid bone loss at 1-year post operation time point. Between December 2011 and January 2015, 55 patients underwent arthroscopic stabilisation of the shoulder by means of capsule-labral reattachment to glenoid ream and bony augmentation of glenoid bone loss with distal tibial allograft for recurrent instability of the shoulder. Preoperative and postoperative evaluation included general assessment by the western Ontario shoulder instability index (WOSI) questionnaire, preoperative and postoperative radiographs and CT scans. Fifty-five patients have been evaluated with mean age of 29.73 years at time of the index operation. There were 40 males (mean age of 29.66) and 15 female (mean age of 29.93). Minimum follow up time was 12 months. The following adverse effects were recorded: none suffered from recurrent dislocation, 2 patients suffered from bone resorption but without overt instability, 1 patient had malunion due to screw fracture, None of the patients had nonunion. The mean pre-operative WOSI score was 36.54 and the mean postoperative WOSI score was 61.0. Arthroscopic stabilisation of the shoulder with distal tibia allograft augmentation demonstrates promising result at 1year follow up

Glenoid bone loss is not an uncommon challenge in both primary shoulder arthroplasty surgery and revision surgery. Walch described the classification of glenoid morphology and this has led to an understanding of the expanded role for bone grafting, patient-specific implants and reverse prostheses. While bone grafting of the glenoid in conventional arthroplasty has been shown to be successful in some patients it is more routinely used in combination with reverse prostheses. More recently, augmented glenoid components have been developed for both conventional and reverse arthroplasty, though follow-up is insufficient to confirm their durability at this time

There is a large and growing population of patients with shoulder arthritis that are over 70 years old. Many of these patients live alone and sling immobilization after shoulder arthroplasty is problematic. Other than improved internal rotation, there are limited benefits of anatomic shoulder arthroplasty compared to reverse arthroplasty. Anatomic arthroplasty is associated with longer OR time, longer recovery with need for assistance to allow the subscapularis to heal, and more challenging glenoid exposure. The reverse arthroplasty is a faster operation without the need for subscapularis healing and the sphere provides a more forgiving implant position. Additional benefits of reverse arthroplasty include better ability to manage glenoid bone loss and joint subluxation. Data from the Australian Orthopaedic Association National Joint Replacement Registry shows that within the first year of surgery the rate of revision of anatomic shoulder arthroplasty is less than reverse arthroplasty. However, after one year, the overall revision rate of reverse arthroplasty is less than anatomic shoulder arthroplasty. Therefore, increased technical difficulty of anatomic shoulder arthroplasty together with concerns of subscapularis insufficiency, glenoid loosening, and lack of strong evidence of superiority do not warrant changing from reverse for patients over 70 years old

Introduction: The aim of this study was to assess the outcomes of patients with recurrent antero-inferior gle-nohumeral instability with associated antero-inferior glenoid bone loss treated with a specific open stabilisation technique, using intra-substance coracoid bone grafting. It is hypothesised that this method of reconstruction produces low recurrence of instability as well potential for patients to return to high-risk sport. Methods: 30 shoulders with recurrent anterior dislocation and glenoid bone loss were stabilised with open capsular and labral repair and intra-substance coracoid bone grafting. Motion and stability were assessed by Rowe Stability Score (RSS) with follow-up over 2 years in all cases. American Shoulder and Elbow Score (ASES) and Oxford Stability Scoring (OSS) were also recorded at follow-up. Intention to and actual return to sporting level was assessed. Union of the graft was confirmed by CT scan. Results: For all 30 shoulders at a mean follow-up time of 2 years 11 months (range 2–5 years) the RSS improved from a mean of 32 to 78.5 post-op. 1 redislocation occurred whilst continuing high-risk sport after 2 years. ASES index at 2 years had a mean of 91.8 whilst the OSS was 18.5. Pre-operatively, 24 patients participated in high-risk sport. 20 intended to return to high-risk sport post operatively. 18 achieved this return without restriction. CT scans were available on 25 shoulders at a mean of 4.5 months after surgery. 1 showed slight resorption of the graft, union was confirmed in 23. Conclusion: This small sample shows an overall acceptable clinical and radiological outcome at a minimum of 2-year follow-up. These results support the current literature advocating open stabilisation and bone grafting of the glenoid where loss is evident, particularly in the young contact athlete with recurrent instability and high expectations of success

Superiorly eroded glenoids in cuff tear arthropathy represent a surgical challenge for reconstruction. The bone loss orientation and severity may influence glenoid component fixation. This computed-tomography study quantifies both the degree of erosion and orientation in superiorly eroded Favard E2 glenoids. We hypothesized that the erosion in E2 glenoids does not occur purely superiorly, rather, it is oriented in a predictable posterosuperior orientation with a largely semicircular line of erosion.

Three-dimensional reconstructions of 40 shoulders with E2 glenoids (28 female, 12 male patients) at a mean age of 74 years (range, 56–88 years) were created from computed-tomography images. Point coordinates were extracted from each construct to analyze the morphologic structure. The anatomical location of the supra- and infraglenoid tubercle guided the creation of a superoinferior axis, against which the orientation angle of the erosion was measured. The direction and, thus, orientation of erosion was calculated as a vector. By placing ten point coordinates along the line of erosion and creating a circle of best fit, the radius of the circle was placed orthogonally against a chord that resulted by connecting the two outermost points along the line of erosion. To quantify the extent of curvature of the line of erosion between the paleo- and neoglenoid, the length of the radius of the circle of best fit was calculated. Individual values were compared against the mean of circle radii. The area of bony erosion (neoglenoid), was calculated as a percentage of the total glenoid area (neoglenoid + paleoglenoid). The severity of the erosion was categorized as mild (0% to 33%), moderate (34% to 66%), and severe erosion (>66%).

The mean orientation angle between the vector of bony erosion and the superoinferior axis of the glenoid was 47° ± 17° (range, 14° – 74°) located in the posterosuperior quadrant of the glenoid, resulting in the average erosion being directed between the 10 and 11 o'clock position (right shoulder).

In 63% of E2 cases, the line of erosion separating the paleo- and neoglenoids was more curved than the average of all bony erosions in the cohort. The mean surface area of the neoglenoid was 636 ± 247 mm2(range, 233 – 1,333 mm2) and of the paleoglenoid 311 ± 165 mm2(range, 123 – 820 mm2), revealing that, on average, the neoglenoids consume 67% of the total glenoid surface. The extent of erosion of the total cohort was subdivided into one mild (2%), 14 moderate (35%) and 25 severe (62%) cases.

Using a clock-face for orientation, the average orientation of type E2 glenoid defects was directed between the 10 and 11 o'clock position in a right shoulder, corresponding to the posterosuperior glenoid quadrant. Surgeons managing patients with E2 type glenoids should be aware that a superiorly described glenoid erosion is oriented in the posterosuperior quadrant on the glenoid clock-face when viewed intra-operatively. Additionally, the line of erosion in 63% of E2 glenoids is substantially curved, having a significant effect on bone removal techniques when using commercially available augments for defect reconstruction.

Reverse total shoulder arthroplasty (RTSA) has a proven track record as an effective treatment for a variety of rotator cuff deficient conditions. However, glenoid erosion associated with the arthritic component of these conditions can present a challenge for the shoulder arthroplasty surgeon. Options for treatment of glenoid wear include partial reaming with incomplete baseplate seating, bony augmentation using structural or impaction grafting techniques, and augmented baseplates. Augmented components have the advantage of accommodating glenoid deformity with a durable material and also ream less subchondral bone; both of which may offer an advantage over traditional bone grafting.

Biomechanical and early clinical studies of augmented glenoid baseplates suggest they are a reasonable treatment option, though posteriorly augmented baseplates have shown better performance than superiorly augmented implants. However, there are no mid- or late-term studies comparing augmented baseplates to bone grafting or partial reaming.

We present a live surgical demonstration of RTSA for a patient with advanced glenoid erosion being treated with an augmented glenoid baseplate that can be dialed in the direction of any deformity (superior, posterior, etc.). This versatility allows the surgeon to place the augment in any direction and is not confined to the traditional concepts of glenoid wear in a single vector. Clearly, longer term follow up studies are needed to determine the ultimate effectiveness of these devices in treating glenoid deformity in RTSA.