Osteoarthritis (OA) is a disease of the synovial joint with synovial inflammation, capsular contracture, articular cartilage degradation, subchondral sclerosis and osteophyte formation contributing to pain and disability. Transcriptomic datasets have identified genetic loci in hip and knee OA demonstrating joint specificity. A limited number of studies have directly investigated transcriptional changes in shoulder OA. Further, gene expression patterns of periarticular tissues in OA have not been thoroughly investigated. This prospective case control series details transcriptomic expression of shoulder OA by analysing periarticular tissues in patients undergoing shoulder replacement for OA as correlated with a validated patient reported outcome measure of shoulder function, an increasing (clinically worsening) QuickDASH score. We then compared transcriptomic expression profiles in capsular tissue biopsies from the OA group (N=6) as compared to patients undergoing shoulder stabilisation for recurrent instability (the control group, N=26). Results indicated that top ranked genes associated with increasing QuickDASH score across all tissues involved inflammation and response to stress, namely interleukins, chemokines, complement components, nuclear response factors and immediate early response genes. Some of these genes were upregulated, and some downregulated, suggestive of a state of flux between inflammatory and anti-inflammatory signalling pathways. We have also described gene expression pathways in shoulder OA not previously identified in hip and knee OA, as well as novel genes involved in shoulder OA.

Purpose. There is minimal information on outcome of glenohumeral debridement for treatment of shoulder osteoarthritis (OA). The purpose of this study was to examine the outcome of this procedure with or without acromioplasty /resection of clavicle in subjective perception of disability and functional range of motion and strength at one year following surgery. Method. Prospectively collected data of patients with advanced OA of the glenohumeral joint who were not good candidates for shoulder arthroplasty due to young age, high activity level, or desire to avoid major surgery at the time of assessment were included. Arthroscopic debridement included removal of loose bodies, chondral flaps, and degenerative tissue. Resection of the lateral end of the clavicle or acromioplasty was performed as clinically indicated for management of osteoarthritis of the Acromioclavicular (AC) joint or subacromial impingement respectively. Disability at 12 months following surgery was measured by the American Shoulder and Elbow Surgeons (ASES) assessment form, Constant-Murley score (CMS), strength, and painfree range of motion in four directions. Results. Sixty-seven patients (mean age= 57, SD: 15 (range: 25–87), range: 35–86, 35 females, 32 males) were included in analysis. The average symptom duration was 5 years. Fifteen (22%) patients had left shoulder involvement with 37 (55%) having right shoulder problem and 15(22%) reporting bilateral complaints. The right shoulder was operated on in 41 (61%) patients. Fifty two (78%) patients had an associated subacromial decompression [49 (73%) had acromioplasty and 27 (40%) had resection of the lateral end of the clavicle with some procedures overlapping]. Paired student t-tests showed a statistically significant improvement in scores of ASES and CMS (p<0.001) and painfree range of motion (p=0.02) at 1 year follow-up. However, no change was observed in strength (p>0.05). Conclusion. Arthroscopic debridement with or without acromioplasty /resection of the lateral end of the clavicle improves disability and painfree range of motion in patients suffering from osteoarthritis of glenohumeral joint at one year following surgery

Introduction:. Total shoulder arthroplasty (TSA) is the current standard treatment for severe osteoarthritis of the glenohumeral joint [1]. Often, severe arthritis is associated with abnormal glenoid version or excessive posterior wear [2]. Reaming to correct more than 15° of retroversion back to neutral is not ideal as it may remove an excessive amount of the outer cortical support and medialize the glenoid component [3]. Two recent glenoid components with posterior augments—wedged and stepped—have been designed to address excessive posterior wear and to allow glenoid component neutralization. Hypothetically, these augmented glenoid designs lessen the complications associated with using a standard glenoid component in cases of shoulder osteoarthritis with excessive posterior wear. We set out to determine which implant type (standard, stepped, or wedged) corrects retroversion while removing the least amount of bone in glenoids with posterior erosion. Methods:. Serial shoulder CT scans were obtained from 121 patients before total shoulder arthroplasty. These were then classified using the Walch Classification. We produced 3D models of the scapula from CT scans for 10 subjects that were classified as B2 using the software MIMICS (Materialise, Belgium). Each of these 10 glenoid subjects were then virtually implanted with standard, stepped, and wedged glenoid components (Fig 1). The volume of surgical bone removed and maximum reaming depth were calculated for each design and for each subject. In addition, the area of the backside of the glenoid in contact with cancellous versus cortical bone was calculated for each glenoid design and for each subject (Fig 2). ANOVA testing was performed. Results:. Arthritic bone loss in shoulder specimens was always posteroinferior, and the worn portion or neoglenoid made up an average of 68 ± 11% in the shoulder specimens. Mean surgical bone volume removed (2857 ± 1618 mm. 3. ) was least for the wedged component when compared to stepped (4307 ± 1485 mm. 3. , p=.0003) and conventional (5385 ± 2348 mm. 3. , p=.0003) designs. Maximum bone depth removed for the wedge (4.5 ± 2.3 mm) was less than the stepped (7.6 ± 1.4 mm, p=.00003) and conventional (9.7 ± 2.7 mm, p=.00001). The mean percentage of the implant's back surface supported by cancellous bone was 17.0% for the conventional, 6.1% for the stepped (p=.009), and 3.1% for the wedged (p=.0001). Discussion:. Both wedged and stepped components were able to correct glenoid version to neutral and required less bone removal, required less reaming depth, and were supported by more cortical bone than the standard implant. The wedged component was significantly better in these three categories than the stepped implant. There may be a mismatch between the usual patterns of wear that occurs in B2 glenoids where neoglenoid comprises (68 ± 11%) vs. the stepped implant's 50%. A stepped implant that matches the usual B2 glenoid may correct version while removing less bone than the current design

Background. Degeneration of the shoulder joint is a frequent problem. There are two main types of shoulder degeneration: Osteoarthritis and cuff tear arthropathy (CTA) which is characterized by a large rotator cuff tear and progressive articular damage. It is largely unknown why only some patients with large rotator cuff tears develop CTA. In this project, we investigated CT data from ‘healthy’ persons and patients with CTA with the help of 3D imaging technology and statistical shape models (SSM). We tried to define a native scapular anatomy that predesignate patients to develop CTA. Methods. Statistical shape modeling and reconstruction:. A collection of 110 CT images from patients without glenohumeral arthropathy or large cuff tears was segmented and meshed uniformly to construct a SSM. Point-to-point correspondence between the shapes in the dataset was obtained using non-rigid template registration. Principal component analysis was used to obtain the mean shape and shape variation of the scapula model. Bias towards the template shape was minimized by repeating the non-rigid template registration with the resulting mean shape of the first iteration. Eighty-six CT images from patients with different severities of CTA were analyzed by an experienced shoulder surgeon and classified. CT images were segmented and inspected for signs of glenoid erosion. Remaining healthy parts of the eroded scapulae were partitioned and used as input of the iterative reconstruction algorithm. During an iteration of this algorithm, 30 shape components of the shape model are optimized and the reconstructed shape is aligned with the healthy parts. The algorithm stops when convergence is reached. Measurements. Automatic 3D measurements were performed for both the healthy and reconstructed shapes, including glenoid version, inclination, offset and critical shoulder angle. These measurements were manually performed on the mean shape of the shape model by a surgeon, after which the point-to-point correspondence was used to transfer the measurements to each shape. Results. The critical shoulder angle was found to be significantly larger for the CTA scapulae compared to the references (P<0.01). When analyzing the classified scapulae significant differences were found for the version angle in the scapulae of group 4a/4b and the critical shoulder angle of group 3 when compared to the references (P<0.05). Conclusion. Patients with CTA have a larger critical shoulder angle compared with reference patients. Some significant differences are found between the scapulae from patients in different stages of CTA and healthy references, however the differences are smaller than the accuracy of the SSM reconstruction. Therefore, we are unable to conclude that there is a predisposing anatomy in terms of glenoid version, inclination or offset for CTA

PURPOSE. To validate the efficacy and accuracy of a novel patient specific guide (PSG) and instrumentation system that enables minimally invasive (MI) short stemmed total shoulder arthroplasty (TSA). MATERIALS AND METHODS. Using Amirthanayagam et al.'s (2017) MI posterior approach reduces incision size and eliminates subscapular transection; however, it precludes glenohumeral dislocation and the use of traditional PSGs and instruments. Therefore, we developed a PSG that guides trans-glenohumeral drilling which simultaneously creates a humeral guide tunnel/working channel and glenoid guide hole by locking the bones together in a pre-operatively planned pose and drilling using a c-shaped drill guide (Figure 1). To implant an Affinis Short TSA system (Mathys GmbH), novel MI instruments were developed (Figure 2) for: humeral head resection, glenoid reaming, glenoid peg hole drilling, impaction of cruciform shaped humeral bone compactors, and impaction of a short humeral stem and ceramic head. The full MI procedure and instrument system was evaluated in six cadaveric shoulders with osteoarthritis. Accuracy was assessed throughout the procedure: 1) PSG physical registration accuracy, 2) guide hole accuracy, 3) implant placement accuracy. These conditions were assessed using an Optotrak Certus tracking camera (NDI, Waterloo, CA) with comparisons made to the pre-operative plan using a registration process (Besl and McKay, 1992). RESULTS. 3D translational accuracy of PSG physical registration was: humeral PSG- 2.2 ± 1.1 mm and scapula PSG- 2.5 ± 0.7 mm. The humeral and scapular guide holes had angular accuracies of 6.4 ± 3.2° and 8.1 ± 5.1°, respectively; while the guide hole positional accuracies on the articular surfaces (which will control bone preparation translational accuracy) were 2.9 ± 1.2 mm and 2.8 ± 1.3 mm. Final implantation accuracy in translation was 2.9 ± 3.0 mm and 5.7–6.8 ± 2.2–4.0° across the implants’ three rotations for the humerus and in translation was 2.8 ± 1.5 mm and 2.3–4.3 ± 2.2–4.4° across the implants’ three rotations for the scapula (Figure 3). DISCUSSION. The overall implantation accuracy was similar to results of previously reported open, unassisted TSA (3.4 mm & 7–12°, Hendel et al., 2012, Nguyen et al., 2009). Analysis of the positional PSG registration accuracy very closely mirrors the final implantation accuracy (humerus:2.2 mm vs 2.9 mm, and scapula:2.2 mm vs 2.8mm), thus, this is likely the primary predictor of implantation accuracy. Furthermore, the greatest component of PSG registration error was mediolateral translation (i.e. along the guiding axis) and thus should not affect guide hole drilling accuracy. The drilled guide hole positional and angular error was low for the humerus (2.9 mm and 6.4°) but somewhat higher in rotation (8.1°) for the glenoid which may indicate a slight shift in the PSG prior to guide hole drilling due to the weight of the arm applied when the PSGs are locked together. In conclusion, this work has detailed the step-by-step surgical errors associated with the developed system and demonstrated that it achieves similar accuracy to open, unassisted TSA, while avoiding complications related to muscular transection and dislocation. Therefore, we believe this technique is worthy of clinical investigation

Introduction. Shoulder arthroplasty is used to treat several common pathologies of the shoulder, including osteoarthritis, post-traumatic arthritis, and avascular necrosis. In replacement of the humeral head, modular components allow for anatomical variations, including retroversion angle and head-neck angle. Surgical options include an anatomic cut or a guide-assisted cut at a fixed retroversion and head-neck angle, which can vary the dimensions of the cut humeral head (height, anteroposterior (AP), and superoinferior (SI) diameters) and lead to negative long term clinical results. This study measures the effect of guide-assisted osteotomies on humeral head dimensions compared to anatomic dimensions. Methods. Computed tomography (CT) scans from 20 cadaveric shoulder specimens (10 male, 10 female; 10 left) were converted to three-dimensional models using medical imaging software. An anatomic humeral head cut plane was placed at the anatomic head – neck junction of all shoulders by a fellowship trained shoulder surgeon. Cut planes were generated for each of the standard implant head-neck angles (125°, 130°, 135°, and 140°) and retroversion angles (20°, 30°, and 40°) in commercial cutting guides. Each cut plane was positioned to favour the anterior humeral head-neck junction while preserving the posterior cuff insertion. The humeral head height and diameter were measured in both the AP plane and the SI plane for the anatomic and guide-assisted osteotomy planes. Differences were compared using separate two-way repeated measures ANOVA for each dependent variable and deviations were shown using box plot and whisker diagrams. Results. Guide-assisted cuts tend to be smaller than the anatomic humeral head dimensions. Retroversion angle showed a significant effect on head height, AP, and SI diameters (p=0.002). The effect of head-neck angle was only significant for SI diameter (p<0.001). The largest dimensional deviation was observed at 20 degrees of retroversion and resulted in a 2.5mm decrease in humeral head height, averaged over the range of head-neck values. Conclusion. Where patient's natural anatomy falls outside the range of commercial cutting guides, resection according to the template may result in a deviation from the natural dimensions of the humeral head, which impacts the sizing of the implant head component. This has implications for both manufacturers to create a template that has a larger range of retroversion angles, as well as surgeons' choices in intra-operative planning

Background. Massive rotator cuff tears and consequent cuff-deficient arthritis (CTA) of the shoulder can cause severe shoulder dysfunction in the elderly. Reverse total shoulder arthroplasty (RTSA) has been widely used for treatment of CTA in all over the world since its introduction in the 90's. In Japan, however, we have just started to clinically use RTSA from April 2014. In addition, we have only one choice of the implants (Aequalis Reverse, Tornier) currently, and only one size of the base-plate of the glenoid component (29 mm in diameter) is available so far. Japanese, especially elderly people, have generally smaller figure than Caucasians. We are not sure whether the base-plate would fit for the smaller Japanese. The purpose of this study was to measure the size of the glenoids in Japanese using CT images and to examine that they would fit the 29 mm base-plate. Methods. The shoulders without osteoarthritis of the glenohumeral joint were eligible for the study. The subjects consisted of 30 shoulders including 10 elderly males, 10 elderly females, and 10 younger males, and the mean ages were 73 (range, 63–81), 74 (range, 65–89), and 32 (range, 27–36) years old, respectively. Mean heights and weights were 164 cm (range, 156–179) and 59 kg (range, 49–72), 154 cm (range, 151–161) and 57 kg (range, 48–65), and 173 cm (range, 162–179) and 72 kg (range, 61–100), respectively. CT images with a 0.3 mm slice pitch were used for the analysis. The images were loaded into a DICOM viewer (OsiriX), and a slice for simulated implantation of the base-plate was created using the multi-planar reconstruction (Figure 1), which had 10° of inferior tilt to the glenoid face. The width of the glenoid in the antero-posterior direction was measured at 14 mm above the inferior edge of the glenoid. Results. Mean widths for the elderly males, elderly females, and younger males were 27.7 mm (range, 24.8–28.9), 25.3 mm (range, 24.4–25.9), and 27.8 mm (range, 25.9–29.8), respectively. Discussion. The present study revealed that most of the younger and elderly males would fit the 29 mm base-plate. However, the glenoid width of all elderly females in this study was much smaller than the base-plate diameter. The base-plate with smaller diameter is indispensable for Japanese, and the pre-operative planning may be important for secure surgeries

INTRODUCTION. The aim of this retrospective study is to evaluate clinically and radiographically the effectiveness of implanting an eccentric glenosphere and if a correct glenosphere positioning would avoid the occurrence of notching. METHODS. since 2006 40 patients with shoulder eccentric osteoarthritis were treated with reverse shoulder arthroplasty with a 36 mm eccentric glenosphere. We have selected 25 patients, with a minimum follow up of 24 months. The patients were clinically evaluated with the Constant score and SST and with X-ray, MRI and/or CT before and after surgery. At the follow up we evaluated the presence or absence of notch, and we measured the PSNA (prosthesis-scapular neck angle), the DBSNG (distance between the scapular neck angle and glenosphere), the PGRD distance (peg glenoid distance). Stastistical analysis was performed with a paired t test. RESULTS. In every patient the range of motion was improved. The AP X-ray did not show inferior scapular notching. The mean DBSNG, was found to be 4.3 mm. The mean PSNA was 92 ° and the mean PGRD was 21.2. The Constant score improved from 30 to 74 points and the SST from 1.7 to 8.4 points. DISCUSSION and CONCLUSION. The scapular notching is shown as the most frequent complication in reverse shoulder replacement. In our study the results indicate that proper positioning of the glenosphere with the inferior part of the metal back that overlaps the lower glenoid rim without overhang and the implantation of an eccentric glenosfere, lowers the center of rotation of 4 mm and avoid contact between the humeral component and the scapular neck during the adduction. Thus, all the patients increased the total joint range of motion