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Adequate exposure in revision of total shoulder arthroplasty (TSA) is important for optimal prosthesis placement and functional results. A clavicular osteotomy in difficult cases of revision TSA is a useful surgical technique that increases the superior exposure area, provides safer dissection, minimizes damage to the anterior deltoid muscle, improves glenoid access, and allows for superior dislocation of the humeral component. There is a paucity of literature analyzing the clavicular osteotomy during challenging cases of revision TSA. The aims of this study were to describe the application, surgical technique, and outcomes of revision TSA with a clavicular osteotomy. This was a retrospective study of consecutive patients who underwent revision TSA with a clavicle osteotomy at a single institution (2004–2016). A curved longitudinal clavicular osteotomy is created parallel to the origin of the anterior deltoid muscle. This allows for lateral reflection of the osteotomy and anterior deltoid muscle to significantly increase superior exposure and reduce damage to remaining deltoid muscle fibres. Osteotomy closure is simple with four or five Nice knot osteosutures. The Constant-Murley score and osteotomy healing were assessed at every follow-up. All complications were reviewed. Forty patients who had a mean age of 63.8 years (range 37–87) at time of surgery and mean follow-up duration of 34 months (range 12–88) were analyzed. Pre-operative Constant-Murley scores improved significantly from 32 ± 19.0 to 58 ± 15.0 (p

Although degenerative osteoarthritis of the acromioclavicular joint is a common finding on technical investigations, not every patient experiences pain or function loss. The difference between symptomatic and asymptomatic patients is currently not elucidated. Therefore, we want to investigate the acromioclavicular relationship in normal, asymptomatic, and symptomatic degenerated ACJ. 84 normal ACJ, 39 asymptomatic degenerated ACJ, and 30 symptomatic degenerated ACJ were 3D reconstructed. The morphological dimensions and the relationship of the acromion and distal clavicle were measured using computational software. The reproducibility of this technique was evaluated using inter- and intra-observer reliability. The mean anteroposterior and superoinferior distance of both the clavicle and acromion was significantly larger in asymptomatic and symptomatic degenerative ACJ compared to the normal ACJ (p

Reverse shoulder arthroplasty has become the standard treatment for cuff tear arthropathy and complex fractures of the proximal humerus. The Delta Xtend prosthesis (DePuy Synthes, Warsaw, IN, USA) was launched in 2006 and has shown good short-term results. Longer-term results are not yet available.There were 126 primary Delta Xtend prostheses implanted in our center by 1 surgeon from October 2006 until December 2009. Of these, 38 patients died, 12 were lost to follow-up, and 2 needed early revision of the prosthesis. Follow-up of at least 8 years was available for 74 patients. At preoperative and postoperative visits, shoulder function and pain were evaluated using the age- and sex-adjusted Constant-Murley score (aCS). The satisfaction rate was evaluated on a visual analog scale (VAS).The mean follow-up in our population was 113.1 months. The mean aCS was 44.6% (standard deviation [SD], 19.2) preoperatively. It increased significantly (P .001) after surgery to 75.8% (SD, 12.5) at 3 months and 91.1% (SD, 11.8) at 5 years. At the latest follow-up, the mean aCS was only 79.9% (SD, 17.7), which was significantly lower (P = .002) than the aCS at 5 years postoperatively. An overall survival rate of more than 97% was seen at 8 years of follow-up.This study confirms that the promising short-term results of the Delta Xtend prosthesis can be extended in the longer-term. However, further follow-up will be necessary to check whether the statistically significant decrease in the Constant-Murley score at latest follow-up, which was driven by a decrease in range of motion and power, continues or not.

Background: Patients with an uncontained glenoid bone defect can still successfully undergo a reverse total shoulder arthroplasty (RTSA). Currently, there is a tendency toward reconstruction of the premorbid glenoid plane with bone grafts, which is technically demanding. We investigated whether central peg positioning in the spine pillar (CPPSP) is a more feasible alternative to the use of bone grafts. Methods: This study included 60 revisions to an RTSA with uncontained glenoid bone defects. Patients were treated with bone grafts in 29 cases and with the CPPSP technique in 31 cases. We assessed clinical results using the Constant score and assessed the complication rate. Results: The Constant score changed from 42 to 69 points in the CPPSP group and from 47 to 60 points in the bone graft group. This difference in the increase in the Constant score was significant (P = .031) owing to a significant difference in strength in favor of the CPPSP group. The overall complication rate was 37.7% (20 of 53 patients), with a reoperation rate of 18.9% (10 of 53). Dislocations occurred only in the CPPSP group (n = 3), and loosening of the glenoid occurred only in the bone graft group (n = 3). Conclusion: Patients with uncontained glenoid bone defects undergoing revision to an RTSA obtain similar clinical results with the CPPSP technique compared with the use of bone grafts. The CPPSP technique is a valid alternative but results in different complications. (C) 2020 Journal of Shoulder and Elbow Surgery Board of Trustees. All rights reserved.

Patients with complex regional pain syndrome (CRPS) report cognitive difficulties, affecting the ability to represent, perceive and use their affected limb. Moseley, Gallace & Spence (2009) observed that CRPS patients tend to bias the perception of tactile stimulation away from the pathological limb. Interestingly, this bias was reversed when CRPS patients were asked to cross their arms, implying that this bias is embedded in a complex representation of the body that takes into account the position of body-parts. Other studies have failed to replicate this finding (Filbrich et al., 2017) or have even found a bias in the opposite direction (Sumitani et al., 2007). Moreover, perceptual biases in CRPS patients have not often been compared to these of other chronic pain patients. Chronic pain patients are often characterized by an excessive focus of attention for bodily sensations. We might therefore expect that non-CRPS pain patients would show a bias towards instead of away from their affected limb. The aim of this study was to replicate the study of Moseley, Gallace & Spence (2009) and to extend it by comparing perceptual biases in a CRPS group with two non-CRPS pain control groups (i.e., chronic unilateral wrist and shoulder pain patients). In a temporal order judgment (TOJ) task, participants reported which of two tactile stimuli, one applied to either hand at various intervals, was perceived as occurring first. TOJs were made, either with the arms in a normal (uncrossed) position, or with the arms crossed over the body midline. We found no consistent perceptual biases in either of the patient groups and in either of the conditions (crossed/uncrossed). Individual differences were large and might, at least partly, be explained by other variables, such as pain duration and temperature differences between the pathological and non-pathological hand. Additional studies need to take these variables into account by, for example, comparing biases in CRPS (and non-CRPS) patients in an acute versus a chronic pain state.

Background The etiology of tennis elbow is multifactorial. Overuse of the wrist extensors along with anatomic factors, such as flexibility problems, aging, and poor blood circulation, may play a role. This study investigated whether patients with tennis elbow have a different psychological profile compared with healthy controls. Methods Patients with clinical signs of tennis elbow, consulting at the Ghent University Hospital between September 2015 and January 2017, were offered a paper-and-pencil questionnaire about Big Five personality traits, perfectionism, anxiety, depression, work satisfaction, and working conditions. Healthy controls in the same risk group were offered the same questionnaires. Results We recruited 69 patients (35 men, 34 women) and 100 controls (44 men, 56 women). Tennis elbow patients scored significantly lower on the personality traits extraversion and agreeableness. Men, in particular, scored significantly higher on perfectionism and were more likely to develop an anxiety disorder or a depression. Concerning work, patients indicated a significantly higher workload (especially men) and a significantly lower autonomy (especially women). Female patients also indicated less contact with colleagues. However, work satisfaction was relatively high in both groups. Conclusion The results suggest that there is a relationship between complaints related to tennis elbow and psychological characteristics.

Background The humeral subluxation index (HSI) is frequently assessed on computed tomography (CT) scans in conditions of the shoulder characterized by humeral displacement. An arbitrarily set HSI cutoff value of 45% for anterior subluxation and 55% for posterior subluxation has been widely accepted. We studied whether mean values and thresholds of humeral subluxation, in relation to the glenoid and scapula, were influenced by different imaging modalities. Methods The HSIs referenced to the scapula (SHSI) and glenoid (GHSI) were compared between conventional CT scans, CT scans reoriented into the corresponding reference plane (ie, scapular plane for the SHSI and glenoid center plane for the GHSI), and 3-dimensional (3D) CT reconstructions of 120 healthy shoulders. The 95% normal range determined the cutoff values of humeral subluxation. Results The SHSI thresholds for conventional, reoriented, and 3D CT scans were 33%-61%, 44%-68%, and 49%-61%, respectively. A different mean SHSI was found for each imaging modality (conventional, 47%; reoriented, 56%; 3D, 55%; P ≤ .014), with the conventional SHSI showing an underestimation in 89% of the cases. GHSI thresholds for conventional, reoriented, and 3D CT scans were 40%-61%, 44%-56%, and 46%-54%, respectively. The mean GHSI did not differ between each imaging modality (conventional, 51%; reoriented, 50%; 3D, 50%; P = .146). Conclusions The SHSI and GHSI are susceptible to different imaging modalities with consequently different cutoff values. The redefined HSI cutoff values guide physicians in the evaluation of humeral subluxation in conditions characterized by humeral displacement, depending on the available image data.

Background The most commonly used repair techniques to treat an acromioclavicular dislocation imply a suspension mechanism by substituting the supero-inferior oriented coracoclavicular structures with a tight rope mechanism or allograft. Recently, the importance of restoring the antero-posterior stability by addressing the acromioclavicular structures has also been demonstrated. If an in situ repair at the acromioclavicular joint itself could achieve a reposition and would be strong enough, the suspension of the CC structures might become obsolete. Possible advantages would be minimal dissection, lower risk in damaging neurovascular structures, greater stability, reduction of the surgical time and even the possibility of locoregional anesthesia. Hypothesis In this biomechanical study, the feasibility of different in situ repair techniques is explored thereby testing both compression and translation characteristics. Our hypothesis is that an in situ repair technique results in an adequate repair for the AC joint. Methods and materials Polyurethane foam blocks will be used as a model for the acromioclavicular joint and the repair techniques will be done by using a combination of sutures and bone anchors or using a transosseous technique. Compression will be measured by means of a Tekscan pressure sensor and translation will be tested in three orthogonal directions using a tensile testing machine. Four different knot anchor configurations (nice knot, surgical knot in two different configurations, Nicky's knot) will be tested for compression. The strongest knot anchor configuration will then be compared side to side with a transosseous configuration for translation. Results The nice knot in combination with bone anchors provides the strongest compression. In the side to side comparison of a nice knot anchor configuration versus a transosseous nice knot configuration, the transosseous technique shows more resistance to translation. Discussion An in situ repair by a combination of the nice knot with an anchor or a transosseous nice knot configuration can theoretically be used as a repair technique for an acromioclavicular dislocation. In comparison with existing techniques, this model shows favorable results for translation. Level of evidence III, controlled laboratory study.

Cerclage techniques are simple, yet effective techniques to treat certain fractures and are known as one of the first operative techniques in orthopaedic surgery. The days when a twisted metal wire was the only available cerclage technique nonetheless have passed and today there are many different materials and techniques available. This review evaluates the differences between metallic and non-metallic cerclage techniques, thereby looking at biomechanical, technical and biological aspects. It also provides an overview of clinical applications for non-metallic cerclages. The use of metallic versus non-metallic cerclage might differ depending on indication, location and involved tissues. Currently metallic cerclage is mostly used to repair fractures because of its believed higher absolute strength. More recently though, non-metallic cerclage has been proven to withstand the same loads, while having a lower complication rate. This review suggests that mainly in the upper limb a non-metallic cerclage technique might become the golden standard, while in the lower limb both metallic and non-metallic cerclage techniques are complementary and dependent on indication.

Background Glenoid dissociation is a rare postoperative complication in reverse shoulder arthroplasty that has severe consequences for the patient and requires revision in most cases. A mechanically compromised Morse taper is hypothesized to be the main cause of this complication, with bony impingements and soft tissue interpositioning being cited as the most important problems. Intraoperative assessment of the taper assembly is challenging. Current methods require applying considerable torque to the glenosphere or relying on radiographs. Materials and methods This in vitro study demonstrates how the assembly quality can be accurately determined in a nondestructive way by exploiting the implant-specific relation between screw and Morse taper characteristics by measuring the angular rotation–torque curve. Results The feasibility of the method is demonstrated on 2 reverse implant models. Several data features that can statistically discriminate between optimal and suboptimal assemblies are proposed. Conclusion Suboptimal assemblies can be detected using the method presented, which could easily be integrated in the current surgical workflow. Clinical recommendations based on the method's rationale are also presented, allowing detection of the most severe defect cases with surgical instruments currently in use.

Introduction Despite the ever-increasing popularity of bicycle racing, the high perceived risk of acute injuries and the recent media attention, studies of acute injuries in road cyclists are rather scarce. The goal of this study is to evaluate the incidence, aetiology and patterns of acute injuries in non-professional competitive road cyclists during cycling races in Flanders. Material and methods All acute injuries that occurred during competition in Flanders in 2002 and 2012, collected in the injury registry, were analysed. The incidence, injury rate, diagnosis, circumstances and level of performance were evaluated. Results A total of 777 documented reports of accidents (1230 injuries) were retrieved for the years 2002 and 2012. There was no significant difference between incidence and injury rate between 2002 and 2012. There was a strong significant difference in the incidence between the different levels of performance in both seasons. Severe injuries were seen in 29.5% in 2002 and in 30.1% in 2012. The most common location of a severe injury was the hand. Collision with another rider was the most common cause of injury. Conclusions Almost 1 out of 6 non-professional competitive road cyclists had an accident during cycling races in 2002 and 2012 in Flanders and collision with other riders was the most important cause of a crash. The most common lesion was abrasion, but almost one out of three riders had a severe injury.

Clinical shoulder science lacks a benchmark against which the early clinical value of new glenoid components can be compared; such a benchmark may be derived from a multicenter study of patients receiving an established, internationally used design of glenoid component. We obtained data from 11 centers on 1270 patients having total shoulder arthroplasty using an all-polyethylene component with a fluted central peg. We analyzed individual patient outcomes at 1 and 2 years after surgery. We compared the improvement for each patient to the minimal clinically important difference (MCID) and calculated each patient’s improvement as a percent of maximal possible improvement (MPI). The preoperative scores improved from SST 3 ± 2, ASES 37 ± 15, Constant score 36 ± 16, and Penn score 30 ± 19 to SST 10 ± 2, ASES 90 ± 12, Constant 76 ± 13, and Penn 80 ± 24 (p

Despite good clinical results and low recurrence rates, post-operative complications of coracoid process transfer procedures are not well understood. This study aims to evaluate the underlying failure mechanism in cases requiring major open revision surgery after prior Bristow or Latarjet stabilization. Between January 2006 and January 2017, 26 patients underwent major open revision after primary Bristow or Latarjet procedure. Clinical notes and radiographic images were retrospectively reviewed for all cases to determine underlying pathology. Choice of treatment and clinical and radiographic outcome were similarly reported for all cases. The underlying failure mechanism was associated with non-union in 42.3%, resorption in 23.1%, graft malpositioning in 15.4%, and trauma or graft fracture in 19.2% of cases. Although none of the patients reported any dislocations, mean subjective shoulder score was 60.2% and WOSI scores averaged 709.3 points at final follow-up. Radiographic signs of deteriorating degenerative arthritis were seen in 34.6%. Graft non-union resulting in recurrent instability was the main indication for open revision surgery after Bristow or Latarjet procedure, followed by resorption, malpositioning, and graft fracture in this retrospective case series. Revision surgery consisted of a structural iliac crest bone graft in the majority of cases. Clinical and radiographic outcomes are predictably variable in this population of multioperated patients.

Reversed total shoulder arthroplasty is a popular treatment in rotator cuff arthropathy and in displaced proximal humeral fractures in elderly. In 2016, 29 models of commercially available designs express this popularity. This study describes all the different design parameters available on the market. Prosthetic differences are found for the baseplate, glenosphere, polyethylene, and humeral component and these differences need to be weighed out carefully for each patient knowing that a gain in one mechanical parameter can balance the loss of another. Patient specific implants may help in the future.

Background Abnormal glenoid version positioning has been recognized as a cause of glenoid component failure caused by the rocking horse phenomenon. In contrast, the importance of the glenoid inclination has not been investigated. Materials and methods The computed tomography scans of 152 healthy shoulders were evaluated. A virtual glenoid component was positioned in 2 different planes: the maximum circular plane (MCP) and the inferior circle plane (ICP). The MCP was defined by the best fitting circle of the most superior point of the glenoid and 2 points at the lower glenoid rim. The ICP was defined by the best fitting circle on the rim of the inferior quadrants. The inclination of both planes was measured as the intersection with the scapular plane. We defined the force vector of the rotator force couple and calculated the magnitude of the shear force vector on a virtual glenoid component in both planes during glenohumeral abduction. Results The inclination of the component positioned in the MCP averaged 95° (range, 84°-108°) and for the ICP averaged 111° (range, 94°-126°). A significant reduction in shear forces was calculated for the glenoid component in the ICP vs the MCP: 98% reduction in 60° of abduction to 49% reduction in 90° of abduction. Conclusion Shear forces are significantly higher when the glenoid component is positioned in the MCP compared with the ICP, and this is more pronounced in early abduction. Positioning the glenoid component in the inferior circle might reduce the risk of a rocking horse phenomenon.

Correction of posterior humeral subluxation, measured by the humeral subluxation index (HSI) according to Walch, is necessary in total shoulder arthroplasty to prevent early loosening. The 3-dimensional (3D) measurement of the shoulder is becoming well accepted and common practice as it overcomes positional errors to which 2-dimensional (2D) glenohumeral measurements are prone. The first objective was to describe the HSI in a nonpathologic population with the 2D HSI according to Walch and a newly described 3D HSI method. The second objective was to compare both measuring methods with each other.In 151 nonpathologic shoulders, the 2D HSI was measured on the midaxial computed tomography scan cut of the scapula. The 3D HSI, based on the native glenoid plane, was defined as [formula in text], in which X is the projection of the center of the humeral head to the anteroposterior axis of the glenoid fossa and R is the radius of the humeral head. Both measuring methods were compared with each other. Correlation was determined. Interobserver and intraobserver reliability of the 3D HSI was measured.The mean 3D HSI (51.5% ± 2.7%) was significantly (P.001) more posterior than the mean 2D HSI (48.7% ± 5.2%), with a mean difference of 2.9% ± 5.6%. No correlation was found between the 2D and 3D HSI. The interobserver and intraobserver reliability was excellent.The 2D HSI seems to underestimate the humeral subluxation compared with a 3D reliable equivalent.

Anatomical shoulder arthroplasty is a reliable method used to alleviate pain and improve function in patients with glenohumeral arthritis. Recent research has focused on the handling of the subscapularis during anatomical shoulder arthroplasty. Four different approaches have been described: subscapularis tenotomy, subscapularis tendon peel, lesser tuberosity osteotomy, or a subscapularis preserving technique. In the literature, lesser tuberosity osteotomy shows better biomechanical and clinical results compared with subscapularis tenotomy. Two surgical techniques for lesser tuberosity osteotomy have been described: in line with the subscapularis tendon or perpendicular to the tendon. Both techniques show a high union rate and good clinical results but currently no biomechanical, radiological (muscular fatty degeneration), or randomized controlled clinical testing has been performed to evaluate significant differences. Subscapularis preserving techniques show good clinical results but are technically very demanding.

Background Shoulder range of motion (ROM) and strength measurements are imperative in the clinical assessment of the patient's status and progression over time. The method and type of assessment varies among clinicians and institutions. No comprehensive study to date has examined the reliability of a variety of procedures based on different testing equipment and specific patient or shoulder position. The purpose of this study was to establish absolute and relative reliability for several procedures measuring the rotational shoulder ROM and strength into internal (IR) and external (ER) rotation strength. Methods Thirty healthy individuals (15 male, 15 female), with a mean age of 22.1 ± 1.4 years, were examined by 2 examiners who measured ROM with a goniometer and inclinometer and isometric strength with a hand-held dynamometer (HHD) in different patient and shoulder positions. Relative reliability was determined by intraclass correlation coefficients (ICC). Absolute reliability was quantified by standard error of measurement (SEM) and minimal detectable change (MDC). Systematic differences across trials or between testers, as well as differences among similar measurements under different testing circumstances, were analyzed with dependent t tests or repeated-measures analysis of variance in case of 2 or more than 2 conditions, respectively. Results Reliability was good to excellent for IR and ER ROM and isometric strength measurements, regardless of patient or shoulder position or equipment used (ICC, 0.85-0.99). For some of the measurements, systematic differences were found across trials or between testers. The patient's position and the equipment used resulted in different outcome measures. Conclusions All procedures examined showed acceptable reliability for clinical use. However, patient position and equipment might influence the results.

Background Type B glenoids according to Walch are subclassified into a group with no posterior erosion (B1) and a group with important posterior erosion (B2) based on 2-dimensional axial computed tomography (CT) scan images. Three-dimensional (3D) CT scan reconstruction seems to improve the accuracy of the measurement of erosion because of its independence from positional errors. The aim is to quantify the direction and amount of posterior erosion of type B glenoids using a reproducible 3D measuring technique. Methods We performed 3D reconstruction of 72 type B glenoids (24 type B1 glenoids and 48 type B2 glenoids) using Mimics (Materialise, Haasrode, Belgium). The native glenoid plane and intermediate glenoid plane were determined by use of 3-Matic (Materialise). The normal glenoid version, eroded retroversion, and difference in retroversion were measured. Next, the maximum erosion and its orientation were quantified. Results There was always minimum erosion of 1.7 mm, and the mean erosion was 4.2 mm. There was a significant difference between the mean erosion in type B1 glenoids (3.5 mm) and type B2 glenoids (4.5 mm) ( P = .019). The mean orientation of the erosion was mostly to the posteroinferior side (119°; SD, 26.8). There was a significant difference between the mean orientation in type B1 glenoids (132°; SD, 25.2) and type B2 glenoids (113°; SD, 25.5) ( P = .004). Conclusions With the use of this newly developed reproducible measuring technique, the maximum erosion in type B glenoids can be adequately quantified. All glenoids showed signs of important erosion. Because the orientation of the maximum erosion in type B1 glenoids is situated more inferiorly, the 2-dimensional CT scan technique can be insufficient to evaluate this erosion.

As the number of reversed shoulder arthroplasty (RSA) procedures increases, the revision rate will also increase. In case of severe bone insufficiency, instability or infection of the primary RSA, revision to another RSA is preferable but not always possible. Hemiarthroplasty (HA), spacers and resection arthroplasty (RA) have been described in this indication.Between 2004 and 2016, 20 shoulders in 19 patients were treated at Ghent University Hospital for failed revision of RSA. Nine received a megahead prosthesis, a spacer was implanted in 6, and 5 underwent RA.Indications for implantation of a megahead prosthesis were loosening RSA (Our study shows that a megahead prosthesis has better functional results than RA, but is inferior to RSA. Due to increasing surgical experience and improving technique, 9 patients could ultimately be reconverted to another RSA. A review of current literature is presented. In HA and RA, the functional results are poor, and pain relief is uncertain. Results of spacers are variable and can be satisfactory. Arthrodesis is a last resort.In our case series study, a hemiarthroplasty can be performed in case of failure of RSA. However, the results are inferior to another RSA.Da die Zahl der inversen Schulterprothesen („reversed shoulder arthroplasty“, RSA) steigt, nimmt auch die Revisionsrate zu. Im Fall einer schweren ossären Insuffizienz, Instabilität oder Infektion der primären RSA ist eine Revision mit Erneuerung der RSA wünschenswert, aber nicht immer möglich. Hemiprothesen (HA), Spacer und Resektionsprothesen (RA) wurden für diese Indikation beschrieben.Zwischen 2004 und 2016 wurden 20 Schultern von 19 Patienten im Ghent University Hospital wegen einer fehlgeschlagenen RSA-Revision behandelt. Neun Patienten erhielten eine Großkopfprothese, bei 6 Patienten wurde ein Spacer implantiert und 5 erhielten eine RA.Indikationen für die Implantation einer Großkopfprothese waren eine gelockerte RSA (Unsere Studie zeigt, dass eine Großkopfprothese bessere funktionelle Ergebnisse zeigt als eine RA, sie einer RSA jedoch unterlegen ist. Aufgrund zunehmender chirurgischer Erfahrung und verbesserter Technik konnten 9 Patienten schließlich einer erneuten RSA-Operation zugeführt werden. Ein Review der aktuellen Literatur wird vorgestellt. Bei HA und RA sind die funktionellen Ergebnisse schlecht, und die Verbesserung der Schmerzsymptomatik ist ungewiss. Die Ergebnisse der Spacer fallen unterschiedlich aus und können als zufriedenstellend bezeichnet werden. Die Arthrodese ist das Ultima ratio.Die vorliegende Fallstudie zeigt, dass im Fall eines RSA-Versagens eine Hemiprothese implantiert werden kann. Jedoch sind die Ergebnisse im Vergleich zu einer neuen RSA unterlegen.

Osteotomy of the lesser tuberosity in shoulder arthroplasty allows bony healing of the subscapularis tendon but does not prevent fatty degeneration in its muscle. Occurrence or increase in fatty degeneration may depend on the surgical technique.We (1) assessed fatty degeneration in the subscapularis muscle and its cross-sectional area after a C-block osteotomy of the lesser tuberosity with minimal mobilization of the subscapularis muscle, and (2) determined whether this technique had any adverse effect on function, fatty degeneration, and cross-sectional area of the subscapularis muscle.We retrospectively examined 36 patients with shoulder replacements who had C-block osteotomies. Constant-Murley scores and clinical signs of subscapularis insufficiency were recorded. We radiographically assessed prosthetic placement. On CT scans, lesser tuberosity healing, fatty degeneration, and cross-sectional area of the subscapularis muscle were determined. The minimum followup was 13 months (mean, 18 months; range, 13-33 months).The mean absolute Constant-Murley score was 71.2. Two patients had weakness of the subscapularis muscle without loss of active motion. All tuberosities healed anatomically. A normal glenohumeral relationship was found in all cases. Fatty degeneration was Grade 0 in 44%, Grade 1 in 39%, Grade 2 in 14%, and Grade 3 in 3%. The subscapularis muscular cross-sectional area decreased from 16.7 cm(2) preoperatively to 14.5 cm(2) postoperatively (13%).The C-block osteotomy with minimal dissection of the subscapularis is associated with a low incidence of fatty degeneration in the subscapularis muscle after shoulder arthroplasty although the muscular cross-sectional area of the subscapularis decreased.Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Posterior shoulder instability has been difficult to diagnose and even more challenging to manage. However, it is being diagnosed and treated more frequently, particularly after sports injuries. The purpose of this article is to review literature concerning the management of these pathologies. A literature review was carried out in the main medical databases to evaluate the several studies concerning the open and arthroscopic treatment of posterior shoulder instability. Because of better awareness of the pathology, better technical investigations, and a better understanding of shoulder biomechanics, more and more mechanical factors that can cause posterior instability have been described. Structural abnormalities can be divided into bony abnormalities and soft-tissue abnormalities. Each group can also be divided into abnormalities caused by trauma (macro- or microtrauma) or congenital. These abnormalities can be treated with non-anatomic and anatomic stability procedures. During the last decades, the latter have been described more frequently, most of them arthroscopically. For surgical treatment to be successful, the instability must be attributable to mechanical factors that can be modified by surgery. Because of better knowledge of the pathology, a more specific surgery can be performed. This lesion-specific surgery has improved clinical results compared to non-anatomic stability procedures, particularly when that surgery has been performed arthroscopically.

The Delta XTEND design is an improvement of the original Delta CTA design. All the principals of Professor Grammont, which are proven to be clinical effective by many medical centers with a follow-up of more than 15 years, are included. The DELTA XTEND has been designed to improve the range of motion and to reduce the scapular notching by creating an inferior glenosphere overlap, with the center of rotation still located at the glenoid plane, thereby eliminating any rocking horse effects. Additionally, despite the fact that the metaglene is substantially smaller, the stability has been improved by adding a curved back glenoid with variable angle, locking, and compression screws. The introduction of a two-piece stem design allows for version adjustment and an offset epiphyseal component so that more anterior cortical bone can be preserved. The polyethylene cups are offered in multiple thicknesses with a standard, high mobility, or retentive option allowing the surgeon to achieve the optimal joint stability for each patient. It is also possible to mix the any size humeral cup diameter with any size glenosphere. At last but not at least the surgical technique to implant this reverse prosthesis is simple and made more easier because of the smaller (2/3 of a circle) reamers and the reduced volume of the glenosphere (less than have a sphere).

The humerus is primarily affected in approximately 10 % of patients by primary bone tumors. Furthermore, the proximal humerus is a preferred location of metastatic invasion for breast carcinoma and renal cell carcinoma. Limb salvage surgery is indicated for these patients if a functional limb remains after tumor resection and if the patient’s general condition permits surgery. For the shoulder, the majority of resections involve a type I or V according to Malawer’s classification. Restoration of shoulder function after proximal humeral resection for oncological reasons is still a challenge. In most oncological cases, resection of the rotator cuff is necessary to obtain eradication of the tumor. For these patients, reverse shoulder arthroplasty can provide durable midterm function. The location of the tumor determines whether a reversed arthroplasty in combination with a transfer of the latissimus dorsi and teres major muscle can be used to overcome the problem of insufficient external rotation strength after rotator cuff resection.

UNLABELLED An alternative treatment for primary bone tumors of the proximal humerus was assessed. Four patients, who made full functional recovery after complete resection of the proximal humerus inclusive of the rotator cuff and subsequent reconstruction with a reverse shoulder prosthesis, were examined clinically and radiographically. Distinct medialization of the center of rotation of the glenohumeral joint (28 mm) and elongation of the remaining deltoid muscle (116%) were measured. Increased scapular rotation (118%) was observed. The radiologic results and thoracoscapular rhythm analyses were implemented in a three-dimensional computerized model of the glenohumeral joint. This allowed us to calculate a doubling of the moment of the deltoid abductor muscle in the true scapular plane. After tumor surgery, in which the proximal humerus is resected without reinserting the rotator cuff, full functional recovery of the shoulder can be obtained with a total shoulder prosthesis, medializing the glenohumeral center of rotation and elongating the remaining deltoid muscle. LEVEL OF EVIDENCE Therapeutic study, Level IV (case series-no, or historical control group).

Reconstruction of a normal glenohumeral relationship is desirable for a successful arthroplasty. Double-contrast computed tomography was performed on 49 healthy shoulders in young volunteers. For creation of a uniform spatial reference system, the subjects were positioned in a thoracobrachial orthosis with the arm adducted in the coronal plane and the forearm flexed in the sagittal plane, and they were examined in dorsal recumbency. The classical anatomic angles were measured, and the anatomic axes were determined and quantified as angles to the coronal plane. When the axis of the glenoid was correlated to the axis of the humeral head, a mean of 8.5 degrees divergence in a clear Gaussian distribution was found. This contrasts with the variability of the version of the humeral head and of the glenoid and offers a useful guideline in difficult prosthetic surgery of the shoulder in which normal anatomic landmarks are lost because of arthritic or traumatic deformity.

The knowledge of shoulder pathology has improved tremendously in the last decades, and shoulder surgery is increasingly performed because of new treatment options and better operative results. Nowadays most surgical shoulder procedures are performed in the sitting or semi-sitting (beach chair) position. Stability of the patient and the ability to flex, extend and rotate the shoulder during surgery are crucial to improve exposure of the surgical field and lower the risk of perioperative complications. We developed an easy, safe and inexpensive surgical set-up providing a very good posterior, superior and anterior access to the shoulder in the sitting or semi-sitting position. In this technique, the patient is placed supine with the head at the foot end of the table and the body positioned slightly eccentrically with the back being supported by the leg plate contralateral to the operative side, avoiding any contact with the scapula of the operative side. A neck support is attached on an extra bar at the contralateral side and accommodated to the patient's lordosis. Next, the leg plate on the operative side is removed, and the head and the body are secured to the table with adhesive dressing. This way a stable positioning of the patient is obtained during the whole procedure, and the shoulder girdle is completely free. The set-up can accommodate patients of different stature and weight without the need to adapt the technique. This position also gives the possibility to provide an excellent radiographic view of the shoulder during operative fracture treatment. Our technique further allows a significant reduction in costs. A surgical table, extra bar, additional arm support and neck support are usually available and can be used in different settings, without the need for a specific shoulder table.

Background Patients with cleidocranial dysplasia (CCD) can have a congenital partial or total absence of the clavicle. The aim of this study was to evaluate the functional shoulder score in these patients. Material and methods Patients with CCD who were members of a social media group were invited to take part in an Internet-based survey. The questionnaire was composed of 3 general questions, a question concerning partial or total absence of the clavicle, and 3 patient-based shoulder scores (American Shoulder and Elbow Surgeons score; shortened Disabilities of the Arm, Shoulder, and Hand score; and patient-based Constant-Murley score). Results Thirty-six patients (27 women, 9 men) with a mean age of 40 years participated in the survey; 17 patients had a bilateral absence, 16 patients had a bilateral partial absence, and 3 patients had a total absence on one side and a partial absence of the clavicle on the other side. The average patient-based Constant-Murley score was 79; shortened Disabilities of the Arm, Shoulder, and Hand score, 11; and American Shoulder and Elbow Surgeons score, 93. There was no significant difference in the scores between left and right. There was no correlation between partial and total absences and the shoulder scores. Conclusion Patients with self-reported CCD are subjectively normal to their peers when they are evaluated with 3 common shoulder scores. There was no correlation between partial and total absences and the shoulder scores.

Introduction Recently, arthroscopy of the sternoclavicular joint (SCJ) has been described in clinical setting. The aim of this study is to examine the accessibility and safety of the SCJ by arthroscopy in a cadaveric model. Materials and methods An inferolateral and superomedial portal to the SCJ was created in 20 cadaveric specimens. After debridement, the specimens were dissected with a needle positioned in the portal tracts. The distance between the needles and bony landmarks, tendons and ligaments were measured. The integrity of the posterior capsule was evaluated macroscopically. In eight specimens, after anterior dissection, the needles were replaced by K-wires that perforated the posterior capsule to evaluate the distance to the neurovascular structures behind the SCJ. Results Both portals were found to be safe while allowing good access to the joint. The superomedial portal went through the tendon of the sternocleidomastoideus muscle and the inferolateral portal through the pectoralis major muscle. The portals entered the capsule medial and lateral to the anterior sternoclavicular ligament. The posterior capsule was never perforated during debridement. The perforating K-wires, however, usually perforated either a major vein or artery, but were at a safe distance from the vagal nerve. Conclusions In this cadaver study, arthroscopy of the sternoclavicular joint could be used as a minimally invasive procedure allowing debridement of the joint without damaging the posterior capsule of the joint. If the capsule is inadvertently be breached, a major risk of neurovascular damage exists. We advise to have a backup of a cardiothoracic surgeon when performing this procedure.

Background Correct reaming of a degenerative glenoid can be a difficult procedure. We investigated how the quality of the reamed surface is influenced by different reamers, by the surgeon's experience, and by glenoid erosion patterns. Material and methods Three shoulder surgeons performed reaming procedures with different types of reamers (flat, convex, K-wire guided, and nipple guided) on a series of similarly sized uniconcave and biconcave glenoids. The reproducibility of reaming and the effect of different reamers on different-shaped glenoids were measured and evaluated. Results The center and direction of reaming were constant for all surgeons in the case of type A glenoids. For type B2 glenoids, the center and direction of reaming differed significantly between surgeons. The congruity of the reamed surface was better after flat reaming than after convex reaming. Whether the reamers were guided by a central K-wire or by a nipple had no significant effect on the reamed surface. The experience of the surgeon had no effect on the congruity of reaming. Conclusions Reaming of a uniconcave glenoid is reproducible, but reaming of a biconcave glenoid seems much more difficult. Erosion and deformity of the glenoid influence the accuracy of reaming the most. Surgical experience plays a less important role. We conclude that there is a need for guidance in reaming of biconcave glenoids.

Background Symptomatic atrophic nonunion after multiple clavicle osteosynthesis can be difficult to treat. The aim of this study was to evaluate the results of a transfer of the clavicular part of the pectoralis major muscle as augmentation of osteosynthesis of these nonunions. Materials and methods A retrospective study included all patients who were treated between 2001 and 2010 (minimum 2-year follow-up). The indications for primary surgery, the number of operations, and the indication for a pectoralis major transfer were evaluated. Time of radiologic consolidation and postoperative complications were assessed. Clinical evaluation was performed with preoperative and postoperative satisfaction ratings and Constant-Murley scores. Results The study included 11 patients. The indications for a primary osteosynthesis were acute displaced fractures (7), delayed union (2), nonunion (1), and malunion (1). On average, 3.7 procedures were performed (range, 2-6) before the tendon transfer. At revision, there were 2 patients with infection and 9 without infection. Of the 11 clavicles, 10 showed radiologic consolidation after a mean time of 10 weeks (6-20 weeks). The mean follow-up was 62 months (24-132 months). The mean Constant-Murley score increased from 37 (24-55) preoperatively to 59 (43-98), and the satisfaction rating increased from 2 (1-3) to 7 (2-10). Complications included nonunion (1), hardware removal (2), hardware irritation (4), and donor site pain (1). Conclusion The use of the clavicular part of the pectoralis major transfer as an augmentation in revision for symptomatic atrophic nonunion after multiple clavicle osteosynthesis showed good radiologic and acceptable clinical results.

Background Loosening of the glenoid component remains the most common problem in total shoulder arthroplasty. It has been described that the round-backed, all-polyethylene components with cemented peg fixation perform better biomechanically and clinically than flat-backed, metal-backed, or keeled components. However, side effects of cementing have been described. We hypothesized that cementing of a specific type of all-polyethylene glenoid component with 3 peripheral pegs and 1 central anchor peg is not necessary to obtain good clinical and radiologic results. Materials and methods Thirty-four shoulders (34 patients), with a mean follow-up of 28.3 months, were evaluated clinically with the Constant-Murley score and the SF-12 Health Survey score. The fixation of the glenoid component was evaluated with computed tomography scan. Results The Constant-Murley score increased from 40.2 points (range, 13-73 points) preoperatively to 72 points (range, 54-93 points) postoperatively. The SF-12 Physical Component Summary score was 45, and the SF-12 Mental Component Summary score was 50. No signs of loosening were seen around the pegs or glenoid in 30 shoulders. Signs of loosening were seen around the central anchor peg and the peripheral pegs in 4 shoulders. There was no statistical difference between the clinical outcome of patients with and without signs of loosening. Conclusion The clinical and radiologic evaluation of an uncemented all-polyethylene glenoid is promising, with good clinical results and with no signs of loosening in 88% of the patients on computed tomography scans.

Purpose To investigate superior value of adding heavy load eccentric training to conservative treatment in patients with subacromial impingement. Methods Sixty-one patients with subacromial impingement were included and randomly allocated to the traditional rotator cuff training (TT) group (n = 30, mean age = 39.4 ± 13.1 years) or traditional rotator training combined with heavy load eccentric training (TT ? ET) group (n = 31, mean age = 40.2 ± 12.9 years). Isometric strength was measured to abduction at 0 ,4 5 and 90 of scapular abduction and to internal and external rotation. The SPADI questionnaire was used to measure shoulder pain and function. Patients rated subjective perception of improvement. Outcome was assessed at baseline, at 6 and 12 weeks after start of the intervention. Both groups received 9 physiotherapy treatments over 12 weeks. At home, the TT group performed traditional rotator cuff strengthening exercises 1x/day. The TT ? ET group performed the same exercises 1x/day and a heavy load eccentric exercise 2x/day. Results After treatment, isometric strength had significantly increased in all directions, and SPADI score had significantly decreased. The TT ? ET group showed a 15 % higher gain in abduction strength at 90 of scapular abduction. Chi-square tests showed patients’ self-rated perception of improvement was similar in both groups. Conclusion Adding heavy load eccentric training resulted in a higher gain in isometric strength at 90 of scapular abduction, but was not superior for decreasing pain and improving shoulder function. This study showed that the combination of a limited amount of physiotherapy sessions combined with a daily home exercise programme is highly effective in patients with impingement. Level of evidence II.

The use of reverse shoulder arthroplasty has considerably increased since first introduced in 1985. Despite demonstrating early improvement of function and pain, there is limited information regarding the durability and longer-term outcomes of this prosthesis.We determined complication rates, functional scores over time, survivorship, and whether radiographs would develop signs of loosening.We retrospectively reviewed 527 reverse shoulder arthroplasties performed in 506 patients between 1985 and 2003. Clinical and radiographic assessment was performed in 464 patients with a minimum followup of 2 years and 148 patients with a minimum followup of 5 years (mean, 7.5 years; range, 5-17 years). Cumulative survival curves were established with end points being prosthesis revision and Constant-Murley score of less than 30 points.Eighty-nine of 489 had at least one complication for a total of 107 complications. Survivorship free of revision was 89% at 10 years with a marked break occurring at 2 and 9 years. Survivorship to a Constant-Murley score of less than 30 was 72% at 10 years with a marked break observed at 8 years. We observed progressive radiographic changes after 5 years and an increasing frequency of large notches with long-term followup.Although the need for revision of reverse shoulder arthroplasty was relatively low at 10 years, Constant-Murley score and radiographic changes deteriorated with time. These findings are concerning regarding the longevity of the reverse shoulder arthroplasty, and therefore caution must be exercised when recommending reverse shoulder arthroplasty, especially in younger patients.Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Background The impact of rotator cuff tendinopathy and related impingement on proprioception is not well understood. Numerous quantitative and qualitative changes in shoulder muscles have been shown in patients with rotator cuff tendinopathy. These findings suggest that control of force might be affected. This investigation wants to evaluate force sensation, a submodality of proprioception, in patients with rotator cuff tendinopathy. Methods Thirty-six patients with rotator cuff tendinopathy and 30 matched healthy subjects performed force reproduction tests to isometric external and internal rotation to investigate how accurately they could reproduce a fixed target (50% MVC). Relative error, constant error, and force steadiness were calculated to evaluate respectively magnitude of error made during the test, direction of this error (overshoot or undershoot), and fluctuations of produced forces. Results Patients significantly overshoot the target (mean, 6.04% of target) while healthy subjects underestimate the target (mean, −5.76% of target). Relative error and force steadiness are similar in patients with rotator cuff tendinopathy and healthy subjects. Force reproduction tests, as executed in this study, were found to be highly reliable (ICC 0.849 and 0.909). Errors were significantly larger during external rotation tests, compared to internal rotation. Conclusion Patients overestimate the target during force reproduction tests. This should be taken into account in the rehabilitation of patients with rotator cuff tendinopathy; however, precision of force sensation and steadiness of force exertion remains unaltered. This might indicate that control of muscle force is preserved.

Normal function of the upper limb is seldom restored after limb-sparing surgery for tumors of the proximal humerus. The literature suggests superior shoulder function is achieved in the short term with reverse total shoulder arthroplasty compared to other techniques when performed for conditions with rotator cuff deficiency. It is unclear whether this superiority is maintained when reverse total shoulder arthroplasty is performed for tumors.When performed for tumors, we determined whether reverse total shoulder arthroplasty restores function and improves motion, the complications associated with the surgery, and whether reverse total shoulder arthroplasty with autologous grafting is associated with bone resorption.We retrospectively reviewed 14 patients who had undergone reverse total shoulder arthroplasty for tumors of the proximal humerus. Four patients died, leaving nine patients for review. The surviving patients were evaluated clinically and radiographically. The minimum followup was 0.6 years (mean, 7.7 years; range, 0.6-12 years).At last followup, mean active abduction was 157° and mean functional Constant-Murley score was 76%. One patient had a deep infection and one developed a loose prosthesis; both were treated with single-stage exchange. At last followup, both patients had reasonable function without evidence of infection or loosening. Radiographic graft resorption was seen in all but one patient.Our observations suggest, at medium-term followup, reverse total shoulder arthroplasty is a reasonable option for tumors of the proximal humerus. It has low morbidity, restores a mean active abduction of 157°, and limits the impairment of activities of daily living.Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Background This study evaluates the preoperative conventional anteroposterior radiography and clinical testing in non-operated patients with cuff tear arthropathy. It analyses the radiological findings in relation to the status of the rotator cuff and clinical status as also the clinical testing in relation to the rotator cuff quality. The aim of the study is to define the usefulness of radiography and clinical examination in cuff tear arthropathy. Methods This study analyses the preoperative radiological (AP-view, (Artro-)CT-scan or MRI-scan) and clinical characteristics (Constant-Murley-score plus active and passive mobility testing) and the peroperative findings in a cohort of 307 patients. These patients were part of a multicenter, retrospective, consecutive study of the French Orthopaedic Society (SOFCOT-2006). All patients had no surgical antecedents and were all treated with prosthetic shoulder surgery for a painful irreparable cuff tear arthropathy (reverse-(84%) or hemi-(8%) or double cup-bipolar prosthesis (8%)). Results A positive significancy could be found for the relationship between clinical testing and the rotator cuff quality; between acromiohumeral distance and posterior rotator cuff quality; between femoralization and posterior rotator cuff quality. Conclusion A conventional antero-posterior radiograph can not provide any predictive information on the clinical status of the patient. The subscapular muscle can be well tested by the press belly test and the teres minor muscle can be well tested by the hornblower' sign and by the exorotation lag signs. The upward migration index and the presence of femoralization are good indicators for the evaluation of the posterior rotator cuff. An inferior coracoid tip positioning suggests rotator cuff disease.

Combined pectoralis major disruption and proximal humeral fractures are uncommon. A simple radiologic diagnostic tool which consists of the measurement of the displacement from the humeral shaft to the lateral side of the humeral head (lateral to the outer proximal cortex) can help to diagnose this combined lesion.

Reversed total shoulder arthroplasty is becoming more and more popular, especially in Europe and, recently, in the United States. 9 This treatment is currently considered to give superior functional results compared with other types of treatment for patients with severe cuff tear arthropathy, 1,8,10 patients with rheumatoid arthritis and irreparable rotator cuff lesions, 11,13 patients with tumors of the proximal humerus, 2,3 and patients undergoing revision arthroplasty. 4 Reversed shoulder arthroplasty can restore shoulder function in the absence of a rotator cuff 12 ; apparently, no (intact) osseous proximal humerus is required. The only contraindications appear to be a nonfunctional deltoid muscle, insufficient glenoid bone stock, and active infection. Despite the promising results in patients who were, until now, considered to be functionally untreatable, we have already been confronted with some humeral implant failures. We present 3 different types of humeral implant failure of the reversed total shoulder prosthesis, although it is generally accepted that the major source of mechanical failure of this constrained shoulder prosthesis will be at the glenoid site. 9,12

We modified the Hawkins impingement maneuver in order to develop a quantifiable and reproducible impingement test. The involved anatomic structures were examined with magnetic resonance imaging of 3 cadaveric shoulders. The reproducibility of the clinical sign was assessed with an interobserver and intraobserver reliability test, with calculation of the intraclass correlation coefficient (ICC). The quantified Hawkins maneuver appears to be a reproducible clinical test (median interobserver ICC, 0.9331; median intraobserver ICC, 0.9748) and creates bony contact between the greater tuberosity and the anterolateral acromion. This test enables the clinician to quantify the subacromial space.

Purpose: Successful total shoulder arthroplasty (TSA) requires a correct position of the glenoid component. This study compares the accuracy of the positioning with a new developed glenoid aiming device and virtual three-dimensional computed tomography (3D-CT) scan positioning. Materials and Methods: On 39 scapulas from cadavers, a K-wire (KDev) was positioned using the glenoid aiming device. It consists of glenoid components connected to the aiming device, which cover 150 degrees of the inferior glenoid circle, has a fixed version and inclination and is available with several different radii. The aiming device is stabilized at the most medial scapular point. The K-wire is drilled from the center of the glenoid component to this most medial point. All scapulas were also scanned with CT and 3D reconstructed. A virtual K-wire (Kct) was positioned in the center of the glenoid and in the scapular plane. Several parameters were compared. Radius of the chosen glenoid component (rDev) and the virtual radius of the glenoid circle (rCT), spinal scapular length with the device (SSLdev) and virtual (SSLct), version and inclination between KDev and Kct, difference between entry point and exit point ("Matsen"-point). Results: Mean rDev: 14 mm +/- 1.7 mm and mean rCT: 13.5 mm +/- 1.6 mm. There was no significant difference between SSLdev (110.6 mm +/- 7.5 mm) and SSLct (108 mm +/- 7.5 mm). The version of KDev and Kct was -2.53 degrees and -2.17 degrees and the inclination 111.29 degrees and 111.66 degrees, respectively. The distance between the "Matsen-point" device and CT was 1.8 mm. Conclusion: This glenoid aiming device can position the K-wire on the glenoid with great accuracy and can, therefore, be helpful to position the glenoid component in TSA. The level of evidence: II.

To the editor We congratulate Boileau et al. on their article, “Bony Increased-offset Reversed Shoulder Arthoplasty” [1], and their innovative idea of using an autograft to avoid the reduced motion and notching associated with humeral medialization. Their results are encouraging. However, we have some comments regarding parts of the Methods and Discussion sections. In the Methods section, they state that a 36-mm-diameter glenosphere usually was used for women, whereas the 42 mm was preferred for men. The disc of cancellous bone graft thickness was adjusted according to the size of the sphere. They stated that the reason why the thickness of the bone graft was adjusted according to the size of the sphere was because a 42-mm sphere already is more lateralized than the 36-mm sphere. It is unclear what they mean when they say it is already more lateralized. If they mean the center of rotation, then this is not correct. The center of rotation does not change by enlarging the diameter of the glenosphere. Unlike with a normal shoulder of an anatomic prosthesis, with a reverse prosthesis the humerus is not spinning around the center of rotation but is hinging around the center of rotation. Therefore by changing the diameter of the glenosphere, one does not change the center of rotation, but lateralize the hinging humerus [3]. If they mean that the humeral stem is lateralized more in the 42-mm glenosphere this is correct and it means that the humerus is lateralized in the same extent in both options (10-mm graft with 36-mm glenosphere [radius 18 mm] = 28 mm = 7-mm graft with 42-mm glenophere [radius 21 mm]). In the Discussion section, Boileau et al. stated inferior scapular notching occurred in 19%. This is lower than that reported with a standard medialized RSA [4]. Boileau et al. did not describe if there was a difference between the prevalence of scapular notching between the group with a 36-mm glenosphere and the group with a 42-mm glenosphere. This would be interesting to know because using a larger hemisphere on the same position of the baseplate means that there is more prosthetic overhang. Using a computer model we found that prosthetic overhang should reduce inferior impingement and presumably notching [2]. We believe that using a cancellous bone graft of 29 mm in diameter (identical to the radius of the baseplate) with either a 36-mm or a 42-mm glenopsphere is likely to decrease the risk of inferior impingement similarly (36-mm glenosphere [18 mm radius] and 29-mm diameter bone graft [14.5 mm radius] = 4.5-mm prosthetic overhang, 42-mm glenosphere [21 mm radius] and 29-mm diameter bone graft [14.5 mm radius] = 7.5-mm prosthetic overhang). We believe that prosthetic overhang caused by a larger sphere and a smaller bone graft can contribute to the lower rate of scapular notching reported by Boileau et al.