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

In patients with shoulder arthritis, the ability to accurately determine glenoid morphological alterations affects the outcomes of shoulder arthroplasty surgery significantly. This study was conducted to determine whether there is a correlation between scapular and glenoid morphometric components. Existence of such a correlation may help surgeons accurately estimate glenoid bone loss during pre-operative planning. The dimensions and geometric relationships of the scapula, scapula apophysis and glenoid were assessed using CT scan images of 37 South African and 40 Chinese cadavers. Various anatomical landmarks were marked on the 77 scapulae and a custom script was developed to perform the measurements. Intra-cohort correlation and inter-cohort differences were statistically analysed using IBM SPSS v28. The condition for statistical significance was p<0.05. The glenoid width and height were found to be significantly (p<0.05) correlated with superior glenoid to acromion tip distance, scapula height, acromion tip to acromion angle distance, acromion width, scapula width, and coracoid width, in both the cohorts. While anterior glenoid to coracoid tip distance was found to be significantly correlated to glenoid height and width in the South African cohort, it was only significantly correlated to glenoid height in the Chinese cohort. Significant (p<0.05) inter-cohort differences were observed for coracoid height, coracoid width, glenoid width, scapula width, superior glenoid to acromion tip distance, and anterior glenoid to coracoid tip distance. This study found correlations between the scapula apophyseal and glenoid measurements in the population groups studied. These morphometric correlations can be used to estimate the quantity of bone loss in shoulder arthroplasty patients

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

During shoulder arthroplasty the native functionality of the diseased shoulder joint is restored, this functionality is strongly dependent upon the native anatomy of the pre-diseased shoulder joint. Therefore, surgeons often use the healthy contralateral scapula to plan the surgery, however in bilateral diseases such as osteoarthritis this is not always feasible. Virtual reconstructions are then used to reconstruct the pre-diseased anatomy and plan surgery or subject-specific implants. In this project, we develop and validate a statistical shape modeling method to reconstruct the pre-diseased anatomy of eroded scapulae with the aim to investigate the existence of predisposing anatomy for certain shoulder conditions. The training dataset for the statistical shape model consisted of 110 CT images from patients without observable scapulae pathologies as judged by an experienced shoulder surgeon. 3D scapulae models were constructed from the segmented images. An open-source non-rigid B-spline-based registration algorithm was used to obtain point-to-point correspondences between the models. The statistical shape model was then constructed from the dataset using principle component analysis. The cross-validation was performed similarly to the procedure described by Plessers et al. Virtual defects were created on each of the training set models, which closely resemble the morphology of glenoid defects according to the Wallace classification method. The statistical shape model was reconstructed using the leave-one-out method, so the corresponding training set model is no longer incorporated in the shape model. Scapula reconstruction was performed using a Monte Carlo Markov chain algorithm, random walk proposals included both shape and pose parameters, the closest fitting proposal was selected for the virtual reconstruction. Automatic 3D measurements were performed on both the training and reconstructed 3D models, including glenoid version, critical shoulder angle, glenoid offset and glenoid center position. The root-mean-square error between the measurements of the training data and reconstructed models was calculated for the different severities of glenoid defects. For the least severe defect, the mean error on the inclination, version and critical shoulder angle (°) was 2.22 (± 1.60 SD), 2.59 (± 1.86 SD) and 1.92 (± 1.44 SD) respectively. The reconstructed models predicted the native glenoid offset and centre position (mm) an accuracy of 0.87 (± 0.96 SD) and 0.88 (± 0.57 SD) respectively. The overall reconstruction error was 0.71 mm for the reconstructed part. For larger defects each error measurement increased significantly. A virtual reconstruction methodology was developed which can predict glenoid parameters with high accuracy. This tool will be used in the planning of shoulder surgeries and investigation of predisposing scapular morphologies

Introduction. The clinical impact of scapular notching is controversial. Some reports suggest it has no impact while others have demonstrated it does negatively impact clinical outcomes. The goal of this clinical study is to analyze the pre- and post-operative outcomes of 415 patients who received rTSA with one specific prosthesis (Equinoxe; Exactech, Inc). Methods. 415 patients (mean age: 72.2yrs) with 2 years minimum follow-up were treated with rTSA for CTA, RCT, and OA by 8 fellowship trained orthopaedic surgeons. 363 patients were deemed to not have a scapular notch by the implanting surgeon at latest follow-up (72.1 yrs; 221F/131M) whereas 52 patients were deemed to have a scapular notch at latest follow-up (73.3 yrs; 33F/19M). Outcomes were scored using SST, UCLA, ASES, Constant, and SPADI metrics; active abduction, forward flexion, and internal/external rotation were also measured to quantify function. Average follow-up was 38.1 months (No Notch: 37.2; Notch: 44.4). A two-tailed, unpaired t-test identified differences (p<0.05) in pre-operative, post-operative, and pre-to-post improvements. Results. The overall scapular notching rate was 12.5%. The rTSA cohort with a scapular notch had an average notching grade of 1.3 (41 grade 1, 6 grade 2, 5 grade 3, and 0 grade 4 notches). rTSA patients with a scapular notch on average weighed significantly less (168.0 vs. 154.7 lbs; p = 0.016) and had a significantly lower BMI (27.3 vs. 26.0; p = 0.032). 8 patients without scapular notching had a radiolucent line around the humeral component (2.2%); whereas, 5 patients with scapular notching had a radiolucent line around the humeral component (10.0%). Table 1 demonstrates no difference between the cohorts in pre-operative outcomes. Table 2 demonstrates rTSA patients without scapular notching were associated with significantly larger clinical outcome scores in all 5 metrics and also had significantly improved function according to 3 of the 6 measurements as compared to rTSA patients with scapular notching. Table 3 demonstrates only one significant difference was observed in pre-to-post improvement of outcome scores between cohorts. Finally, 27 complications were reported (6.5%), 20 for patients without scapular notching (5.5%) and 7 complications for patients with scapular notching (13.5%). Discussion and Conclusions. This large-scale clinical outcome study demonstrated that patients with scapular notching are associated with significantly poorer outcomes and a greater complication rate than patients without scapular notching at a similar average post-operative follow-up. The finding that patients with lower BMI were associated with a higher notching rate is new but also intuitive as these patients can likely adduct their arm more; it may also be that the lower average BMI and weight suggests that patients with notching were also more active. One additional new finding in this analysis is that patients with scapular notching had a 4.5X greater rate of radiolucent lines around the humeral component suggesting that the UHWMPE wear debris are related to the formation of humeral radiolucent lines. Additional and longer-term follow-up is needed to confirm these conclusions

Introduction. Snapping scapula symptoms occur due to disruption of the smooth gliding motion between scapula and thoracic cage. Patients present with pain in the scapulothoracic area aggravated by overhead and repetitive shoulder movements. It is often associated with audible and palpable crepitus, clicking, crunching, grating or snapping sensation. Open or arthroscopic scapulothoracic surgical treatment is an option when non-operative treatment modalities fail. The aim of our study was to assess the outcome of scapulothoracic arthroscopic treatment in patients with painful snapping scapula. Methods. Eight patients underwent scapulothoracic arthroscopic treatment for painful snapping scapula. Pre-operatively, all these patients had a trial of conservative treatment modalities for at least 6 months, consisting of activity modification, analgesia and physiotherapy for restoration of normal scapulothoracic kinematics. All patients had a temporary pain relief following a local anaesthetic and steroid injection. We graded the crepitus from 0 to 3 - 0 being no crepitus, 1 being palpable but not audible crepitus, 2 being soft audible crepitus and 3 being loud crepitus. Operations were performed with the patients in either prone or semi-prone position. The arm was placed in the “chicken wing” position (arm in full internal rotation with the hand placed on the back), so that the scapula lifted up from the chest wall. Two portals along the medial border of scapula were used for arthroscopy and instrumentation. In two cases a superior portal was also used. Outcome was assessed by pre and postoperative visual analogue score (VAS) and Oxford Shoulder Score. Pre and postoperative scores were compared using paired t-test. The significance level was set at P <. 05. Results. Of the eight patients included in our study, two were male and six were female patients. Mean age at the time of surgery was 26 years (range 16–34 years). Based on the preoperative clinical and MRI/CT findings and intra-operative arthroscopic findings, five had scapulothoracic bursectomy and 3 had bursectomy and shaving of superomedial border of scapula. Mean follow up was 5 months (Range 2 to 7 months). VAS score improved significantly from a mean of 9.4 preoperatively to 2.4 (P value .0002). There was also a significant improvement in Oxford Shoulder Score from a mean of 8.7 pre-operatively to 34.7 post operatively (P= .0001). Mean crepitus score significantly decreased from 2.6 to 0.3 (p <.0001). In six patients crepitus completely resolved. In two there was residual palpable crepitus but they had good pain relief. All eight patients were happy with the outcome of their surgery and will recommend this procedure to patients with similar symptoms. Conclusion. Arthroscopic scapulothoracic treatment provides significant pain relief and functional improvement for painful snapping scapula symptoms not responding to non surgical treatment modalities

Background. Glenoid baseplate fixation for reverse shoulder arthroplasty relies on the presence of sufficient bone stock and quality. Glenoid bone may be deficient in cases of primary erosions or due to bone loss in the setting of revision arthroplasty. In such cases, the best available bone for primary baseplate fixation usually lies within the three columns of the scapula. The purpose of this study was to characterise the relationship of the three columns of the scapula independent of glenoid anatomy and to establish the differences between male and female scapular anatomy. Methods. Fifty cadaveric scapulae (25 male, 25 female) were analysed using CT-based imaging software. The surface geometries of the coracoid, scapular spine and inferior scapular column were delineated in the sagittal plane. A linear best-fit line was drawn to establish the long axis of each column independent of the glenoid. The width of the glenoid was measured and points marked at the midpoint of each measurement. A best-fit line starting at the supra glenoid tubercle passing through the midpoints was chosen as the superior inferior (SI) axis of the glenoid. An orthogonal plane to the scapular plane was developed parallel to the glenoid face. The axis representing each of the three columns of the scapula and the SI axis of the glenoid, were projected onto this plane. The relationship between each column was analysed with respect to each other and with respect to the SI glenoid axis. Thus, measurements obtained gave the relationships of the three columns of the scapula (independent of the glenoid) and their relationships to the long axis of the glenoid (dependant on the glenoid). Comparisons were made between males and females using the independent t-tests. Results. The mean angle between the scapular spine and the coracoid column was 93±13° with no significant difference between males (91±15°) and females (95±10°) (p=0.29). The angle between the inferior scapular column and the scapular spine was 6.5° greater (p=0.03) in females (134±10°) than in males (128±11°). Similarly, the angle between the inferior scapular column and the coracoid column was 11° greater (p=0.009) in males (141±15°) than in females (130±12°). No significant sex difference was found between the acromion and inferior scapular pillar with respect to the SI glenoid axis. However, the female coracoid was found to be more horizontal than the male coracoid in relation to the SI axis of the glenoid (p=0.037). Conclusion. This study demonstrates that the relationship between the scapular spine and the coracoid column is independent of sex. However, sex has significant effects on the positions of the scapular spine and coracoid columns with respect to the inferior scapular column. The inferior scapular column is noted to be positioned more anterior (closer to the coracoid) in females than in males. Sex variations may be important when directing screws for baseplate fixation in bone deficient glenoids undergoing reverse shoulder arthroplasty

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

Summary Statement. Sprengel's deformity is a rare congenital anomaly, with scapula malposition. We present a unique subgroup of Sprengel's possessing a cleithrum, an ancestral remnant of shoulder-girdle development found in bony-fish. This challenges management providing valuable insight into scapular embryology and development. Introduction. Sprengel's deformity is a rare congenital anomaly of the shoulder girdle characterised by scapula malposition, associated with atrophy of periscapular muscles causing disfigurement and limited shoulder movement. Traditionally, it has been managed by omovertebral bar excision and muscle transplantation procedures guided by age and Cavendish grading. We present a unique, previously undescribed observation in humans: a case series of patients with Sprengel's deformity possessing a cleithrum, an ancestral remnant of shoulder-girdle development found in archaic bony fish. Methods. Nine patients presented with a so-called ‘Sprengel deformity’ to a tertiary referral shoulder clinic. All were assessed clinically and radiologically with scapular radiographs, and CT and/or MRI scans. The clinical (functional and cosmetic) and radiological features were classified according to Cavendish and Rigault systems, respectively and scapular ratio, assessed. Results. All patients were classed grade 4 on the Cavendish scale. Six were grade 2 and three were grade 3 on the Rigault scale. Mean scapular ratio was 1.04. Associated renal, craniocervical and cervicothoracic anomalies were present. The distinguishing surgical patho-anatomical feature was partial endomuscular ossification of medial scapular suspension muscles, analogous with the cleithrum of bony fish. The bone commonly articulated with the spinal column through pseudarthroses. Conclusions. This finding of the cleithrum not only challenges classic management of this rare patient group, as it cannot be managed by traditional muscle transplantation procedures, but offers insight into scapular embryology and development. The association of scapular developmental and urogenital anomalies suggests screening investigation of renal tracts in those with undescended scapula syndrome is relevant, and further genetic investigation might be pertinent to understand scapular development and pathology. We suggest, to emphasise the nature of the incomplete scapular descent and associated congenital anomalies, and clarify the imprecise common usage of the term ‘Sprengel’ this condition be called the ‘Congenital Undescended Scapula Syndrome’

The purpose of this study is to quantify the distribution of bone density in the scapulae of patients undergoing reverse shoulder arthroplasty (RSA) to guide optimal screw placement. To achieve this aim, we compared bone density in regions around the glenoid that are targeted for screw placement, as well as bone density variations medial to lateral within the glenoid. Specimen included twelve scapula in 12 patients with a mean age of 74 years (standard deviation = 9.2 years). Each scapula underwent a computed tomography (CT) scan with a Lightspeed+ XCR 16-Slice CT scanner (General Electric, Milwaukee, USA). Three-dimensional (three-D) surface mesh models and masks of the scapulae containing three-D voxel locations along with the relative Hounsfield Units (HU) were created. Regions of interest (ROI) were selected based on their potential glenoid baseplate screw positioning in RSA surgery. These included the base of coracoid inferior and lateral to the suprascapular notch, an anterior and posterior portion of the scapular spine, and an anterosuperior and inferior portion of the lateral border. Five additional regions resembling a clock face, on the glenoid articular surface were then selected to analyze medial to lateral variations in bone density including twelve, three, six, and nine-o'clock positions as well as a central region. Analysis of Variance (ANOVA) tests were used to examine statistical differences in bone density between each region of interest (p < 0 .05). For the regional evaluation, the coracoid lateral to the suprascapular notch was significantly less dense than the inferior portion of the lateral border (mean difference = 85.6 HU, p=0.03), anterosuperior portion of the lateral border (mean difference = 82.7 HU, p=0.04), posterior spine (mean difference = 97.6 HU, p=0.007), and anterior spine (mean difference = 99.3 HU, p=0.006). For the medial to lateral evaluation, preliminary findings indicate a “U” pattern with the densest regions of bone in the glenoid most medially and most laterally with a region of less dense bone in-between. The results from this study utilizing clinical patient CT scans, showed similar results to those found in our previous cadaveric study where the coracoid region was significantly less dense than regions around the lateral scapular border and scapular spine. We also have found for medial to lateral bone density, a “U” distribution with the densest regions of bone most medially and most laterally in the glenoid, with a region of less dense bone between most medial and most lateral. Clinical applications for our results include a carefully planned trajectory when placing screws in the scapula, potentially avoiding the base of coracoid. Additionally, surgeons may choose variable screw lengths depending on the region of bone and its variation of density medial to lateral, and that screws that pass beyond the most lateral (subchondral) bone, will only achieve further purchase if they enter the denser bone more medially. We suspect that if surgeons strategically aim screw placement for the regions of higher bone density, they may be able to decrease micromotion in baseplate fixation and increase the longevity of RSA

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

Twenty-three patients with scapular chondrosarcomas presented to our institution between 1989 and 2003. Twenty-two were treated surgically while one presented with metastases and was treated palliatively. Fourteen patients underwent partial scapulectomy and eight had a Tikhoff-Linberg procedure. There were no local recurrences and only two patients have suffered a systemic recurrence at mean follow-up of fifty-two months. Mean functional scores were: TESS – 88, MSTS 1987 – 27 and MSTS 1993 – 84. Overall, the oncologic and functional outcome for these patients was excellent. To examine the oncologic and functional outcome of patients treated for chondrosarcoma of the scapula. Rates of local recurrence and metastasis for adequately treated chondrosarcomas of the scapula were very low and patient function was quite good. Unlike previous reports in the literature, we found that scapular chondrosarcomas are highly amenable to limb salvage surgery and the oncologic and functional outcomes are excellent. Retrospective review of our prospectively collected database for all patients treated surgically at our institution for scapular chondrosarcoma between 1989 and 2003. Twenty-three patients presented with scapular chondrosarcoma, but one had spine metastases and was treated palliatively. Thus twenty-two patients were treated with limb salvage surgery. There were fourteen males and eight females. One patient presented as a local recurrence. Four tumors were grade one, sixteen grade two and two grade three. Eight were secondary to a primary benign primary tumor of bone. There were fourteen partial scapulectomies and eight Tikhoff-Linberg procedures. Surgical margins were positive in three cases. two patients received post-operative radiation and no patients received adjuvant chemotherapy. At last follow-up, twenty patients were alive with no evidence of disease (90.9%), one was alive with disease and one was dead of disease. There were two systemic recurrences and no local recurrences at an average follow-up of fifty-two months (range 12–113). Mean functional scores were: TESS – 88, MSTS – 1987 27 and MSTS 1993 – 84

Summary Statement. We measured scapulothoracic motions during humeral abduction with different humeral rotations in healthy subjects and whole cadaver models and clarified that humeral rotation significantly influenced scapular kinematics. Introduction. Scapular dyskinesis has been observed in various shoulder disorders such as impingement syndrome or rotator cuff tears. However, the relationship between scapular kinematics and humeral positions remains unclear. We hypothesised that humeral rotation would influence scapular motions during humeral abduction and measured scapular motion relative to the thorax in the healthy subjects and whole cadavers. Methods. Healthy Subjects: Twenty-four shoulders of twelve healthy subjects without shoulder disorders were enrolled. Three electromagnetic sensors were attached on the skin over the sternum, scapula and humerus. Scapular motions during scapular plane abduction (abduction) were measured. The measurements were performed with four hand positions, palm up, thumb up, palm down and thumb down. The elbow was kept extended in all measurements. Each measurement took 5 seconds and repeated three times. Cadavers: Twelve shoulders from 6 fresh whole cadavers were used. A cadaver was set in sitting position on a wooden chair without interrupting scapular motions. Electromagnetic sensors were attached on the thorax, scapula and humerus rigidly with transcortical pins. The elbow was kept in extended position by holding the forearm and the arm was moved passively. The measurements were performed during scapular plane abduction and scapular kinematics were measured in four hand positions, 1: thumb up, 2; palm up, 3; palm down, 4; thumb down as well as the healthy subjects. Each measurement took 5 seconds and repeated three times. Data Analysis: The coordinate system and rotation angles of the thorax, scapula and humerus were decided following ISB recommendation. A one-way analysis of variance was used to test the differences in 4 arm positions. Dunnet's multiple post hoc tests were used to identify the difference between thumb up model (neutral rotation) and other three arm positions. Results. Scapular posterior tilt increased during palm up abduction (healthy subjects −2.0° to 0.1°, cadaver −3.2° to −1.4° at 120° of abduction). During thumb-down abduction, scapular posterior tilt decreased (healthy subjects −4.1° to −8.0° at 110° of abduction, cadaver −3.2° to −8.6° at 120° of abduction) and scapular upward rotation increased (healthy subjects 21.0° to 26.1° at 110° of abduction, cadaver 25.3° to 31.1° at 120° of abduction). Thumb down abduction demonstrated no significant difference from thumb up position. Discussion. Scapular motions measured in healthy subjects and cadaver models showed similar patterns indicating that surface markers on the healthy subjects could track scapular motions successfully as bone markers in cadaver models. Humeral external rotation increased scapular posterior tilt and humeral internal rotation increased scapular anterior tilt and upward rotation. This suggests that position of the greater and lesser tuberosity and tension of the joint capsule caused scapular tilt and scapular upward rotation. Kinematic changes caused by humeral rotations were observed in earlier phase of abduction in healthy subjects than in cadaver models. This suggests that healthy subjects set scapular position beforehand not to increase subacromial pressure. Conclusion. Humeral rotation significantly influenced scapular kinematics. Assessment for these patterns is important for evaluation of shoulder pathology associated with abnormal scapular kinematics

Background. There has been increased focus on understanding the risk factors associated with scapular notching in reverse shoulder arthroplasty (RSA). The purpose of this study is to evaluate the effect of scapular morphology and surgical technique on the occurrence of scapular notching using the notching index as a comprehensive predictive tool. Methods. Ninety-one patients treated with a primary RSA were followed for a minimum of 24 months. Using a previously published notching index formula ((PSNA × 0.13) + (PGRD)), a notching index value for all patients was calculated. Radiographic assessment of patients were grouped by Nerot grade of scapular notching, group mean differences for prosthetic scapular neck angle (PSNA), peg glenoid rim distance (PGRD), preoperative scapular neck angle (SNA), notching index and clinical outcomes were compared. Results. Seventy-five (82%) of the ninety one shoulders in the study developed scapular notching. There was no significant difference in average notching index for group 1, 31.8 ± 4.4, and group 2, 33.1 ± 7.2. No significant difference was demonstrated between the groups for SNA (102.7° vs. 105.4°, p = 0.3), PSNA (125.8° vs. 124.5°, p = 0.82), PGRD (15.4 mm vs. 16.8 mm, p = 0.47) or in clinical outcomes between groups. Discussion. Our results demonstrated an overall low notch index that lacked specificity in predicting notching for this cohort. These results suggest that perhaps PSNA and prosthetic design are more significant contributors to notching with certain scapular morphology

Aim: To quantify the effect of overhead sports on static scapular position. Method: Three cohorts of young adults were evaluated: Swimmers (n=35), Tennis players (n=32) and Controls (n=33). Scapular position was determined using the method described by DiVita. Details of overhead activities, hand dominance and history of shoulder injuries were obtained by questionnaire. All measurements were performed by a single observer. Results: DiVita’s normalised ratios in dominant shoulders were 1.57±0.09 for swimmers, 1.61±0.11 for tennis players and 1.57±0.12 for controls. For non-dominant shoulders, the ratios were 1.58±0.1.5, 1.59±0.13 and 1.63±0.13 respectively. There were no significant differences between groups. Within male subjects, there were no differences in scapular size between athletes and controls on either dominant or non-dominant sides. However, scapular distance was significantly greater in swimmers in both shoulders (dominant p=0.009, non-dominant p=0.028) and in the dominant shoulder in tennis players (p=0.037) when compared with controls. Female athletes showed no differences in scapular size when compared with controls but female swimmers had greater scapular sizes on their non-dominant sides when compared with controls (p=0.016). Conclusions: There were measurable anthropometric differences between athletes and controls that supported our hypothesis of greater scapular distances in both shoulders in swimmers and in the dominant shoulder in tennis players when compared with controls. However, these were not borne out using a normalised ratio. DiVita’s method of assessing static scapula position is readily applicable to clinical and sporting settings and proved reproducible with minimal equipment. It may be worthy of further investigation

Introduction: Classical studies have defined axes from prominent scapular landmarks that have been used to synthesise many applications. The morphology of the scapula is however known to be highly variable between individuals. 1. ,. 2. ,. 3. This introduces significant variability on the use of these classical axes for various clinical applications. Also, some of the literatureapplied landmarks were highly dependant on the presence of pathology, thus introducing more variability in the products they parented. This limits accuracy in inter-subject comparisons from such applications. Therefore there is a need to identify and define pathology-insensitive anatomical landmarks that are less variable between individuals than the variability of the overall scapular shape. The aim of this study was to define more scapular axes from clearly identifiable landmarks, analysing these and other classical definitions for the best axis that minimizes variability and is closely related to the scapular clinical frame of reference. Materials and Method: Fourteen different axes of new and classical definitions from clearly identifiable landmarks were quantified by applying medical images of 21 scapulae. The orientations of the quantified axes were calculated. The plane of the blade of the scapula was defined, bounded by the angulus inferior. 4. , the spine/medial border intersection. 5. and the most inferolateral point of the infra-glenoid tubercle. This was applied to grade the alienation of the quantified axes from the scapular blade. The angular relationships between individual axes of a spcapula were quantified, averaged over the 21 specimens and their standard deviations (SD) applied to grade the sensitivity of each axis to interscapular variations in the others. The volume of data required to define an axis (VDA) was noted for its dependency on pathology. These three criteria were weighted according to relative importance such that. axes bearing 10° or more from the blade deviated significantly and were eliminated;. insensitivity to scapular morphological variations based on the smallest SD and axes applicability in pathology based on VDA of the remaining axes were graded for the final result. Results: A least square line through the centre of the spine root was the most optimal medio-lateral axis. The normal to the plane formed by the spine root line and a least square line through the centre of the lateral border ridge was the most optimal antero-posterior axis. Conclusion: These body-fixed axes are closely aligned to the cardinal planes. 6. in the anatomical position and thus are clinically applicable, specimen invariant axes that can be used in generalised and patient-specific kinematics modelling

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.

Scapular notching is of concern in reverse shoulder arthroplasty and has been suggested as a cause of glenoid loosening. Our purpose was to analyze in a large series the characteristics and the consequences of the notch and then to enlighten the causes in order to seek some solutions to avoid it. 430 consecutive patients (457 shoulders) were treated by a reverse prosthesis for various etiologies between 1991 and 2003 and analyzed for this retrospective multicenter study. Adequate evaluation of the notch was available in 337 shoulders with a follow-up of 47 months (range, 24–120 months). The notch has been diagnosed in 62% cases at the last follow-up. Intermediate reviews show that the notch is already visible within the first postoperative year in 82% of these cases. Frequency and grade extension of the notch increase significantly with follow-up (p< 0.0001) but notch, when present, is not always evolutive. At this point of follow-up, scapular notch is not correlated with clinical outcome. There is a correlation with humeral radiolucent lines, particularly in metaphyseal zones (p=0.005) and with glenoid radiolucent lines around the fixation screws (p=0.006). Significant preoperative factors are: cuff tear arthropathy (p=0.0004), muscular fatty infiltration of infraspinatus (p=0.01), narrowing of acromio-humeral distance (p< 0.0001) and superior erosion of the glenoid (p=0.006). It was more frequent with superolateral approach than with deltopectoral approach (p< 0.0001) and with standard cup than with lateralized cup (p=0.02). We conclude that scapular notching is frequent, early and sometimes evolutive but not unavoidable. Preoperative superior glenoid erosion is significantly associated with a scapular notch, possibly due to the surgical tendency to position the baseplate with superior tilt and/or in high position which has been demonstrated to be an impingement factor. Preoperative radiographic planning and adapted glenoid preparation are of concern