Aims. The scapula is a rare site for a primary bone tumour. Only a small number of series have studied patient outcomes after treatment. Previous studies have shown a high rate of recurrence, with functional outcomes determined by the preservation of the glenohumeral joint and deltoid. The purpose of the current study was to report the outcome of patients who had undergone tumour resection that included the scapula. Methods. We reviewed 61 patients (37 male, 24 female; mean age 42 years (SD 19)) who had undergone resection of the scapula. The most common resection was type 2 (n = 34) according to the Tikhoff-Linberg classification, or type S1A (n = 35) on the Enneking classification. Results. The ten-year disease-specific survival was 76%. High tumour grade (hazard ratio (HR) 4.27; p = 0.016) and a total resection of the scapula (HR 3.84; p = 0.015) were associated with worse survival. The ten-year metastasis-free and local recurrence-free survivals were 82% and 86%, respectively. Total scapular resection (HR 6.29; p = 0.004) was associated with metastatic disease and positive margins were associated with local recurrence (HR 12.86; p = 0.001). At final follow-up, the mean shoulder forward elevation and external rotation were 79° (SD 62°) and 27° (SD 25°), respectively. The most recent functional outcomes evaluated included the mean Musculoskeletal Tumor Society Score (76% (SD 17%)), the American Shoulder and Elbow Score (73% (SD 20%)), and the Simple Shoulder Test (7 (SD 3)). Preservation of the glenoid (p = 0.001) and scapular spine (p < 0.001) improved clinical outcomes; interestingly, preservation of the scapular spine without the glenoid improved outcomes (p < 0.001) compared to preservation of the glenoid alone (p = 0.05). Conclusion. Resection of the scapula is a major undertaking with an oncological outcome related to tumour grade, and a functional outcome associated with the status of the scapular spine and glenoid. Positive resection margins are associated with local recurrence. Cite this article: Bone Joint J 2023;105-B(12):1314–1320

Aims. Scapular notching is thought to have an adverse effect on the outcome of reverse total shoulder arthroplasty (RTSA). However, the matter is still controversial. The aim of this study was to determine the clinical impact of scapular notching on outcomes after RTSA. Methods. Three electronic databases (PubMed, Cochrane Database, and EMBASE) were searched for studies which evaluated the influence of scapular notching on clinical outcome after RTSA. The quality of each study was assessed. Functional outcome scores (the Constant-Murley scores (CMS), and the American Shoulder and Elbow Surgeons (ASES) scores), and postoperative range of movement (forward flexion (FF), abduction, and external rotation (ER)) were extracted and subjected to meta-analysis. Effect sizes were expressed as weighted mean differences (WMD). Results. In all, 11 studies (two level III and nine level IV) were included in the meta-analysis. All analyzed variables indicated that scapular notching has a negative effect on the outcome of RTSA . Statistical significance was found for the CMS (WMD –3.11; 95% confidence interval (CI) –4.98 to –1.23), the ASES score (WMD –6.50; 95% CI –10.80 to –2.19), FF (WMD –6.3°; 95% CI –9.9° to –2.6°), and abduction (WMD –9.4°; 95% CI –17.8° to –1.0°), but not for ER (WMD –0.6°; 95% CI –3.7° to 2.5°). Conclusion. The current literature suggests that patients with scapular notching after RTSA have significantly worse results when evaluated by the CMS, ASES score, and range of movement in flexion and abduction. Cite this article: Bone Joint J 2020;102-B(11):1438–1445

Aims. The aim of this study was to analyse the effect of altered viewing perspectives on the measurement of the glenopolar angle (GPA) and the differences between these measurements made on 3D CT reconstructions and anteroposterior (AP) scapular view radiographs. . Materials and Methods. The influence of the viewing perspective on the GPA was assessed, as were the differences in the measurements of the GPA between 3D CT reconstructions and AP scapular view radiographs in 68 cadaveric scapulae. Results. The median GPA in 3D reconstructions and AP scapular views were 42.7° (95% confidence intervals (CI), 42.0° to 43.5°) and 41.3° (95% CI 40.4° to 42.0°) respectively (p < 0.001). All but five of 20 malpositions demonstrated a significant difference in GPA compared with the respective AP scapular view (p ≤ 0.005). The GPA was most susceptible to malposition in retroversion/anteversion. Inter- and intra-observer reliability for all measurements of the GPA was excellent for 3D CT reconstructions (intraclass correlation (ICC) 0.93 (95% CI 0.87 to 0.96) and 0.94 (95% CI 0.89 to 0.97), respectively) and higher than on AP scapular radiographs (p < 0.001). The intra- and inter-observer reliability was excellent in AP scapular views and malpositions in extension/flexion (ICC ≥ 0.84) but tended to decrease with increasing viewing angle in retroversion/anteversion. Conclusion. These data suggest that 3D reconstructions are more reproducible than AP scapular radiographs in the assessment of the GPA and should be used to compare data in different studies, to predict outcome, define malunion, and act as an indication for surgery in patients with a scapular fracture. Cite this article: Bone Joint J 2016;98-B:1510–16

Aims. Scapular notching is a frequently observed radiographic phenomenon in reverse shoulder arthroplasty (RSA), signifying impingement of components. The purposes of this study were to evaluate the effect of glenoid component size and glenosphere type on impingement-free range of movement (ROM) for extension and internal and external rotation in a virtual RSA model, and to determine the optimal configuration to reduce the incidence of friction-type scapular notching. Materials and Methods. Preoperative CT scans obtained in 21 patients (three male, 18 female) with primary osteoarthritis were analyzed using modelling software. Two concurrent factors were tested for impingement-free ROM and translation of the centre of rotation: glenosphere diameter (36 mm vs 39 mm) and type (centred, 2 mm inferior eccentric offset, 10° inferior tilt). Results. Glenosphere size was most predictive of increased extension and external rotation, whereas lateralization of the centre of rotation was the most predictive factor for internal rotation. A larger diameter of glenosphere combined with a 10° tilted configuration demonstrated superior values for extension and external rotation, whereas the eccentric component improved internal rotation by a mean 8.9° (standard deviation 2.7°) compared with a standard concentric glenosphere. Conclusion. Glenosphere configuration can be modified to increase range of movement in RSA. Friction-type scapular notching was most effectively reduced by use of a large-diameter glenosphere with 10° inferior tilt. Cite this article: Bone Joint J 2018;100-B:1182–6

Between 1998 and 2007, 22 patients with fractures of the scapula had operative treatment more than three weeks after injury. The indications for operation included displaced intra-articular fractures, medialisation of the glenohumeral joint, angular deformity, or displaced double lesions of the superior shoulder suspensory complex. Radiological and functional outcomes were obtained for 16 of 22 patients. Disabilities of the Arm, Shoulder, Hand (DASH) and Short form-36 scores were collected for 14 patients who were operated on after March 2002. The mean delay from injury to surgery was 30 days (21 to 57). The mean follow-up was for 27 months (12 to 72). At the last review the mean DASH score was 14 (0 to 41). Of the 16 patients with follow-up, 13 returned to their previous employment and recreational activities without restrictions. No wound complications, infection or nonunion occurred. Malunion of the scapula can be prevented by surgical treatment of fractures in patients with delayed presentation. Surgery is safe, effective, and gives acceptable functional results

1. Five cases are reported in which snapping of the scapula was caused by subscapular exostosis. In the four cases in which the exostosis was excised, symptoms were relieved without loss of scapular movement. 2. Antero-posterior views of the scapula do not always show the exostosis, and oblique views are recommended. 3. Winging of the scapula may be caused by a subscapular mass, with a neurologically intact subscapularis muscle. 4. Apart from subscapular exostoses, snapping of the scapula may be caused by exostoses or abnormal angles on the ribs, by Luschka's tubercle, or by an abnormal forward curve of the superior angle of the scapula

Aims

The liner design is a key determinant of the constraint of a reverse total shoulder arthroplasty (rTSA). The aim of this study was to compare the degree of constraint of rTSA liners between different implant systems.

The features of congenital elevation of the scapula are described for a group of 16 children. Fibrous bands which tether the scapula and limit its movements were discovered in most children. Vertical displacement osteotomy of the medial border of the scapula and division of the fibrous attachments have provided a reliable and safe treatment for 12 children during the past 10 years

1. One hundred cases of congenital elevation of the scapula are reviewed; thirty-four were treated by operation. 2. A method of grading of appearance is suggested to assist in selecting cases for operation. 3. In very mild cases operation does not confer worthwhile benefit. 4. Very severely affected patients cannot be made to look normal. 5. The appearance often deteriorates during a period of rapid growth of the neck, making continued observation and reassessment essential. 6. The primary aim of treatment is to improve appearance; improvement in function is uncertain. 7. Excision of the supero-medial part of the scapula, and of the omo-vertebral bone when present, is recommended in most cases requiring operation. It is safe and simple, with little risk of loss of function and with simple after-treatment

We report 12 consecutive cases of vertical scapular osteotomy to correct Sprengel’s deformity, performed during a 16-year period, with a mean follow-up of 10.4 years. The mean increase in abduction of the shoulder was 53°. The cosmetic appearance improved by a mean of 1.5 levels on the Cavendish scale. Neither function nor cosmesis deteriorated with time. We recommend the procedure for correction of moderate deformities with a functional deficit

Scapulothoracic fusion (STF) for painful winging of the scapula in neuromuscular disorders can provide effective pain relief and functional improvement, but there is little information comparing outcomes between patients with dystrophic and non-dystrophic conditions. We performed a retrospective review of 42 STFs in 34 patients with dystrophic and non-dystrophic conditions using a multifilament trans-scapular, subcostal cable technique supported by a dorsal one-third semi-tubular plate. There were 16 males and 18 females with a mean age of 30 years (15 to 75) and a mean follow-up of 5.0 years (2.0 to 10.6). The mean Oxford shoulder score improved from 20 (4 to 39) to 31 (4 to 48). Patients with non-dystrophic conditions had lower overall functional scores but achieved greater improvements following STF. The mean active forward elevation increased from 59° (20° to 90°) to 97° (30° to 150°), and abduction from 51° (10° to 90°) to 83° (30° to 130°) with a greater range of movement achieved in the dystrophic group. Revision fusion for nonunion was undertaken in five patients at a mean time of 17 months (7 to 31) and two required revision for fracture. There were three pneumothoraces, two rib fractures, three pleural effusions and six nonunions. The main risk factors for nonunion were smoking, age and previous shoulder girdle surgery. STF is a salvage procedure that can provide good patient satisfaction in 82% of patients with both dystrophic and non-dystrophic pathologies, but there was a relatively high failure rate (26%) when poor outcomes were analysed. Overall function was better in patients with dystrophic conditions which correlated with better range of movement; however, patients with non-dystrophic conditions achieved greater functional improvement

We report the transfer of the sternal part of the pectoralis major to the lower pole of the scapula in 15 patients with winged scapula. At follow-up after 1 to 16 years nine had a satisfactory result and were gainfully employed, though in four of these re-operation had been necessary. Two patients had fair results; the transplant functioned, but they had limited voluntary control. Four were failures: two had had paralysis of other shoulder girdle muscles in addition to the serratus anterior. The indications for the operation are discussed

At The Hospital for Sick Children in Toronto, 21 undescended scapulae were corrected by the Woodward procedure in 20 patients over the past 18 years. The average age at operation was six years six months. The average follow-up period after operation was 8 years 9 months. Fifteen patients were girls and five were boys. All the patients had other associated abnormalities. Only one patient had a concomitant clavicular osteotomy. The average increase in glenohumeral abduction was 37 degrees. The average scapular lowering was two centimetres. Excellent or good cosmetic results were obtained in 80 per cent of patients. Ninety-three per cent of patients expressed satisfaction with the operative results. Complications were few. The Woodward procedure is a safe and relatively straightforward surgical means to effect a good cosmetic and functional improvement in a patient with a congenital undescended scapula. We do not recommend clavicular osteotomy as a routine, but it may be added to gain more correction with less risk of neurovascular compression

1. Resection of the shoulder for a malignant tumour involving the scapula which was too extensive for treatment by excision of the bone is described. 2. The procedure is suggested as an alternative to forequarter amputation in suitable instances

Of forty-six patients with congenital elevation of the scapula, diastematomyelia was confirmed in four and was probably present in five others. Possible reasons for the previously unsuspected association are presented

We have used a modified technique in five patients to correct winging of the scapula caused by injury to the brachial plexus or the long thoracic nerve during transaxillary resection of the first rib. The procedure stabilises the scapulothoracic articulation by using strips of autogenous fascia lata wrapped around the 4th, 6th and 7th ribs at least two, and preferably three, times. The mean age of the patients at the time of operation was 38 years (26 to 47) and the mean follow-up six years and four months (three years and three months to 11 years). Satisfactory stability was achieved in all patients with considerable improvement in shoulder function. There were no complications

The glenopolar angle assesses the rotational alignment of the glenoid and may provide prognostic information and aid the management of scapula fractures. We have analysed the effect of the anteroposterior (AP) shoulder radiograph rotational offset on the glenopolar angle in a laboratory setting and used this to assess the accuracy of shoulder imaging employed in routine clinical practice. Fluoroscopic imaging was performed on 25 non-paired scapulae tagged with 2 mm steel spheres to determine the orientation of true AP views. The glenopolar angle was measured on all the bony specimens rotated at 10° increments. The mean glenopolar angle measured on the bone specimens in rotations between 0° and 20° and thereafter was found to be significantly different (p < 0.001). We also obtained the AP radiographs of the uninjured shoulder of 30 patients treated for fractures at our centre and found that none fitted the criteria of a true AP shoulder radiograph. The mean angular offset from the true AP view was 38° (10° to 65°) for this cohort. Radiological AP shoulder views may not fully project the normal anatomy of the scapular body and the measured glenopolar angle. The absence of a true AP view may compromise the clinical management of a scapular fracture.

Cite this article: Bone Joint J 2013;95-B:1114–20.

This study provides recommendations on the position of the implant in reverse shoulder replacement in order to minimise scapular notching and osteophyte formation. Radiographs from 151 patients who underwent primary reverse shoulder replacement with a single prosthesis were analysed at a mean follow-up of 28.3 months (24 to 44) for notching, osteophytes, the position of the glenoid baseplate, the overhang of the glenosphere, and the prosthesis scapular neck angle (PSNA).

A total of 20 patients (13.2%) had a notch (16 Grade 1 and four Grade 2) and 47 (31.1%) had an osteophyte. In patients without either notching or an osteophyte the baseplate was found to be positioned lower on the glenoid, with greater overhang of the glenosphere and a lower PSNA than those with notching and an osteophyte. Female patients had a higher rate of notching than males (13.3% vs 13.0%) but a lower rate of osteophyte formation (22.9% vs 50.0%), even though the baseplate was positioned significantly lower on the glenoid in females (p = 0.009) and each had a similar mean overhang of the glenosphere.

Based on these findings we make recommendations on the placement of the implant in both male and female patients to avoid notching and osteophyte formation.

Cite this article: Bone Joint J 2013;95-B:530–5.

We hypothesised that a large acromial cover with an upwardly tilted glenoid fossa would be associated with degenerative rotator cuff tears (RCTs), and conversely, that a short acromion with an inferiorly inclined glenoid would be associated with glenohumeral osteoarthritis (OA). This hypothesis was tested using a new radiological parameter, the critical shoulder angle (CSA), which combines the measurements of inclination of the glenoid and the lateral extension of the acromion (the acromion index).

The CSA was measured on standardised radiographs of three groups: 1) a control group of 94 asymptomatic shoulders with normal rotator cuffs and no OA; 2) a group of 102 shoulders with MRI-documented full-thickness RCTs without OA; and 3) a group of 102 shoulders with primary OA and no RCTs noted during total shoulder replacement. The mean CSA was 33.1° (26.8° to 38.6°) in the control group, 38.0° (29.5° to 43.5°) in the RCT group and 28.1° (18.6° to 35.8°) in the OA group. Of patients with a CSA > 35°, 84% were in the RCT group and of those with a CSA < 30°, 93% were in the OA group.

We therefore concluded that primary glenohumeral OA is associated with significantly smaller degenerative RCTs with significantly larger CSAs than asymptomatic shoulders without these pathologies. These findings suggest that individual quantitative anatomy may imply biomechanics that are likely to induce specific types of degenerative joint disorders.

Cite this article: Bone Joint J 2013;95-B:935–41.

In ipsilateral mid-clavicular and scapular-neck fractures, the mechanical stability of the suspensory structures is disrupted and muscle forces and the weight of the arm pull the glenoid fragment distally and anteromedially. To prevent late deformity we recommend internal fixation of the fractured clavicle by a plate and screws. We treated seven patients with this unusual injury; all achieved an excellent functional result without deformity.

We dissected 105 cadaveric shoulders to study the origin of the tendon of the long head of biceps, and examined histologically the interrelationship between the tendon, the supraglenoid tubercle and the superior labrum of the glenoid. In all specimens approximately 50% of the biceps tendon arose directly from the superior glenoid labrum with the remainder attached to the supraglenoid tubercle. The main labral origin was from the posterior labrum in more than half of the specimens, and in a quarter this was the only labral attachment. On the basis of the biceps attachment to the anterior or posterior labrum, we distinguished four types of origin. These normal anatomical variations are significant for arthroscopic diagnosis and may help to explain the various patterns of injury seen in partial or complete detachment of the tendon, the labrum or both.

The April 2024 Oncology Roundup. 360. looks at: Midterm outcomes of total hip arthroplasty after internal hemipelvectomy and iliofemoral arthrodesis; Intraosseous conventional central chondrosarcoma does not metastasize irrespective of grade in pelvis, scapula, and in long bone locations; Oncological and functional outcomes after resection of malignant tumours of the scapula; Reconstruction following oncological iliosacral resection – a comparison of techniques; Does primary tumour resection improve survival for patients with sarcomas of pelvic bones, sacrum, and coccyx who have metastasis at diagnosis?; Older patients with Ewing’s sarcoma: an analysis of the National Cancer Database; Diagnostic challenges in low-grade central osteosarcoma; Effect of radiotherapy on local recurrence, distant metastasis, and overall survival in 1,200 limb soft-tissue sarcoma patients: a retrospective analysis using inverse probability of treatment weighting-adjusted models

Aims. The aim of this study was to compare the clinical and radiological outcomes of reverse shoulder arthroplasty (RSA) using small and standard baseplates in Asian patients, and to investigate the impact of a mismatch in the sizes of the glenoid and the baseplate on the outcomes. Methods. This was retrospective analysis of 50 and 33 RSAs using a standard (33.8 mm, ST group) and a small (29.5 mm, SM group) baseplate of the Equinoxe reverse shoulder system, which were undertaken between January 2017 and March 2021. Radiological evaluations included the size of the glenoid, the β-angle, the inclination of the glenoid component, inferior overhang, scapular notching, the location of the central cage in the baseplate within the vault and the mismatch in size between the glenoid and baseplate. Clinical evaluations included the range of motion (ROM) and functional scores. In subgroup analysis, comparisons were performed between those in whom the vault of the glenoid was perforated (VP group) and those in whom it was not perforated (VNP group). Results. Perforation of the vault of the glenoid (p = 0.018) and size mismatch in height (p < 0.001) and width (p = 0.013) were significantly more frequent in the ST group than in the SM group. There was no significant difference in the clinical scores and ROM in the two groups, two years postoperatively (all p > 0.05). In subgroup analysis, the VP group had significantly less inferior overhang (p = 0.009), more scapular notching (p = 0.018), and more size mismatch in height (p < 0.001) and width (p = 0.025) than the VNP group. Conclusion. In Asian patients with a small glenoid, using a 29.5 mm small baseplate at the time of RSA was more effective in reducing size mismatch between the glenoid and the baseplate, decreasing the incidence of perforation of the glenoid vault, and achieving optimal positioning of the baseplate compared with the use of a 33.8 mm standard baseplate. However, longer follow-up is required to assess the impact of these findings on the clinical outcomes. Cite this article: Bone Joint J 2023;105-B(11):1189–1195

Aims. This study aimed to assess the impact of using the metal-augmented glenoid baseplate (AGB) on improving clinical and radiological outcomes, as well as reducing complications, in patients with superior glenoid wear undergoing reverse shoulder arthroplasty (RSA). Methods. From January 2016 to June 2021, out of 235 patients who underwent primary RSA, 24 received a superior-AGB after off-axis reaming (Group A). Subsequently, we conducted propensity score matching in a 1:3 ratio, considering sex, age, follow-up duration, and glenoid wear (superior-inclination and retroversion), and selected 72 well-balanced matched patients who received a standard glenoid baseplate (STB) after eccentric reaming (Group B). Superior-inclination, retroversion, and lateral humeral offset (LHO) were measured to assess preoperative glenoid wear and postoperative correction, as well as to identify any complications. Clinical outcomes were measured at each outpatient visit before and after surgery. Results. There were no significant differences in demographic data and preoperative characteristics between the two groups. Both groups showed significant improvements in patient-reported outcome measures (visual analogue scale for pain, visual analogue scale for function, American Shoulder and Elbow Surgeons, Constant, and Simple Shoulder Test scores) from preoperative to final assessment (p < 0.001). However, AGB showed no additional benefit. Notably, within range of motion, Group B showed significant postoperative decrease in both external rotation and internal rotation, unlike Group A (p = 0.028 and 0.003, respectively). Both groups demonstrated a significant correction of superior-inclination after surgery, while patients in Group B exhibited a significant decrease in LHO postoperatively (p = 0.001). Regarding complications, Group A experienced more acromial stress fractures (3 cases; 12.5%), whereas Group B had a higher occurrence of scapular notching (24 cases; 33.3%) (p = 0.008). Conclusion. Both eccentric reaming with STB and off-axis reaming with AGB are effective methods for addressing superior glenoid wear in RSA, leading to improved clinical outcomes. However, it is important to be aware of the potential risks associated with eccentric reaming, which include excessive bone loss leading to reduced rotation and scapular notching. Cite this article: Bone Joint J 2024;106-B(3):268–276

Aims. Existing literature indicates that inferiorly inclined glenoid baseplates following reverse total shoulder arthroplasty (RSA) produce better outcomes compared to superiorly inclined baseplates. We aim to compare clinical outcomes for RSAs with superiorly and neutrally/inferiorly inclined lateralized glenospheres. Methods. We retrospectively reviewed 154 consecutive patients undergoing RSA between July 2015 and July 2017 by one single-fellowship trained surgeon (AJ). Two raters (KAM and MVS) independently measured glenoid inclination in preoperative and minimum two year follow-up radiographs (anteroposterior/Grashey) using the RSA angle. Inclination was then compared to patient-reported outcomes, range of motion (ROM), and independently assessed degree of scapular notching and staging of heterotopic ossification at two year follow-up. Results. Median postoperative inclination for each group was found to be -3.6° (interquartile range (IQR) -2.1 to -6.9) and 6.0° (3.2° to 10.1°) for the neutrally/inferiorly and superiorly inclined cohorts, respectively. Preoperative inclination was highly associated with postoperative inclination (p = 0.004). When comparing superiorly and neutrally/inferiorly inclined glenospheres, there were no differences in heterotopic ossification (p = 0.606), scapular notching (p = 0.367), American Shoulder and Elbow Surgeons score (p = 0.419), Single Assessment Numeric Evaluation (p = 0.417), Visual Analogue Scale (VAS) pain score (p = 0.290), forward elevation (p = 0.161), external rotation (p = 0.537), or internal rotation (p = 0.656). Conclusion. Compared to neutral and inferior inclination, up to 6° ± 3° of superior glenoid baseplate inclination on a lateralized RSA design produces no differences in postoperative ROM or patient-reported outcomes, and produces similar levels of scapular notching and heterotopic ossification. Additionally, the degree of preoperative inclination represents an important factor in surgical decision-making as it is strongly associated with postoperative inclination. It is important to note that the findings of this study are only reflective of lateralized RSA prostheses. Cite this article: Bone Joint J 2021;103-B(2):360–365

Aims. Chondrosarcoma is the second most common primary sarcoma of bone: conventional chondrosarcoma accounts for 85% of all cases. Conventional chondrosarcoma may be central or peripheral. Most studies group central and peripheral chondrosarcomas together, although there is growing evidence that their clinical behaviour and prognosis differ. The aims of this study were to analyze any differences in characteristics between central and peripheral chondrosarcomas and to investigate the incidence and role of different syndromes. Methods. Data from two international tertiary referral sarcoma centres between January 1995 and December 2018 were retrospectively reviewed. The study population consisted of 714 patients with surgically treated conventional chondrosarcoma of the pelvis and limbs. Results. In patients with Ollier’s disease and Mafucci’s syndrome, 12/20 (60%) and 2/5 (60%) of malignancies, respectively, were in the limbs, most frequently in the proximal humerus, proximal tibia, and in the hands and feet. In patients with hereditary multiple exostosis (HME), 20/29 (69.0%) of chondrosarcomas were in the pelvis and scapula, specifically in the ilium in 13/29 (44.8%) and the scapula in 3/29 (10.3%). In central chondrosarcoma, survival of patients with Ollier’s disease and non-syndromic patients was the same (p = 0.805). In peripheral chondrosarcoma, survival among HME patients was similar (p = 0.676) in patients with tumours of the pelvis and limbs. Conclusion. Both central and peripheral chondrosarcoma have specific characteristics. HME is frequently seen in patients with a peripheral chondrosarcoma, in whom tumours are commonly located in the ilium and scapula. The incidence of Ollier’s disease is uncommon in patients with a central chondrosarcoma. Disease-specific survival is equal in different subtypes after adjustment for histological grade. The local recurrence-free survival is the same for different locations and subtypes after adjustment for surgical margin. Cite this article: Bone Joint J 2021;103-B(5):984–990

Aims. The objective of this study was to compare simulated range of motion (ROM) for reverse total shoulder arthroplasty (rTSA) with and without adjustment for scapulothoracic orientation in a global reference system. We hypothesized that values for simulated ROM in preoperative planning software with and without adjustment for scapulothoracic orientation would be significantly different. Methods. A statistical shape model of the entire humerus and scapula was fitted into ten shoulder CT scans randomly selected from 162 patients who underwent rTSA. Six shoulder surgeons independently planned a rTSA in each model using prototype development software with the ability to adjust for scapulothoracic orientation, the starting position of the humerus, as well as kinematic planes in a global reference system simulating previously described posture types A, B, and C. ROM with and without posture adjustment was calculated and compared in all movement planes. Results. All movement planes showed significant differences when comparing protocols with and without adjustment for posture. The largest mean difference was seen in external rotation, being 62° (SD 16°) without adjustment compared to 25° (SD 9°) with posture adjustment (p < 0.001), with the highest mean difference being 49° (SD 15°) in type C. Mean extension was 57° (SD 18°) without adjustment versus 24° (SD 11°) with adjustment (p < 0.001) and the highest mean difference of 47° (SD 18°) in type C. Mean abducted internal rotation was 69° (SD 11°) without adjustment versus 31° (SD 6°) with posture adjustment (p < 0.001), showing the highest mean difference of 51° (SD 11°) in type C. Conclusion. The present study demonstrates that accounting for scapulothoracic orientation has a significant impact on simulated ROM for rTSA in all motion planes, specifically rendering vastly lower values for external rotation, extension, and high internal rotation. The substantial differences observed in this study warrant a critical re-evaluation of all previously published studies that examined component choice and placement for optimized ROM in rTSA using conventional preoperative planning software. Cite this article: Bone Joint J 2024;106-B(11):1284–1292

Aims. This systematic review asked which patterns of complications are associated with the three reverse total shoulder arthroplasty (RTSA) prosthetic designs, as classified by Routman et al, in patients undergoing RTSA for the management of cuff tear arthropathy, massive cuff tear, osteoarthritis, and rheumatoid arthritis. The three implant design philosophies investigated were medial glenoid/medial humerus (MGMH), medial glenoid/lateral humerus (MGLH), and lateral glenoid/medial humerus (LGMH). Methods. A systematic review of the literature was performed via a search of MEDLINE and Embase. Two reviewers extracted data on complication occurrence and patient-reported outcome measures (PROMs). Meta-analysis was conducted on the reported proportion of complications, weighted by sample size, and PROMs were pooled using the reported standardized mean difference (SMD). Quality of methodology was assessed using Wylde’s non-summative four-point system. The study was registered with PROSPERO (CRD42020193041). Results. A total of 42 studies met the inclusion and exclusion criteria. Rates of scapular notching were found to be significantly higher in MGMH implants (52% (95% confidence interval (CI) 40 to 63)) compared with MGLH ((18% (95% CI 6 to 34)) and LGMH (12% (95% CI 3 to 26)). Higher rates of glenoid loosening were seen in MGMH implants (6% (95% CI 3 to 10)) than in MGLH implants (0% (95% CI 0 to 2)). However, strength of evidence for this finding was low. No significant differences were identified in any other complication, and there were no significant differences observed in PROMs between implant philosophies. Conclusion. This systematic review has found significant improvement in PROMS and low complication rates across the implant philosophies studied. Scapular notching was the only complication found definitely to have significantly higher prevalence with the MGMH implant design. Cite this article: Bone Joint J 2021;103-B(5):813–821

Aims. Reverse total shoulder arthroplasty (rTSA) can be used in complex cases when the glenoid requires reconstruction. In this study, a baseplate with composite bone autograft and a central trabecular titanium peg was implanted, and its migration was assessed for two years postoperatively using radiostereometric analysis (RSA). Methods. A total of 14 patients who underwent a rTSA with an autograft consented to participate. Of these, 11 had a primary rTSA using humeral head autograft and three had a revision rTSA with autograft harvested from the iliac crest. The mean age of the patients was 66 years (39 to 81). Tantalum beads were implanted in the scapula around the glenoid. RSA imaging (stereographic radiographs) was undertaken immediately postoperatively and at three, six, 12, and 24 months. Analysis was completed using model-based RSA software. Outcomes were collected preoperatively and at two years postoperatively, including the Oxford Shoulder Score, the American Shoulder and Elbow Score, and a visual analogue score for pain. A Constant score was also obtained for the assessment of strength and range of motion. Results. RSA analysis showed a small increase in all translation and rotational values up to six months postoperatively, consistent with settling of the implant. The mean values plateaued by 12 months, with no evidence of further migration. In four patients, there was significant variation outside the mean, which corresponded to postoperative complications. There was a significant improvement in the clinical and patient-reported outcomes from the preoperative values to those at two years postoperatively (p < 0.001). Conclusion. These findings show, using RSA, that a glenoid baseplate composite of a trabecular titanium peg with autograft stabilizes within the glenoid about 12 months after surgery, and reinforce findings from a previous study of this implant/graft with CT scans at two years postoperatively, indicating that this type of structural composite results in sound early fixation. Cite this article: Bone Joint J 2023;105-B(8):912–919

Aims. The aim of this study was to describe a quantitative 3D CT method to measure rotator cuff muscle volume, atrophy, and balance in healthy controls and in three pathological shoulder cohorts. Methods. In all, 102 CT scans were included in the analysis: 46 healthy, 21 cuff tear arthropathy (CTA), 18 irreparable rotator cuff tear (IRCT), and 17 primary osteoarthritis (OA). The four rotator cuff muscles were manually segmented and their volume, including intramuscular fat, was calculated. The normalized volume (NV) of each muscle was calculated by dividing muscle volume to the patient’s scapular bone volume. Muscle volume and percentage of muscle atrophy were compared between muscles and between cohorts. Results. Rotator cuff muscle volume was significantly decreased in patients with OA, CTA, and IRCT compared to healthy patients (p < 0.0001). Atrophy was comparable for all muscles between CTA, IRCT, and OA patients, except for the supraspinatus, which was significantly more atrophied in CTA and IRCT (p = 0.002). In healthy shoulders, the anterior cuff represented 45% of the entire cuff, while the posterior cuff represented 40%. A similar partition between anterior and posterior cuff was also found in both CTA and IRCT patients. However, in OA patients, the relative volume of the anterior (42%) and posterior cuff (45%) were similar. Conclusion. This study shows that rotator cuff muscle volume is significantly decreased in patients with OA, CTA, or IRCT compared to healthy patients, but that only minimal differences can be observed between the different pathological groups. This suggests that the influence of rotator cuff muscle volume and atrophy (including intramuscular fat) as an independent factor of outcome may be overestimated. Cite this article: Bone Jt Open 2021;2(7):552–561

Aims. Reverse total shoulder arthroplasty (RTSA) using trabecular metal (TM)-backed glenoid implants has been introduced with the aim to increase implant survival. Only short-term reports on the outcomes of TM-RTSA have been published to date. We aim to present the seven-year survival of TM-backed glenoid implants along with minimum five-year clinical and radiological outcomes. Methods. All consecutive elective RTSAs performed at a single centre between November 2008 and October 2014 were reviewed. Patients who had primary TM-RTSA for rotator cuff arthropathy and osteoarthritis with deficient cuff were included. A total of 190 shoulders in 168 patients (41 male, 127 female) were identified for inclusion at a mean of 7.27 years (SD 1.4) from surgery. The primary outcome was survival of the implant with all-cause revision and aseptic glenoid loosening as endpoints. Secondary outcomes were clinical, radiological, and patient-related outcomes with a five-year minimum follow-up. Results. The implant was revised in ten shoulders (5.2%) with a median time to revision of 21.2 months (interquartile range (IQR) 9.9 to 41.8). The Kaplan-Meier survivorship estimate at seven years was 95.9% (95% confidence interval (CI) 91.7 to 98; 35 RTSAs at risk) for aseptic mechanical failure of the glenoid and 94.8% (95% CI 77.5 to 96.3; 35 RTSAs at risk) for all-cause revision. Minimum five-year clinical and radiological outcomes were available for 103 and 98 RTSAs respectively with a median follow-up time of six years (IQR 5.2 to 7.0). Median postoperative Oxford Shoulder Score was 38 (IQR 31 to 45); median Constant and Murley score was 60 (IQR 47.5 to 70); median forward flexion 115° (IQR 100° to 125°); median abduction 95° (IQR 80° to 120°); and external rotation 25° (IQR 15° to 40°) Scapular notching was seen in 62 RTSAs (63.2%). Conclusion. We present the largest and longest-term series of TM-backed glenoid implants demonstrating 94.8% all-cause survivorship at seven years. Specifically pertaining to glenoid loosening, survival of the implant increased to 95.9%. In addition, we report satisfactory minimum five-year clinical and radiological outcomes. Cite this article: Bone Joint J 2021;103-B(8):1333–1338

Aims. Open tibial fractures are limb-threatening injuries. While limb loss is rare in children, deep infection and nonunion rates of up to 15% and 8% are reported, respectively. We manage these injuries in a similar manner to those in adults, with a combined orthoplastic approach, often involving the use of vascularised free flaps. We report the orthopaedic and plastic surgical outcomes of a consecutive series of patients over a five-year period, which includes the largest cohort of free flaps for trauma in children to date. Methods. Data were extracted from medical records and databases for patients with an open tibial fracture aged < 16 years who presented between 1 May 2014 and 30 April 2019. Patients who were transferred from elsewhere were excluded, yielding 44 open fractures in 43 patients, with a minimum follow-up of one year. Management was reviewed from the time of injury to discharge. Primary outcome measures were the rate of deep infection, time to union, and the Modified Enneking score. Results. The mean age of the patients was 9.9 years (2.8 to 15.8), and 28 were male (64%). A total of 30 fractures (68%) involved a motor vehicle collision, and 34 (77%) were classified as Gustilo Anderson (GA) grade 3B. There were 17 (50%) GA grade 3B fractures, which were treated with a definitive hexapod fixator, and 33 fractures (75%) were treated with a free flap, of which 30 (91%) were scapular/parascapular or anterolateral thigh (ALT) flaps. All fractures united at a median of 12.3 weeks (interquartile range (IQR) 9.6 to 18.1), with increasing age being significantly associated with a longer time to union (p = 0.005). There were no deep infections, one superficial wound infection, and the use of 20 fixators (20%) was associated with a pin site infection. The median Enneking score was 90% (IQR 87.5% to 95%). Three patients had a bony complication requiring further surgery. There were no flap failures, and eight patients underwent further plastic surgery. Conclusion. The timely and comprehensive orthoplastic care of open tibial fractures in this series of patiemts aged < 16 years resulted in 100% union and 0% deep infection, with excellent patient-reported functional outcomes. Cite this article: Bone Joint J 2021;103-B(6):1160–1167

The outcome of 56 children (61 shoulders) treated surgically at the Rizzoli Institute between April 1975 and June 2010 for congenital elevation of the scapula is reported. There were 31 girls and 25 boys with a mean age at surgery of 6.4 years (2 to 15). The deformity involved the right shoulder in 20 cases, the left in 31 and was bilateral in five. The degree of the deformity was graded clinically and radiologically according to the classifications of Cavendish and Rigault, respectively. All patients underwent a modified Green procedure combined, in selected cases, with resection of the superomedial portion of the scapula and excision of any omovertebral connection. After a mean follow-up of 10.9 years (1 to 29.3), there was cosmetic improvement by at least one Cavendish grade in 54 shoulders (88.5%). The mean abduction of the shoulder improved from 92° (50° to 155°) to 112° (90° to 170°) and the mean flexion improved from 121° (80° to 160°) to 155° (120° to 175°). The unsatisfactory cosmetic result in seven shoulders was due to coexistent scoliosis in two cases and insufficient reduction of the scapular elevation in the other five. An incomplete upper brachial plexus palsy occurred post-operatively in three patients but resolved within seven months. We suggest that a modified Green procedure combined with resection of the superomedial portion of the scapula provides good cosmetic and functional results in patients with Sprengel’s shoulder

Radiological changes and differences between cemented and uncemented components of Grammont reverse shoulder arthroplasties (DePuy) were analysed at a mean follow-up of 9.6 years (8 to 12). Of 122 reverse shoulder arthroplasties implanted in five shoulder centres between 1993 and 2000, a total of 68 (65 patients) were available for study. The indications for reversed shoulder arthroplasty were cuff tear arthropathy in 48 shoulders, revision of shoulder prostheses of various types in 11 and massive cuff tear in nine. The development of scapular notching, bony scapular spur formation, heterotopic ossification, glenoid and humeral radiolucencies, stem subsidence, radiological signs of stress shielding and resorption of the tuberosities were assessed on standardised true anteroposterior and axillary radiographs. A scapular notch was observed in 60 shoulders (88%) and was associated with the superolateral approach (p = 0.009). Glenoid radiolucency was present in 11 (16%), bony scapular spur and/or ossifications in 51 (75%), and subsidence of the stem and humeral radiolucency in more than three zones were present in three (8.8%) and in four (11.8%) of 34 cemented components, respectively, and in one (2.9%) and two (5.9%) of 34 uncemented components, respectively. Radiological signs of stress shielding were significantly more frequent with uncemented components (p < 0.001), as was resorption of the greater (p < 0.001) and lesser tuberosities (p = 0.009)

Objectives. To date, no study has considered the impact of acromial morphology on shoulder range of movement (ROM). The purpose of our study was to evaluate the effects of lateralization of the centre of rotation (COR) and neck-shaft angle (NSA) on shoulder ROM after reverse shoulder arthroplasty (RSA) in patients with different scapular morphologies. Methods. 3D computer models were constructed from CT scans of 12 patients with a critical shoulder angle (CSA) of 25°, 30°, 35°, and 40°. For each model, shoulder ROM was evaluated at a NSA of 135° and 145°, and lateralization of 0 mm, 5 mm, and 10 mm for seven standardized movements: glenohumeral abduction, adduction, forward flexion, extension, internal rotation with the arm at 90° of abduction, as well as external rotation with the arm at 10° and 90° of abduction. Results. CSA did not seem to influence ROM in any of the models, but greater lateralization achieved greater ROM for all movements in all configurations. Internal and external rotation at 90° of abduction were impossible in most configurations, except in models with a CSA of 25°. Conclusion. Postoperative ROM following RSA depends on multiple patient and surgical factors. This study, based on computer simulation, suggests that CSA has no influence on ROM after RSA, while lateralization increases ROM in all configurations. Furthermore, increasing subacromial space is important to grant sufficient rotation at 90° of abduction. In summary, increased lateralization of the COR and increased subacromial space improve ROM in all CSA configurations. Cite this article: A. Lädermann, E. Tay, P. Collin, S. Piotton, C-H Chiu, A. Michelet, C. Charbonnier. Effect of critical shoulder angle, glenoid lateralization, and humeral inclination on range of movement in reverse shoulder arthroplasty. Bone Joint Res 2019;8:378–386. DOI: 10.1302/2046-3758.88.BJR-2018-0293.R1

Inherent disadvantages of reverse shoulder arthroplasty designs based on the Grammont concept have raised a renewed interest in less-medialised designs and techniques. The aim of this study was to evaluate the outcome of reverse shoulder arthroplasty (RSA) with the fully-constrained, less-medialised, Bayley–Walker prosthesis performed for the treatment of rotator-cuff-deficient shoulders with glenohumeral arthritis. A total of 97 arthroplasties in 92 patients (53 women and 44 men, mean age 67 years (standard deviation (. sd. ) 10, (49 to 85)) were retrospectively reviewed at a mean follow-up of 50 months ((. sd. 25) (24 to 96)). The mean Oxford shoulder score and subjective shoulder value improved from 47 (. sd. 9) and 24 points (. sd. 18) respectively before surgery to 28 (. sd. 11) and 61 (. sd. 24) points after surgery (p <  0.001). The mean pain at rest decreased from 5.3 (. sd. 2.8) to 1.5 (. sd. 2.3) (p < 0.001). The mean active forward elevation and external rotation increased from 42. °. (. sd. 30) and 9. °. (. sd. 15) respectively pre-operatively to 78. °. (. sd. 39) and 24. °. (. sd. 17) post-operatively (p < 0.001). A total of 20 patients required further surgery for complications; 13 required revision of components. No patient developed scapular notching. The Bayley–Walker prosthesis provides reliable pain relief and reasonable functional improvement for patients with symptomatic cuff-deficient shoulders. Compared with other designs of RSA, it offers a modest improvement in forward elevation, but restores external rotation to some extent and prevents scapular notching. A longer follow-up is required to assess the survival of the prosthesis and the clinical performance over time. Cite this article: Bone Joint J 2014;96-B:936–42

Reverse total shoulder replacement (RTSR) depends on adequate deltoid function for a successful outcome. However, the anterior deltoid and/or axillary nerve may be damaged due to prior procedures or injury. The purpose of this study was to determine the compensatory muscle forces required for scapular plane elevation following RTSR when the anterior deltoid is deficient. The soft tissues were removed from six cadaver shoulders, except for tendon attachments. After implantation of the RTSR, the shoulders were mounted on a custom-made shoulder simulator to determine the mean force in each muscle required to achieve 30° and 60° of scapular plane elevation. Two conditions were tested: 1) Control with an absent supraspinatus and infraspinatus; and 2) Control with anterior deltoid deficiency. Anterior deltoid deficiency resulted in a mean increase of 195% in subscapularis force at 30° when compared with the control (p = 0.02). At 60°, the subscapularis force increased a mean of 82% (p < 0.001) and the middle deltoid force increased a mean of 26% (p = 0.04). Scapular plane elevation may still be possible following an RTSR in the setting of anterior deltoid deficiency. When the anterior deltoid is deficient, there is a compensatory increase in the force required by the subscapularis and middle deltoid. Attempts to preserve the subscapularis, if present, might maximise post-operative function

Aims. We report the clinical results of glenoid osteotomy in patients with atraumatic posteroinferior instability associated with glenoid dysplasia. Patients and Methods. The study reports results in 211 patients (249 shoulders) with atraumatic posteroinferior instability. The patients comprised 63 men and 148 women with a mean age of 20 years. The posteroinferior glenoid surface was elevated by osteotomy at the scapular neck. A body spica was applied to maintain the arm perpendicular to the glenoid for two weeks postoperatively. Clinical results were evaluated using the Rowe score and Japan Shoulder Society Shoulder Instability Score (JSS-SIS); bone union, osteoarthrosis, and articular congruity were examined on plain radiographs. Results. The Rowe score improved from 36 to 88 points, and the JSS-SIS improved from 47 to 81 points. All shoulders exhibited union without progression of osteoarthritis except one shoulder, which showed osteoarthritic change due to a previous surgery before the glenoid osteotomy. All but three shoulders showed improvement in joint congruency. Eight patients developed disordered scapulohumeral rhythm during arm elevation, and 12 patients required additional open stabilization for anterior instability. Conclusion. Good results can be expected from glenoid osteotomy in patients with atraumatic posteroinferior instability associated with glenoid dysplasia. Cite this article: Bone Joint J 2018;100-B:331–7

Our aim was to determine the most repeatable three-dimensional measurement of glenoid orientation and to compare it between shoulders with intact and torn rotator cuffs. Our null hypothesis was that glenoid orientation in the scapulae of shoulders with a full-thickness tear of the rotator cuff was the same as that in shoulders with an intact rotator cuff. We studied 24 shoulders in cadavers, 12 with an intact rotator cuff and 12 with a full-thickness tear. Two different observers used a three-dimensional digitising system to measure glenoid orientation in the scapular plane (ie glenoid inclination) using six different techniques. Glenoid version was also measured. The overall precision of the measurements revealed an error of less than 0.6°. Intraobserver reliability (correlation coefficients of 0.990 and 0.984 for each observer) and interobserver reliability (correlation coefficient of 0.985) were highest for measurement of glenoid inclination based on the angle obtained from a line connecting the superior and inferior points of the glenoid and that connecting the most superior point of the glenoid and the most superior point on the body of the scapula. There were no differences in glenoid inclination (p = 0.34) or glenoid version (p = 0.12) in scapulae from shoulders with an intact rotator cuff and those with a full-thickness tear. Abnormal glenoid orientation was not present in shoulders with a torn rotator cuff

We evaluated scapular dysplasia and malposition in 15 patients with the Sprengel deformity using three-dimensional CT (3D-CT). The shape, height-to-width ratio, the areas of both scapulae, the anterior curvature of the supraspinous portion and glenoid version were assessed on scapular posterior, medial and inferior views. The degree of rotation and superior displacement were measured on the trunk posterior view. The omovertebral connection was also assessed and correlated with the operative findings. Most of the affected scapulae had a characteristic shape with a decrease in the height-to-width ratio and were larger than the contralateral scapulae. There was an inverse relationship between scapular rotation and superior displacement. The typical curve of the supraspinous portion of the scapula was seen in only three cases. There was no significant difference in glenoid version. The point of tethering of the omovertebral connection may determine the shape, rotation and superior displacement of the scapula. 3D-CT was helpful in delineating the deformity in detail, and in planning scapuloplasty

Aims. The eccentric glenosphere was principally introduced into reverse shoulder arthroplasty to reduce the incidence of scapular notching. There is only limited information about the influence of its design on deltoid power and joint reaction forces. The aim of our study was to investigate how the diameter and eccentricity of the glenosphere affect the biomechanics of the deltoid and the resultant joint reaction forces. . Methods. Different sizes of glenosphere and eccentricity were serially tested in ten cadaveric shoulders using a custom shoulder movement simulator. Results. Increasing the diameter of the glenosphere alone did not alter the deltoid moment arm. However, using an eccentric glenosphere increased the moment arm of the deltoid, lowered the joint reaction force and required less deltoid force to generate movement. Conclusion. Eccentricity is an independent variable which increases deltoid efficiency and lowers joint reaction forces in a reverse shoulder arthroplasty. Cite this article: Bone Joint J 2016;98-B:218–23

Aims

Optimal glenoid positioning in reverse shoulder arthroplasty (RSA) is crucial to provide impingement-free range of motion (ROM). Lateralization and inclination correction are not yet systematically used. Using planning software, we simulated the most used glenoid implant positions. The primary goal was to determine the configuration that delivers the best theoretical impingement-free ROM.

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The aim of this study was to report the long-term prognosis of patients with multiple Langerhans cell histiocytosis (LCH) involving the spine, and to analyze the risk factors for progression-free survival (PFS).

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There remains a lack of consensus regarding the management of chronic anterior sternoclavicular joint (SCJ) instability. This study aimed to assess whether a standardized treatment algorithm (incorporating physiotherapy and surgery and based on the presence of trauma) could successfully guide management and reduce the number needing surgery.

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This study aimed to analyze the accuracy and errors associated with 3D-printed, patient-specific resection guides (3DP-PSRGs) used for bone tumour resection.

Aims. Glenoid bone loss can be a challenging problem when revising a shoulder arthroplasty. Precise pre-operative planning based on plain radiographs or CT scans is essential. We have investigated a new radiological classification system to describe the degree of medialisation of the bony glenoid and that will indicate the amount of bone potentially available for supporting a glenoid component. It depends on the relationship between the most medial part of the articular surface of the glenoid with the base of the coracoid process and the spinoglenoid notch: it classifies the degree of bone loss into three types. It also attempts to predict the type of glenoid reconstruction that may be possible (impaction bone grafting, structural grafting or simple non-augmented arthroplasty) and gives guidance about whether a pre-operative CT scan is indicated. Patients and Methods. Inter-method reliability between plain radiographs and CT scans was assessed retrospectively by three independent observers using data from 39 randomly selected patients. . Inter-observer reliability and test-retest reliability was tested on the same cohort using Cohen's kappa statistics. Correlation of the type of glenoid with the Constant score and its pain component was analysed using the Kruskal-Wallis method on data from 128 patients. Anatomical studies of the scapula were reviewed to explain the findings. Results. Excellent inter-method reliability, inter-observer and test-retest reliability were seen. The system did not correlate with the Constant score, but correlated well with its pain component. . Take home message: Our system of classification is a helpful guide to the degree of glenoid bone loss when embarking on revision shoulder arthroplasty. Cite this article: Bone Joint J 2016;98-B:374–80