Subscapularis repair and integrity after a primary total shoulder arthroplasty is critical for successful outcomes. One should be familiar with the 3 basic takedown and repair techniques commonly utilised. Subscapularis repair after reverse shoulder arthroplasty is not as critical and in some cases may be detrimental to return of external rotation strength and motion. Subscapularis tenotomy: The tendon is incised approximately 1 cm from the lesser tuberosity and an oblique incision is created from proximal lateral to distal medial stopping at the sentinel vessels. A combination of tendon-to-tendon figure of 8 sutures. Lesser tuberosity osteotomy: This approach is helpful not only in obtaining a bone-to-bone healing, but also in the exposure. Osteotomies range from a fleck of bone in patients with minimal deformity, to a C-shaped osteotomy including part of the head which facilitates exposure of the posterior glenoid. Despite an ability to document radiographic healing of the lesser tuberosity fragment, this technique does not prevent fatty infiltration of the subscapularis. Subscapularis Peel: This repair requires tendon healing to bone and probably incomplete, in most cases, reconstitution of a normal enthesis. External rotation can be gained by recessing the subscapularis insertion medially with the arm in external rotation. While bone-to-tendon sutures are the gold standard, augmentation of the sutures using a prosthesis as the anchor has led to the development of prostheses with multiple holes. Dual row repair of the tendon, however, may lead to medial rupture

Background. Long term success of any shoulder joint reconstruction procedure involving subscapularis attachment take down is dictated by the way one chooses to release and repair/reconstruct the subscapularis insertion. There are several methods that were reported in the literature without any preset guidelines which are easily reproducible. Methods. 5 specimens of fresh cadaver shoulder joints dissected and the subscapularis footprint insertion involving the tendon and muscle exposed. We intend to preserve subscapularis tendon footprint along with the lesser tuberosity by performing the footprint osteotomy fashioned step wise in the following manner. Results. It has two vertical components (sagittal and coronal plane osteotomies) and one horizontal component (distal osteotomy at musculo tendinous junction level). Figure 1: demonstrating the three step cuts in the dry bone of proximal humerus with three different ostetomes to mark the plain of osteotomies in the lesser tuberosity. Step-1: Medial wall ridge of the inter-tubercular sulcus serves as landmark for sagittal component. The depth of sagittal component is just 5 – 10mm and its length extending from articular margin proximally and distally up to musculo tendinous junction, measuring approximately 15–20mm. Step-2: Coronal plane osteotomy is in line with and parallel to undersurface of subscapularis tendon adjacent to the articular margin and connecting sagittal component and measured 10–15mm approximately. Figure 2: demonstrating the two cuts / osteotomies to mark the sagittal and coronal components of the subscapularis foot print osteotomy in the lesser tuberosity of a fresh cadaver. Step-3: The horizontal component (distal osteotomy at musculo tendinous junction level is 5–10 mm in width, connects the two vertical components, thus completing the footprint osteotomy. Discussion. Subscapularis reattachment plays a pivotal role in the shoulder joint reconstruction procedures especially total joint arthroplasty. Subscapularis take down either by tenotomy or by periosteal elevation from lesser tuberosity followed by repair carries a risk of retraction and poor healing and early failure. Footprint osteotomy as a thin sliver of cortical bone instead of these above described three steps with the attached tendon carries a risk of fragmentation of the bone sliver along with lack of rotation control on the repair. The necessity for doing such a three step osteotomy procedure which results in a wedge shaped bone tendon foot print construct, we believe is of paramount importance for a successful reconstruction. Figure 3: demonstrating the marking sutures passed into the bone tendon construct comprising of lesser tuberosity and subscapularis for effective foot print reconstruction in a fresh cadaver. Conclusions. This three step footprint osteotomy of the Subscapularis tendon offers a stable construct which is easy to reproduce with better healing potential. For figures, please contact authors directly

Aim. Two different techniques to release subscapularis during total shoulder replacement (TSR) have been described (tenotomy and osteotomy) with no consensus as to which is superior. In this study we review the clinical outcomes of a sequential series of patients in whom a TSR for primary osteoarthritis had been performed using either technique at our institution. Subscapularis function was tested using a new graded belly press test, a modification of the traditional belly press test which is described for the first time here. Methods. All patients who underwent surgery at our institution between January 2002 and January 2010 and met the eligibility criteria, were included for analysis. Subscapularis function was assessed post-operatively using a range of functional assessments including; a graded belly press test, lift off test, and an assessment of each patient's range of movement. Results. A total of 36 shoulders in 36 patients were included, ten underwent subscapularis tenotomy and 26 underwent osteotomy of the lesser tuberosity. Patients who had undergone osteotomy of the lesser tuberosity had a more favourable outcome overall. They demonstrated a significantly better grade (grade 1) of the belly press test compared with the tenotomy group (p=0.026) and a trend towards a better range of movement although no statistical significance was shown. All patients (osteotomy and tenotomy) with a grade 1 belly press test had a better clinical outcome with data demonstrating statistical significance. Conclusion. Our results indicate that in this single surgeon sequential series of patients who underwent osteotomy of the lesser tuberosity during TSR for OA had a better functional outcome than those who underwent subscapularis tenotomy. While our modification of the belly press test may require further validation we would suggest it may be a more useful indicator of subscapularis function in future studies

Subscapularis function following Total shoulder joint replacement has been a concern in recent literature. It has been postulated that lesser tuberosity osteotomy approach may have better Subscapularis function than transtendonous approach. To assess whether lesser tuberosity osteotomy vs. subscapularis tenotomy is better for post-operative function of subscapularis in total shoulder replacements done by a single surgeon in a District general hospital. 117 shoulder replacements performed by the senior author (TH) at Waikato district general hospital between years January 2002 to January 2010 were reviewed retrospectively. Revision replacement, inverse shoulder replacement & acute traumatic hemiarthroplasty were excluded. Patients with previous rotator cuff problems, previous surgery to subscapularis, rheumatoid arthritis and post-trauma sequelae were also excluded from the study. Inclusion criteria were normal subscapularis function and intact subscapularis on MRI pre-operatively. 41 shoulders were eligible to participate in study of which 1 pt died (bilateral TSR), 1 pt unfit to participate due to cervical disc problems. Of remaining 38 shoulders 11 shoulders had transtendonous and 27 shoulders had lesser tuberosity osteotomy approach. 37 shoulders were reviewed clinically for range of motion of the shoulder and subscapularis strength. Range of motion and subscapularis strength was significantly higher in the osteotomy group. All osteotomies were united on axillary radiograph. Lesser tuberosity osteotomy approach result in better subscapularis function than transtendonous approach

Introduction & Background. Clinical outcome after reverse total shoulder arthroplasty (RTSA) can be influenced by technical and implant-related factors, so the purpose of this study was to investigate whether individualizing humeral retroversion and subscapularis repair affect the clinical outcomes after RTSA. Material & Method. Authors retrospectively analyzed the prospectively collected data from 80 patients who underwent RTSA from January 2007 to January 2015 using same implant (Biomet Comprehensive. ®. Reverse Shoulder System, Warsaw, Indiana). The mean follow up was 23.3 ± 1.7 (range, 12 ∼ 70) months. The retroversion of humeral component was decided according to native version estimated using shoulder CT in Group I (n=52), and fixed in 20° retroversion in Group II (n=28). Group I was subdivided into Group Ia (n=21, mean 19.3°), less than 20° of retroversion, and Group Ib (n=31, mean 31.9°), more than 20°. Intraoperative tenotomized subscapularis was repaired in 40 patients in Group I, and could not be repaired due to massive tear including subscapularis in remaining 12 patients. Clinical outcomes were evaluated with range of motion (ROM) and several clinical outcome scores. Results. Group I showed significantly better ROM and clinical scores compared to Group II at the final follow up (all p < 0.05). There were no significant differences in ROM and clinical scores between Group Ia and Ib. Group Ia showed better ROM and pain VAS than Group II (all p < 0.05), and Group Ib also demonstrated significantly better ROM and clinical outcome scores than Group II (all p < 0.05). With respect to subscapularis repair, there were no differences in ROM and clinical scores between two groups. No complications such as infection or dislocation were detected according to subscapularis repair. Conclusion. Individualizing humeral retroversion can obtain superior clinical outcomes than fixed 20° retroversion. Subscapularis repair would not be essential for the better clinical outcome in patients with the lateralized RTSA

Introduction:. The subscapularis muscle experiences significant strain as it accommodates common movements of the shoulder. Little is known about what happens with this obligatory strain once the subscapularis insertion is disrupted and repaired in the course of shoulder arthroplasty. Subscapularis failure is a serious known complication after shoulder arthroplasty. It is not known what the effect of increasing the thickness of the shoulder head will have on subscapularis strain. It is our hypothesis that the use of large or expanded humeral heads during shoulder replacement will cause increased tension in the repaired subscapularis. The primary purpose of this study was to identify the optimal manner to perform a passive range of motion (PROM) program without invoking a significant increase in strain in the repaired subscapularis. The secondary purpose was to determine the impact of varying the thickness of the humeral head on subscapularis strain using the same PROM protocol. Methods:. Eight fresh-frozen, forequarter cadaver (four female, four male) specimens were obtained following IRB approval. An extended deltopectoral incision was performed so that the subscapularis insertion site could be well visualized. PROM exercises with the following motions were evaluated: external rotation, abduction, flexion and scaption. An optical motion analysis system was used to measure strain in the subscapularis. The same measurement protocol was repeated after performing a subscapularis osteotomy and after placement of an anatomic hemiarthroplasty of three different thicknesses (short, tall, expanded). Results:. A decrease in joint laxity (less strain but more tension on the subscapularis) was observed in abduction, external rotation, and forward flexion, following implantation of the shoulder arthroplasty components. For abduction and forward flexion, we observed a trend of decreasing laxity with increasing humeral head component thickness. For external rotation, all components displayed a similar reduction in joint laxity. With the short humeral head, strain was similar to native joint with passive scaption and flexion but not with external rotation or abduction. Discussion:. The PROM that tends to minimize tension on the subscapularis is forward flexion and scaption whereas external rotation and abduction will stress the subscapularis repair. Therefore passive forward flexion or scaption do not need to be limited but clearly external rotation should have passive limits and abduction should probably be avoided. The subscapularis muscle is under greater preload tension after shoulder joint arthroplasty. Even the short head size humeral component demonstrated decreased laxity compared to the intact joint. This suggests that even the shortest head size available may not be anatomical and perhaps a thinner humeral head size would be more representative of the normal anatomy

Currently, the consensus regarding subscapularis tendon repair during a reverse total shoulder arthroplasty (rTSA) is to do so if it is possible. Repair is thought to decrease the risk of dislocation and improve internal rotation but may also increase stiffness and improvement in internal rotation may be of subclinical benefit. Aim is to retrospectively evaluate the outcomes of rTSA, with or without a subscapularis tendon repair.

We completed a retrospective review of 51 participants (25 without and 26 with subscapularis repair) who received rTSR by a single-surgeon using a single-implant. Three patient reported outcome measures (PROM) were assessed pre-operatively and post-operative at twelve months, as well as range of movement (ROM) and plain radiographs. Statistical analysis utilized unpaired t tests for parametric variables and Mann-Whitney U test for nonparametric variables.

External Rotation ROM pre-operatively was the only variable with a significance difference (p=0.02) with the subscapularis tendon repaired group having a greater range. Pre- and post-operative abduction (p=0.72 & 0.58), forward flexion (p=0.67 & 0.34), ASES (p=0.0.06 & 0.78), Oxford (p=0.0.27 & 0.73) and post-operative external rotation (p=0.17)

Greater external rotation ROM pre-operatively may be indicative of the ability to repair the subscapularis tendon intra-operatively. However, repair does not seem to improve clinical outcome at 12 months.

There was no difference of the PROMs and AROMs between the subscapularis repaired and not repaired groups for any of the variables at the pre-operative or 12 month post operative with the exception of the external rotation ROM pre-operatively. We can conclude that from PROM or AROM perspective there is no difference if the tendon is repaired or not in a rTSR and indeed the patients without the repair may have improved outcomes at 12 months.

Shoulder arthroplasty procedures continue to increase in prevalence, and controversy still remains about the optimal method to manage the subscapularis. Scalise et al. performed an analysis of 20 osteotomies and 15 tenotomy procedures, and found the tenotomy group had a higher rate of abnormal subscapularis tendons on ultrasound examination. There was one tendon rupture in the subscapularis tenotomy group and no ruptures in the osteotomy group. Jandhyala et al. retrospectively examined 26 lesser tuberosity osteotomies and 10 subscapularis tenotomies for arthroplasty, and their study demonstrated a significant improvement in the belly press test for the osteotomy group. Lapner et al. performed a randomised controlled trial assigning patient to either a lesser tuberosity osteotomy or a subscapularis peel procedure. They evaluated 36 osteotomies and 37 subscapularis peels. The outcomes evaluated were Dynamometer internal rotation strength, the Western Ontario Osteoarthritis of the Shoulder Index (WOOS) score and American Shoulder and Elbow Surgeons (ASES) score, and in a subsequent paper they evaluated the healing rates and Goutallier grade. Their studies illustrated no difference in the internal rotation strength between groups. Both groups significantly improved WOOS and ASES scores post-operatively, but the difference was not significant between groups. Goutallier grade increased significantly in both groups, but there was no significant difference between the groups. Overall, the different approaches have not demonstrated a meaningful clinical difference. Further studies are needed to help understand issues leading to subscapularis complications after arthroplasty.

Purpose

Controversy exists regarding the optimal technique of subscapularis mobilization during shoulder arthroplasty. The purpose of this multicentre randomized double-blind study was to compare the functional outcomes and healing rates of the lesser tuberosity osteotomy (LTO) to the subscapularis tenotomy (ST).

Massive posterosuperior cuff tears (mRCT) retracted to the glenoid are surgically challenging and often associated with high retear rates. Primary repair is a less-favourable option and other salvage procedures such as SCR and tendon transfers are used. This study presents clinical and radiological outcomes of muscle advancement technique for repair of mRCT. Sixty-one patients (mean age 57±6, 77% males and 23% females) (66 shoulders) underwent all-arthroscopic rotator cuff repair that included supraspinatus and infraspinatus subperiosteal dissection off scapular bony fossae, lateral advancement of tendon laminae, and tension-free double-layer Lasso Loop repair to footprint. Pre-and post-operative range of motion (ROM), cuff strength, VAS, Constant, ASES, and UCLA scores were assessed. Radiologic assessment included modified Patte and Goutallier classifications. All patients had MRI at 6 months to evaluate healing and integrity of repair was assessed using Sugaya classification with Sugaya 4 and 5 considered retears. Advanced fatty degeneration (Goutallier 3-4) was present in 44% and 20% of supraspinatus and infraspinatus. Tendon retraction was to the level of or medial to glenoid in 22%, and just lateral in 66%. 50.8% mRCT extended to teres minor. Subscapularis was partially torn (Lafosse 1-3) in 46% and completely torn (Lafosse 4-5) in 20%. At mean follow-up (52.4 weeks), a significant increase in ROM, Relative Cuff Strength (from 57% to 90% compared to contralateral side), VAS (from 4 ±2.5 to 1±1.7), Constant (50±17.8 to 74 ±13.0), ASES (52 ±17.5 to 87 ±14.9), and UCLA (16± 4.9 to 30 ±4.9) scores were noted. There were six retears (10%), one failure due to P. acnes infection. 93% returned to pre-injury work and 89% of cases returned to pre-injury sport. Satisfaction rate was 96%. Muscle advancement technique for mRCT is a viable option with low retear rates, restoration of ROM, strength, and excellent functional outcomes

Introduction. Shoulder arthoplasty has increased in the last years and its main goal is to relieve pain and restore function. Shoulder prosthesis enters in the market without any type of pre-clinical tests. Within this paper we present study experimental and computational tests as pre-clinical testing to evaluate total shoulder arthoplasty performance. Materials and methods. An in vitro experimental simulator was designed to characterize experimentally the intact and implanted shoulder glenoid articulation. Fourth generation Sawbones® composite left humerus and scapula were used and the cartilage was replicated with silicone for the intact articulation (figure 1). In the intact experimental articulation we considered the inferior glenohumeral ligament as an elastic band with equivalent mechanical properties. For the implanted shoulder, the Comprehensive® Total Shoulder System (Biomet®) with a modular Hybrid® glenoid base and Regenerex® central post was considered (figure 2). The prostheses were implanted by an experienced surgeon and clinical results from orthopedic registers were collected. The system structures were placed to simulate 90º in abduction, including the following muscle forces: Deltoideus 300N, Infraspinatus 120N, Supraspinatus 90N and Subscapularis 225N. The finite element model was created with tetrahedral linear elements with linear elastic and isotropic material for the humerus in figure 3, (Young's modulus for cortical bone − 16.5 GPa; trabecular bone − 124 MPa). Anisotropic behavior was considered for the scapula model (E11 = 342.1 MPa, E22 = 212.8 MPa, E33 = 194.4 MPa). The shoulder prosthesis was of polyethylene with 1GPa and titanium with 110 GPa. The Poisson's ratio was 0.3 in all material, except for polyethylene where we assumed a value of 0.4. A long-term post-operative condition was simulated. Results. The experimental results were compared with numerical ones for model validation. The strains measured evidence the effect of the implant presence, manly in the scapula. In the anterior region presents an increase of strains (+26%) was observed for the anterior region and decrease (−52%) in the posterior region, suggesting strain shielding in figure 4. At the glenoid cavity, the numerical principal strains present safety values of strains (200 to 2500) µε in both axial and coronal planes. This indicates that on the long-term the glenoid prosthesis is well fixed to the surrounding bone tissue and bone integrity is maintained despite the presence of the implant. However there are some peak values (2500, 25 000 µε) that were observed in some small areas in the posterior and distal regions. Results were compared with clinical ones. Discussion and Conclusions. The proposed pre-clinical test with the articulation at 90º in abduction can predict bone behavior when total shoulder prosthesis is implanted and in the long term post-operative condition. The results obtained evidence some critical regions around the glenoid component. This pre-clinical test can be implemented to improve the concepts before market

Subscapularis tenotomy (SST) has been the preferred approach for shoulder arthroplasty for decades but recent controversy has propelled lesser tuberosity osteotomy (LTO) as a potential alternative. Early work by Gerber suggested improved healing and better outcomes with LTO although subscapularis muscular atrophy occurred in this group as well with unknown long-term implications. However, we previously performed a biomechanical study showing that some of the poor results following tenotomy may have been due to historic non-anatomic repair techniques. Surgical technique is critical to allow anatomic healing – this is true of both SST or LTO techniques. A recent meta-analysis of biomechanical cadaveric studies showed that LTO was stronger to SST at “time-zero” with respect to load to failure but there were no significant differences in cyclic displacement. A recent study evaluated neurodiagnostic, functional, and radiographic outcomes in 30 patients with shoulder arthroplasty who had SST. The authors found that the EMG findings were normal in 15 patients but abnormal in the other 15 and that these abnormalities occurred in 5 muscle groups (not just the subscapularis). In another study, patient outcomes were inferior in those patients who had documented subscapularis dysfunction following SST compared to patients who had LTO (none of whom had subscap dysfunction). The literature is not clear, however, on ultimate outcomes based on subscapularis dysfunction post-arthroplasty with some studies showing no difference and others showing significant differences

Despite the high success rates of Reverse Shoulder replacements, complications of instability & scapular notching are a concern. Factors reducing relative motion of implant to underlying bone which include lateral offset to centre of rotation, screw & central peg insertion angle and early osteo-integration are maximized in the Trabecular Metal Reverse total shoulder system. We present clinico-radiological outcomes over 72 months. Analysis of a single surgeon series of 140 Reverse total shoulder replacements in 135 patients was done. Mean age was 72(range 58– 87 yrs); 81 females: 54 males. Indications were Rotator cuff arthropathy {n= 88} (63%); Osteo-arthritis with dysfunctional cuff {n= 22}(15%); post-trauma{n=23} (15%); revision from hemiarthroplasty {n=3} (2.4%) and from surface replacement {n=4} (2.8%). All patients were assessed using pre-operative Constants and Oxford scores and clinical & radiographic reviews with standard X-Rays at 6 weeks, 3, 6,12 months and yearly thereafter. X rays included an AP view in 45 degrees of external rotation and modified axillary view. Inferior Scapular notching using the Nerot-Sirveaux grades and Peg Glenoid Rim Distance were looked into by a consultant musculoskeletal radiologist/ Orthopaedic surgeon/ Senior Fellow (post CCT) or a specialist Trainee (ST4 and above). Pain on the visual analogue scale decreased by 98% (9.1 to 0.8) (p<0.01). Constant score improved by 81.8% (12.4 to 68.1) (p<0.05), Oxford shoulder score by 76.7% (56 to 13) (p<0.05). 95.6% of Humeral stems had no radiolucent lines and 4.4% had < 2mm of lucency. Scapular notching was calculated using Sirveaux grades with Peg scapular base angle distance (PSBA) measurements on PACS with Siemens calibration (grade 1= 4 (2.8%); grade 2 =1; grade 3 =0; grade 4=0). 3.57% showed radiographic signs of scapular notching at 72 months. Range of Peg Glenoid Rim Distance was 1.66 to 2.31 cm. Power analysis showed 65 patients were needed to have an 80% power to detect relation of Peg Glenoid Rim Distance to Scapular notching. A likelihood ratio test from Logistic regression model to check correlation of Peg Glenoid Rim Distance to Scapular notching gave a p value of 0.0005. A likelihood ratio from Logistic regression gave a p value of 0.0004 for Infraglenoid Scapular spurs. Highest incidence of spurring was seen in Reverse Total Shoulder Replacements done for Trauma and lowest in patients who got the procedure for Osteoarthritis. Complications included two glenosphere revisions; two stitch abscesses and two Acromial fractures in patients who had a fall two years after the procedure. Improved surgical outcomes can be attributed to surgical technique and implant characteristics. Trabacular metal promotes early osteointegration which resists shearing action of Deltoid on Glenoid component. This allows early mobilisation. Deltoid split approach preserves integrity of Subscapularis and Acromial osteotomy and lateral clavicle excision improve exposure and prevent Acromion fracture. Positioning the Glenoid component inferiorly on the Glenoid decreases incidence of Scapular notching. Our mid-term validated outcomes are promising with only 3.57% Grade I/II radiographic signs of scapular notching. Long term studies (10 year follow ups) are necessary to confirm its efficacy

The cellular mechanisms of tendinopathy remain unclear, particularly with respect to the role of inflammation in early disease. We have previously identified increased levels of inflammatory cytokines in an early human model of tendinopathy and sought to extend these studies to the cellular analysis of tissue. Purpose. To characterise inflammatory cell subtypes in early human tendinopathy we explored the phenotype and quantification of inflammatory cells in torn and control tendon samples. Design. Controlled laboratory study. Methods. Torn supraspinatus tendon and matched intact subscapularis tendon samples were collected from twenty patients undergoing arthroscopic shoulder surgery. Control samples of subscapularis tendon were collected from ten patients undergoing arthroscopic stabilisation surgery. Tendon biopsies were evaluated immunohistochemically by quantifying the presence of macrophages (CD68 and CD206), T cells (CD3), mast cells (Mast cell tryptase) and vascular endothelium (CD34). Results. Subscapularis tendon biopsies obtained from patients with torn supraspinatus tendon exhibited significantly greater macrophage, mast cell and T cell expression compared to either torn supraspinatus samples or control subscapularis derived tissue (p< 0.01). Inflammatory cell infiltrate correlated inversely (r=0.5, p< 0.01) with rotator cuff tear size, with larger tears correlating with a marked reduction in all cell lineages. There was a modest but significant correlation between mast cells and CD 34 expression (r= 0.4, p< 0.01) in pre-rupture subscapularis tendon. Conclusion. We provide evidence for an inflammatory cell infiltrate in early mild/moderate human supraspinatus tendinopathy. In particular, we demonstrate significant infiltration of mast cells and macrophages suggesting a role for innate immune pathways in the events that mediate early tendinopathy. Further mechanistic studies to evaluate the net contribution and hence therapeutic utlity of these cellular lineages and their downstream processes may reveal novel therapeutic approaches to the management of early tendinopathy