Aims. The aim of this study was to report the outcomes of different treatment options for glenoid loosening following reverse shoulder arthroplasty (RSA) at a minimum follow-up of two years. Patients and Methods. We retrospectively studied the records of 79 patients (19 men, 60 women; 84 shoulders) aged 70.4 years (21 to 87) treated for aseptic loosening of the glenosphere following RSA. Clinical evaluation included pre- and post-treatment active anterior elevation (AAE), external rotation, and Constant score. Results. From the original cohort, 29 shoulders (35%) were treated conservatively, 27 shoulders (32%) were revised by revision of the glenosphere, and 28 shoulders (33%) were converted to hemiarthroplasty. At last follow-up, conservative treatment and glenoid revision significantly improved AAE, total Constant score, and pain, while hemiarthroplasty did not improve range of movement or clinical scores. Multivariable analysis confirmed that conservative treatment and glenoid revision achieved similar improvements in pain (glenoid revision vs conservative, beta 0.44; p = 0.834) but that outcomes were significantly worse following hemiarthroplasty (beta -5.00; p = 0.029). Conclusion. When possible, glenoid loosening after RSA should first be treated conservatively, then by glenosphere revision if necessary, and last by salvage hemiarthroplasty. Cite this article: Bone Joint J 2019;101-B:461–469

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

Reverse shoulder arthroplasty is becoming a frequent treatment of choice for patients with shoulder disorders. Complication rates after reverse shoulder arthroplasty may be three-fold that of conventional total shoulder arthroplasty especially in high risk patient populations and diagnoses like revision arthroplasty, fracture sequelae, and severe glenoid bone loss. Complications include component malposition, stiffness, neurological injury, infection, dislocation or instability, acromial or scapular spine fractures, scapular notching, and loosening of implants. Recognition of preoperative risk factors and appropriate 3D planning are essential in optimizing patient outcome and intraoperative success. Failure of reverse shoulder arthroplasty is a significant challenge requiring appropriate diagnosis of the failure mode. The most common neurological injuries involve the brachial plexus and the axillary nerve due to traction, manipulation of the arm, aberrant retractor placement, or relative lengthening of the arm. Intraoperative fractures are relatively uncommon but include the greater tuberosity, acromion, and glenoid. Tuberosity fracture can be repaired intraoperatively with suture techniques, glenoid fractures may be insignificant rim fractures or jeopardise baseplate fixation and require abandoning RSA until glenoid fracture ORIF heals and then a second stage RSA. Periprosthetic infection after RSA ranges from 1 to 10% and may be higher in revision cases and frequently is Propionibacterium acnes and Staphylococcus epidermidis. Dislocation was one of the most common complications after RSA approximately 5% but with increased surgeon experience and prosthetic design, dislocation rates are approaching 1–2%. An anterosuperior deltoid splitting approach has been associated with increased stability as well as subscapularis repair after RSA. Scapular notching is the most common complication after RSA. Notching may be caused by direct mechanical impingement of the humerosocket polyethylene on the scapular neck and from osteolysis from polyethylene wear. Sirveaux classified scapular notching based on the defect size as it erodes behind the baseplate towards the central post. Acromial fractures are infrequent but more common is severely eroded acromions from CTA, with osteoporosis, with excessive lengthening, and with superior baseplate screws that penetrate the scapular spine and create a stress riser. Nonoperative care is the mainstay of acromial and scapular spine fractures. Recognizing preoperative risk factors and understanding component positioning and design is essential to maximizing successful outcomes

Introduction. The use of reverse total shoulder arthroplasty (RSA) is becoming increasingly common in the treatment of rotator cuff arthropathy. Standard RSA technique involves medialising the centre of rotation (COR) maximising the deltoid lever arm and compensating for rotator cuff deficiency. However reported complications include scapular notching, prosthetic loosening and loss of shoulder contour. As a result the use of Bony Increased Offset Reverse Shoulder Arthroplasty (BIO-RSA) has been gaining in popularity. The BIO-RSA is reported to avoid these complications by lateralising the COR using a modified base plate, longer central post and augmentation with cancellous bone graft harvested from the patients humeral head. Objectives. This study aims to compare the outcome in terms of analgesic effect, function and satisfaction, in patients treated with standard RSA and BIO-RSA. Methods. All cases were performed in a single centre by one of two upper limb consultant orthopaedic surgeons over a consecutive 2-year period. At time of listing for operation, the decision as to whether to undertake a bony-increased offset reverse total shoulder was made. Standard deltopectoral approach was performed. Standard and Bony increased offset Tournier reverse was the implant of choice (BIO-RSA). All patients underwent a standardised rehabilitation programme. Standard follow up was clinical review with radiographs at 2 weeks, 6weeks and 3months. Retrospective data was collected using case notes on patient reported stausfaction and oxford shoulder score, analgesia requirement at final follow up, and final range of movement. Results. A total of 60 patients (65 shoulders) were treated with reverse total shoulder replacements (RSA) within a 2-year period in a single centre for chronic complex shoulder conditions. Mean age at time of intervention was 74.1years (49.3 – 88.7). Mean follow up was 7.1 months (3.4 – 24). Average time to discharge 16.1 months (3.4 – 37.4). 43 patients currently under review. Of the 65 shoulders, 40 underwent BIO-RSA procedures. Indications for surgery were predominantly rotator cuff arthropathy (N=36). Other indications included severe osteoarthritis (N=1) and complex proximal humeral fracture (N=3). The remaining 25 patients treated with standard RSA were similar in terms of indication and basic demographics. In terms of range of movement, outcomes between the two groups were broadly similar. Patients receiving BIO-RSA demonstrated mean active forward flexion of 92.2° (70–120°) and abduction 93.3° (80–120°). The RSA group had mean forward flexion 90.5° (50–130°) and mean abduction 88.6° (40–160°). Both groups had excellent analgesic effect with 92% in each either being completely pain free or requiring only occasional analgesia. The majority of patients were either very satisfied or satisfied with the outcome of the surgery. Mean Oxford shoulder score for the BIO-RSA group was 4.9 (0–13) preoperatively and 43.7 (36–48) postoperatively. The mean RSA pre-operative score was 7.9 (0–19) and postoperatively 40.2(32–48). In total three patients experienced complications; 1 haematoma (BIO-RSA), 1 brachial plexus contusion (BIO-RSA) and 1 deep infection (RSA). Conclusion. If grafting is necessary, the use of BIO-RSA within this centre seems to have comparable results to those undergoing standard RSA. Early results also suggest the Bio-RSA allows earlier improvement and conserves a larger bone stock. These early result are encouraging however a further study with longer follow-up is required

Aims. The purpose of this study was to evaluate the cost of reverse shoulder arthroplasty (RSA) for patients with a proximal humerus fracture, using time-driven activity based costing (TDABC), and to compare treatment costs with reimbursement under the Healthcare Resource Groups (HRGs). Methods. TDABC analysis based on the principles outlined by Kaplan and a clinical pathway that has previously been validated for this institution was used. Staffing cost, consumables, implants, and overheads were updated to reflect 2019/2020 costs. This was compared with the HRG reimbursements. Results. The mean cost of a RSA is £7,007.46 (£6,130.67 to £8,824.67). Implants and staffing costs were the primary cost drivers, with implants (£2,824.80) making up 40% of the costs. Staffing costs made up £1,367.78 (19%) of overall costs. The total tariff, accounting for market force factors and high comorbidities, reimburses £4,629. If maximum cost and minimum reimbursement is applied the losses to the trust are £4,828.67. Conclusion. RSA may be an effective and appropriate surgical option in the treatment of proximal humerus fractures; however, a cost analysis at our centre has demonstrated the financial burden of this surgery. Given its increasing use in trauma, there is a need to work towards generating an HRG that adequately reimburses providers. Cite this article: Bone Jt Open 2020;1-12:731–736

Hypothesis. Reverse shoulder arthroplasty has good mid-term results for rotator cuff deficient arthritic conditions. Methods and Analysis. 103 reverse shoulder arthroplasties were performed in 91 patients from January 2003 to September 2009. Twelve patients had bilateral reverse shoulder arthroplasties. Results. Average clinical follow-up was 13 months (range 3-72 months). There were 38% left and 62% right shoulders. Sixty-eight percent were women and 32% were men. The average age was 72 years (range 47-88 years). Indications included: rotator cuff arthropathies (79%), failed previous hemiarthroplasties and total shoulder arthroplasties (9%), rheumatoid arthritis (5%). Fractures accounted for 7% of cases, including acute 4-part fractures in the elderly, revision of fractures with deficient cuffs, malunion and nonunion cases with deficient cuffs. There was a significant improvement in quality of life. The Constant Score increased by an average of 46 points. 62 radiographs were reviewed. 75% of these showed notching of the inferior glenoid, 53% had notching of the posterior glenoid, 10 % had heterotrophic ossification inferior to the glenoid, and 40% had an inferior glenoid spur. Complications included: 2 dislocations, 1 massive heterotrophic ossification, 3 deep infections, 1 loose glenoid related to a fall, 3 acromial fractures, and 3 scapula spine fractures (all trauma related). Conclusion. Reverse shoulder arthroplasty is a good salvage procedure for cuff deficient arthritic conditions. Clinical mid-term results are good, but notching inferiorly and posteriorly may lead to deterioration over time. Fractures of the scapula appear to originate from either the superior or posterior screws which act as stress risers and an external rotation force of the greater tuberosity against the spine of the scapula in a fall may contribute to these fractures

Reverse Shoulder Arthroplasty (RSA) has been widely accepted for the treatment of rotator cuff arthropathy. There are a number of other shoulder pathologies where the reverse shoulder prosthesis can salvage previously untreatable shoulder conditions and restore function to the shoulder. This is a series of cases where RSA has been used to treat shoulder fractures. Material. Our indications for the reverse prosthesis in fracture management were:. Revision of failed fracture fixation with a deficient rotator cuff – 2 patients;. Acute 3 and 4 part fractures in the elderly, osteoporotic – 1 patient;. Acute 4 part fracture dislocation in elderly, osteoporotic – 1 patient;. Revision of non-union and malunions – 5 patients;. Revision of hemiarthroplasties which were initially done for fracture management – 5 patients. Results. There were a total of 14 cases treated for fractures out of 123 reverse shoulder arthroplasties performed. The average age for the fracture cases was 68 years (range 47–87) and for non-fracture RSA cases 73 years (range 51–88). The average follow-up Constant Score was 53 for fracture cases and 67 for non-fracture RSA cases. Complications included 1 dislocation and 1 deep infection. The problem with treatment of complex cases is there is an increased risk of complications. Problems encountered in the use of reverse shoulder arthroplasty in complex diagnoses include: instability, notching of scapula, scapula fractures, sepsis, lack of bone stock, poor quality soft-tissue and deficient deltoid muscle due to numerous previous surgical procedures, distortion of anatomy due to trauma, subscapularis deficiency and problems encountered from metal implants in situ. Conclusion. RSA is a good salvage procedure for cuff deficient shoulder fracture cases

The aim of the study was to assess the rate of greater tuberosity non union in reverse shoulder arthroplasty performed for proximal humerus fractures and to assess if union is related to type of fracture or the intraoperative reduction of the greater tuberosity. All cases of reverse shoulder arthroplasty for proximal humerus fractures at our institution over a three year period were retrospectively reviewed from casenotes and radiologically and the position of the greater tuberosity was documented at immediate post op, 6 months and 12 months. Any malunion or non union were noted. A total of 27 cases of reverse shoulder arthroplasty for proximal humeral fractures were identified. 4 cases did not have complete follow up xrays and were excluded from analysis. The average age at operation of the cohort of the 23 remaining patients was 79 years (range 70–91). The greater tuberosity was anatomically well positioned intraoperatively in 17 of the 23 cases. At the end of 12 months there were 4 cases of tuberosity non union (17%), all except one occurring in poorly intraoperatively positioned greater tuberosity. 50% (3 out of 6) of greater tuberosities displaced further and remained ununited if the intraoperative position was poor. Only 6% (1 out of 17) greater tuberosities did not unite if the greater tuberosities was reduced anatomically. Intra operatively position of the greater tuberosity was strongly associated with their union (Fischer's exact test p<0.05). Union of greater tuberosity was not statistically associated with fracture pattern (Fischer's exact test p=0.48). Our case series show a low rate of tuberosity malunion after reverse shoulder arthroplasty for proximal humerus fracture. Good positioning and fixation of the greater tuberosity intra operatively is a strong predictor of their uneventful union to shaft

Background:. While reverse shoulder arthroplasty has shown successful outcomes for a variety of shoulder pathologies, postoperative instability continues to be one of the most common complications limiting outcomes. In the literature, reports of instability range from 2.4%–31%. Many authors recommend an initial attempt at closed reduction followed by a period of immobilization for management of the initial dislocation episode while others may seek to rule out infection or other secondary causes; however there is little data to support either practice. The purpose of this study was to evaluate the outcomes of patients with postoperative dislocation following reverse shoulder arthroplasty managed with closed reduction. Methods:. A retrospective review of all reverse shoulder arthroplasties performed by a single surgeon (MF) from 2002-present was performed to identify all patients treated for postoperative dislocation treated with closed reduction, either in the office setting or under anesthesia in the operating room. A total of 21 patients were identified. Preoperative patient characteristics, implant selection, and time to initial dislocation episode were recorded. Final outcomes including recurrent instability need for revision surgery, ASES outcome score, and range of motion were evaluated. Results:. There were 9 male and 12 female patients. Nearly 50% (10/21) cases had previous surgery, with the vast majority of these being previous arthroplasty (8/10). The average time to first dislocation was 200 days (range: 2 days–961 days), with 62% (13/21) occurring in the first 90 days. At average follow-up of 28 months following the dislocation episode, 62% of these shoulders remained stable (13/21). Six shoulders (29%) required revision surgery for recurrent instability. The revision procedure included a larger glenosphere and socket in all cases. All of these patients remained stable at final follow-up (Ave 25.5 months). In those cases successfully treated with closed reduction the average time to dislocation was 188 days, whereas the average time to initial dislocation in cases requiring revision surgery was 224 days (p = 0.82). All of these patients remained stable at final follow-up. Two shoulders (9%) remained unstable and either declined or were medically unfit to undergo revision surgery. The average ASES score in patients treated with closed reduction for instability was 68.0, and 62.7 for those treated with revision surgery (p = 0.64). Conclusion:. This study shows that an initial dislocation episode following reverse shoulder arthroplasty can be successfully managed with closed reduction and temporary immobilization in over half of cases. The time to dislocation is not related to the likelihood of a successful closed reduction. Given that outcomes following revision surgery are not different from closed treatment we would continue to recommend an initial attempt at closed reduction in all cases of postoperative reverse shoulder arthroplasty dislocation

Reverse shoulder arthroplasty has a high complication rate related to glenoid implant instability and screw loosening. Better radiographic post-operative evaluation may help in understanding complications causes. Medical radiographic imaging is the conventional technique for post-operative component placement analysis. Studies suggest that volumetric CT is better than use of CT slices or conventional radiographs. Currently, post-operative CT use is limited by metal-artifacts in images. This study evaluated inter-observer reliability of pre-operative and post-operative CT images registration to conventional approaches using radiographs and CT slices in measuring reverse shoulder arthroplasty glenoid implant and screw percentage in bone. Pre-operative and post-operative CT scans, and post-operative radiographs were obtained from six patients that had reverse shoulder arthroplasty. CT scans images were imported into a medical imaging processing software and each scapula, glenoid implant and inferior screw were reconstructed as 3D models. Post-operative 3D models were imported into the pre-operative reference frame and matched to the pre-operative scapula model using a paired-point and a surface registration. Measurements on registered CT models were done in reference to the pre-operative scapula model coordinate frame defined by a computer-assisted designed triad positioned in respect to the center of the glenoid fossa and trigonum scapulae (medial-lateral, z axis) and superior and inferior glenoid tubercle (superior-inferior, y axis). The orthogonal triad third axis defined the anterior-posterior axis (x axis). A duplicate triad was positioned along the central axis of the glenoid implant model. Using a virtual protractor, the glenoid implant inclination was measured from its central axis and the scapula transverse plane (x - z axes) and version from the coronal plane (y - z axes). Inferior screw percentage in bone was measured from a Boolean intersection operation between the pre-operative scapula model and the inferior screw model. For CT slices and radiographic measurements, a first 90-degree Cobb angle, from medical records software, was positioned from the trigonum scapulae to the centre of the central peg. Using the 90-degree line as reference, a second Cobb angle was drawn from the most superior to the most inferior point of the glenoid implant for inclination and from of the most anterior to the most posterior point for version. Version can only be measured using CT slices. Screw percentage in bone was calculated from screw length measures collected with a distance-measuring tool from the software. For testing the inter-observer reliability of the three methods, measures taken by three qualified observers were analysed using an intra-class correlation coefficient (ICC) method. The 3D registration method showed excellent reliability (ICC > 0.75) in glenoid implant inclination (0.97), version (0.98) and screw volume in bone (0.99). Conventional methods showed poor reliability (ICC < 0.4); CT-slice inclination (0.02), version (0.07), percentage of screw in bone (0.02) and for radiographic inclination (0.05) and percentage screw in bone (0.05). This CT registration of post-operative to pre-operative novel method for quantitatively assessing reverse shoulder arthroplasty glenoid implant positioning and screw percentage in bone, showed excellent inter-observer reliability compared to conventional 2D approaches. It overcomes metal-artifact limitations of post-operative CT evaluation

Scapular notching is a common problem following reverse shoulder arthroplasty (RSA). This is due to impingement between the humeral polyethylene cup and scapular neck in adduction and external rotation. Various glenoid component strategies have been described to combat scapular notching and enhance impingement-free range of motion (ROM). There is limited data available detailing optimal glenosphere position in RSA with an onlay configuration. The purpose of this study was to determine which glenosphere configurations would maximise impingement free ROM using an onlay RSA prosthesis. A three-dimensional (3D) computed tomography (CT) scan of a shoulder with Walch A1, Favard E0 glenoid morphology was segmented using validated software. An onlay RSA prosthesis was implanted and a computer model simulated external rotation and adduction motion of the virtual RSA prosthesis. Four glenosphere parameters were tested; diameter (36mm, 41mm), lateralization (0mm, 3mm, 6mm), inferior tilt (neutral, 5 degrees, 10 degrees), and inferior eccentric positioning (0.5mm, 1.5mm. 2.5mm, 3.5mm, 4.5mm). Eighty-four combinations were simulated. For each simulation, the humeral neck-shaft angle was 147 degrees and retroversion was 30 degrees. The largest increase in impingement-free range of motion resulted from increasing inferior eccentric positioning, gaining 15.0 degrees for external rotation and 18.8 degrees for adduction. Glenosphere lateralization increased external rotation motion by 13. 6 degrees and adduction by 4.3 degrees. Implanting larger diameter glenospheres increased external rotation and adduction by 9.4 and 10.1 degrees respectively. Glenosphere tilt had a negligible effect on impingement-free ROM. Maximizing inferior glenosphere eccentricity, lateralizing the glenosphere, and implanting larger glenosphere diameters improves impingement-free range of motion, in particular external rotation, of an onlay RSA prosthesis. Surgeons’ awareness of these trends can help optimize glenoid component position to maximise impingement-free ROM for RSA. Further studies are required to validate these findings in the context of scapulothoracic motion and soft tissue constraints

The reverse ball and socket shoulder replacement, employing a humeral socket and glenosphere, has revolutionized the treatment of patients with arthritis and rotator cuff insufficiency. The RSP (DjO Surgical, Inc., Austin, Texas) is one such device, characterized by a lateral center of rotation and approved for use in the United States since 2004. Multiple studies by the implant design team have documented excellent outcomes and low revision rates for the RSP, but other published outcomes data are relatively sparse. The objective of this study is to report on the complications and early outcomes in the first consecutive 60 RSPs implanted in 57 patients by a single shoulder replacement surgeon between 2004 and 2010. Forty-four patients were female and mean age at the time of reverse shoulder arthroplasty was 75 years (range 54 to 92 years). The RSP was used as a primary arthroplasty in 42 shoulders and to revise a failed prosthetic shoulder arthroplasty in 18 shoulders. During the study period, 365 shoulder replacements were implanted so that the RSP was used selectively, accounting for only 17% of all shoulder arthroplasties (8.4% for 2004-2007, 24.2% for 2008-2010). Most patients had pseudoparalysis and profound shoulder dysfunction so that mean pre-operative active forward elevation was to 45°, active abduction to 43°, active internal rotation to the buttock, and the mean pre-operative Simple Shoulder Test (SST) score was 1 out of 12. At final follow-up, mean active forward elevation had improved to 101° (p<0.0001), active abduction to 91° (p<0.0001), active internal rotation to the lumbosacral junction (p<0.001), and the mean final SST score was 7 out of 12. There were 16 complications in 14 patients, including 7 reoperations in 6 patients (11%): 3 closed reductions for dislocation, 2 open revisions for instability and for a dissociated liner in the same patient, one evacuation of a hematoma, and one open reduction and internal fixation of a post-operative scapular spine fracture. Two additional scapular spine or acromion fractures and one acromioclavicular joint separation developed postoperatively that impacted outcome adversely but did not require re-operation. None of the glenoid baseplates or humeral stems has been revised and no deep infections have occurred. Experience with reverse shoulder arthroplasty appears to influence the reoperation rate, as 3 of the reoperations occurred following the first 15 reverse shoulder arthroplasties. Overall improvements in active motion and self-assessed shoulder function were comparable to those reported previously. Final active motion results were somewhat lower than those reported previously, which may relate to the selection of predominately pseudoparalytic patients for reverse shoulder arthroplasty in this series. Use of the RSP device for reverse shoulder arthroplasty leads to improved motion and function in carefully selected older patients with pseudoparalysis or a failed shoulder replacement. Re-operations and complications occur but the learning curve may not be as steep as previously reported. This may relate to specific features of the implant system used in this series, as well as to surgeon experience

Introduction. Reverse shoulder Arthroplasty is a successful treatment for gleno-humeral osteoarthritis. However, components loosening and painful prostheses, related to components wrong positioning, are still a problem for those patients who underwent this kind of surgery. Several new technology has been developed the improve the implant positioning. CT-based intraoperative navigation system is a suitable technology that allow the surgeon to prepare the implant site exactly as planned with preoperative software. Method. Thirty reverse shoulder prostheses were performed at Modena Polyclinic using GPS CT-based intraoperative navigation system (Exactech, Gainsville, Florida). Walch classification was used to assess glenoid type. Planned version and inclination of the glenoid component, planned seating, final version and inclination of the reamer were recorded. Intraoperative and perioperative complication were recorded. Planned positioning was conducted aiming to the maximum seating, avoiding retroversion >10° and superior inclination. Results. Eight patients were male, 22 were female. Mean age was 75 years old (range 58–87). 4 glenoid were type B3, four were B2, 10 cases were B1, 12 case were A1/A2. Posterior or superior augment was used in 15 cases. Mean planned seating was 93%. Mean preoperative version was -7.5±6.9°; Mean planned version was -2±2.8°; Mean intraoperative measured version was -1.9±2.8°; no statistical difference was found between planned and intraoperative version (p=0.16). Mean preoperative inclination was 1.8±6.°; Mean planned inclination was -2.2±2.4°; Mean intraoperative measured inclination was -2.1.9±2.3°; no statistical difference was found between planned and intraoperative version or inclination (respectively p=0.16 and p=0.32). Mean surgical time was 71 minute (range 51–82). Three cases of coracoid ruptures were reported, 1 failure of the system occurred. Discussion. GPS navigation system allows the surgeon to prepare the implant site as planned on Preoperative software in Reverse shoulder arthroplasty, with no statistical difference between planned orientation and intraoperative measured orientation. That means that even in the most difficult cases the surgeon is able to find a good positioning (93% seating)and to replicate it in the operative room. Only one failure of the system occurred, because too much time was passed between CT scan and surgery (9 months). Three coracoid fractures occurred in the first 10 cases: these could be addressed to a lack of confidence with the double lateralization of this prosthesis which increase tensioning on the coracoid and a lack of confidence in tracker positioning, which should be made as proximal as it is possible. Finally, the system needs several improvements to be considered a breakthrough technology, such as humeral component positioning and final control of the implant, but by now is a useful way to improve our surgery, especially in difficult cases

In reverse shoulder arthroplasty (RSA), a high complication rate is noted in the international literature (24.7%), and limited local literature is available. The complications in our developing health system, with high HIV, tuberculosis and metabolic syndrome prevalence may be different from that in developed health systems where the literature largely emanates from. The aim of this study is to describe the complications and complication rate following RSA in a South African cohort. An analytical, cross-sectional study was done where all patients’ who received RSA over an 11 year period at a tertiary hospital were evaluated. One-hundred-and-twenty-six primary RSA patients met the inclusion criteria and a detailed retrospective evaluation of their demographics, clinical variables and complication associated with their shoulder arthroplasty were assessed. All fracture, revision and tumour resection arthroplasties were excluded, and a minimum of 6 months follow up was required. A primary RSA complication rate of 19.0% (24/126) was noted, with the most complications occurring after 90 days at 54.2% (13/24). Instability was the predominant delayed complication at 61.5% (8/13) and sepsis being the most common in the early days at 45.5% (5/11). Haematoma formation, hardware failure and axillary nerve injury were also noted at 4.2% each (1/24). Keeping in mind the immense difference in socioeconomical status and patient demographics in a third world country the RSA complication rate in this study correlates with the known international consensus. This also proves that RSA is still a suitable option for rotator cuff arthropathy and glenohumeral osteoarthritis even in an economically constrained environment like South Africa

Reverse shoulder arthroplasty has been used to treat arthritis of the shoulder with no rotator cuff. The purpose of this study is to review the short term outcome of reverse shoulder arthroplasty performed at North Shore Hospital. Between 2003 and 2007, 54 consecutive patients were treated with the SMR reverse shoulder prosthesis. Patients were assessed using the visual analogue pain score, patient satisfaction rating, the American Shoulder and Elbow Society Shoulder score, the Oxford shoulder score, the Short Form – 12, and by radiographs. We also reviewed clinical and radiographic complications. Nine patients underwent surgery for fracture, two for chronic dislocation and 43 for cuff tear arthropathy, including four revisions. The mean age at surgery was 77.8 years (range 54–91 years). 53 of the implanted prostheses were SMR (Lima Orthotec) and one was a Delta (De Puy). Patient assessment is still in progress, but findings so far show very favourable early outcomes. We report a large consecutive series of patients who had the reverse prothesis at North Shore hospital. To the best of our knowledge, there has been no previous publication of results of the SMR reverse prosthesis

Crosby and Colleagues described 24 scapula fractures in 400 reverse shoulder arthroplasties and classified scapula fractures after reverse shoulder arthroplasty into 3 types. Type 1 – true avulsion fracture of acromion related to a thinned out acromion (post-acromioplaty or cuff arthropathy). A small bone fragment dislodges during reduction of RSA. Type 2 – Acromial fracture due to Acromio-clavicular (AC) joint arthrosis. They feel the lack of movement at the AC joint leads to stresses across the acromion and cause it to fracture. They recommend AC joint resection and ORIF of acromion, if the acromion is unstable. Type 3 – true scapula spine fracture caused by the superior screw acting as a stress riser. This fracture occurs about 8 months after the arthroplasty and is a true stress fracture requiring open reduction and internal fixation. Of 123 reverse shoulder arthroplasties performed from Jan 2003 to Feb 2011, a total of 6 scapula fractures were encountered post-surgery. Three were acromial fractures and three were scapula spine fractures all related to trauma. The fractures of the spine occurred between 6 months and 4 years post arthroplasty. We feel the fractures were traumatic but did occur through the posterior or superior screws from the metaglen. where stress risers developed for a fracture to occur. We found that using a sliding osteotomy of the spine of the scapula to bridge the defect of the scapula and a double-plating technique using two plates at 90 degrees to each other provides a satisfactory outcome after 3–6 months where patients can start actively elevating again. This method of treatment will be presented

Abstract. Background. The influence of diagnosis on outcomes after reverse shoulder arthroplasty (RSA) is not completely understood. The purpose of this study was to compare clinical outcomes of different pathologies. Methods. A total of 78 RSAs were performed for the following diagnoses: (1) rotator cuff tear arthropathy(RCA), (2) massive cuff tear(MCT) with osteoarthritis(OA), (3) MCT without OA, (4) arthritis, (5) acute proximal humerus fracture. Mean follow up 36 months (upto 5 years) Range of motion, Oxford Shoulder Score were obtained preoperatively and postoperatively. Results. Mean OSS was 30. The RCA, MCT-with-OA, MCT-without-OA, and arthritis groups all exhibited significant improvements in all outcome scores and in all planes of motion. After adjustment for age and compared with RCA, those with OA had significantly better abduction (P < .05), and those with fractures had significantly worse patient satisfaction (P < .05). Among male patients, those with MCTs without OA had significantly worse satisfaction (P < .05). Conclusion. RSA reliably provides improvement regardless of preoperative diagnosis. Although subtle differences exist between male and female patients, improvements in clinical outcome scores were apparent after RSA

Although, reverse shoulder arthroplasty has initially been introduced for rotator cuff arthropathy, its application has been expanded on fracture sequelae, chronic dislocations and even comminuted fractures of the humeral head in elderly patients. The purpose of this study is to present our experience and the mid-term clinical results of this type prosthesis. Between 2006 and 2008 16 reverse shoulder arthroplasties have been carried out in our department. Fourteen patients were female and 2 male with an average age of 72.4 years (55–81). Eleven patients had true rotator cuff arthropathy, 3 malunion of 4-part fractures, one chronic anterior shoulder dislocation and finally one patient had bilateral chronic posterior shoulder dislocation. In 2 cases we used the Delta prosthesis and in a further 14 cases the Aquealis Arthroplasty. Routine postoperative follow up was at 3,6,12 and 24 months and included plain radiographic control and clinical evaluation with the Constant Shoulder Score. All patients report significant pain relief and an average improvement of the Constant Score from 40.5 to 72.3. Two patients had anterior dislocation of the prosthesis 4 days postoperatively and we proceeded to the application of a 9 mm metal spacer and bigger polyethylene size. In one patient neuroapraxia of the axillary nerve was observed; this resolved 3 months postoperatively. Continuous clinical improvement was observed in some patients up until 18 months postoperatively. Our clinical results are very satisfactory and reveal that reverse shoulder arhroplasty is a very good option for a broad spectrum of pathologic shoulder conditions

Reverse shoulder arthroplasty (RSA) is commonly used to treat patients with rotator cuff tear arthropathy. Loosening of the glenoid component remains one of the principal modes of failure and is the main complication leading to revision. For optimal RSA implant osseointegration to occur, the micromotion between the baseplate and the bone must not exceed a threshold of 150 µm. Excess micromotion contributes to glenoid loosening. This study assessed the effects of various factors on glenoid baseplate micromotion for primary fixation of RSA. A half-fractional factorial experiment design (2k-1) was used to assess four factors: central element type (central peg or screw), central element cortical engagement according to length (13.5 or 23.5 mm), anterior-posterior (A-P) peripheral screw type (nonlocking or locking), and bone surrogate density (10 or 25 pounds per cubic foot [pcf]). This created eight unique conditions, each repeated five times for 40 total runs. Glenoid baseplates were implanted into high- or low-density Sawbones™ rigid polyurethane (PU) foam blocks and cyclically loaded at 60 degrees for 1000 cycles (500 N compressive force range) using a custom designed loading apparatus. Micromotion at the four peripheral screw positions was recorded using linear variable displacement transducers (LVDTs). Maximum micromotion was quantified as the displacement range at the implant-PU interface, averaged over the last 10 cycles of loading. Baseplates with short central elements that lacked cortical bone engagement generated 373% greater maximum micromotion at all peripheral screw positions compared to those with long central elements (p < 0.001). Central peg fixation generated 360% greater maximum micromotion than central screw fixation (p < 0.001). No significant effects were observed when varying A-P peripheral screw type or bone surrogate density. There were significant interactions between central element length and type (p < 0.001). An interaction existed between central element type and level of cortical engagement. A central screw and a long central element that engaged cortical bone reduced RSA baseplate micromotion. These findings serve to inform surgical decision-making regarding baseplate fixation elements to minimize the risk of glenoid loosening and thus, the need for revision surgery

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