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

Studies have shown that the trees minor plays an important role after total (TSA) and reverse (RSA) shoulder arthroplasty, as well as in maintenance of function in the setting of infraspinatus wasting. In this regard, teres minor hypertrophy has been described as a compensatory change in response to this infraspinatus wasting, and has been suggested that this compensatory hypertrophy may mitigate the loss of infraspinatus function in the patient with a large rotator cuff tear. The purpose of this study was to determine the prevalence of teres minor hypertrophy in a cohort of patients undergoing rotator cuff repair, and to determine its prognostic effect, if any, on outcomes after surgical repair. Over a 3 year period, all rotator cuff repairs performed in a single practice by 3 ASES member surgeons were collected. Inclusion criteria included both preoperative and postoperative validated outcomes measures (minimum 2 year), and preoperative Magnetic Resonance Imaging (MRI) scanning. 144 patients met all criteria. MRIs were evaluated for rotator cuff tear tendon involvement, tear size, and Goutallier changes of each muscle. In addition, occupational ratios were determined for the supraspinatus, infraspinatus, and teres minor muscles. Patients were divided into 2 groups, based upon whether they had teres minor hypertrophy or not, based on a previously established definition. A 2 way ANOVA was used to determine the effect of teres minor hypertrophy(tear size by hypertrophy) and Goutallier. Teres minor hypertrophy was a relatively common finding in this cohort of rotator cuff patients, with 51% of all shoulders demonstrating hypertrophy. Interestingly, in patients without an infraspinatus tear, teres minor hypertrophy was still present in 19/40 (48%) of patients. Teres minor hypertrophy had a significant, negative effect ASES scores after rotator cuff repair in patients with and without infraspinatus tearing, infraspinatus atrophy, and fatty infiltrative changes (P<0.05). In general, the presence of teres minor hypertrophy showed 10–15% less improvement (Figure 1) than when no hypertrophy was present, and this was consistent across all tear sizes, independent of Goutallier changes. Teres minor hypertrophy is a common finding in the setting of rotator cuff tearing, including in the absence of infraspinatus tearing. Contrary to previous publications, the presence of teres minor hypertrophy in patients with rotator cuff repair does not appear to be protective as a compensatory mechanism. While further study is necessary to determine the mechanism or implication of teres minor hypertrophy in setting of rotator cuff repair, our results show it is not a positive of outcomes following rotator cuff repair

Background. Rotator cuff atrophy evaluated with computed tomography scans has been associated with asymmetric glenoid wear and humeral head subluxation in glenohumeral arthritis. Magnetic resonance imaging has increased sensitivity for identifying rotator cuff pathology and has not been used to investigate this relationship. The purpose of this study was to use MRI to assess the association of rotator cuff muscle atrophy and glenoid morphology in primary glenohumeral arthritis. Methods. 132 shoulders from 129 patients with primary GHOA were retrospectively reviewed and basic demographic information was collected. All patients had MRIs that included appropriate orthogonal imaging to assess glenoid morphology and rotator cuff pathology and were reviewed by two senior surgeons. All patients had intact rotator cuff tendons. Glenoid morphology was assigned using the modified-Walch classification system (types A1, A2, B1, B2, B3, C, and D) and rotator cuff fatty infiltration was assigned using Goutallier scores. Results. 46 (35%) of the shoulders had posterior wear patterns (23 type B2s, 23 type B3s). Both the infraspinatus and teres minor independently had significantly more fatty infiltration in B2 and B3 type glenoids compared to type A glenoids (p<0.001). There was a greater imbalance in posterior rotator cuff muscle fatty atrophy in B2 and B3 type glenoids compared to type A glenoids (p<0.001). However, there was no difference in axial plane imbalance between B2 and B3 glenoids (p=1.00). There was increased amount fatty infiltration of the infraspinatus among B2 and B3-type glenoids compared to type A glenoids on multivariate analysis controlling for age and gender (p<0.001). Conclusions. These results identify significant axial plane rotator cuff muscle imbalances in B2 and B3-type glenoids compared to concentrically worn glenoids, favoring a relative increase in fatty infiltration of the infraspinatus and teres minor compared to the subscapularis in glenoids with patterns of posterior wear. For any figures or tables, please contact authors directly

Introduction. Reverse shoulder arthroplasty (rTSA) increases the deltoid abductor moment arm length to facilitate the restoration of arm elevation; however, rTSA is less effective at restoring external rotation. This analysis compares the muscle moment arms associated with two designs of rTSA humeral trays during two motions: abduction and internal/external rotation to evaluate the null hypothesis that offsetting the humerus in the posterior/superior direction will not impact muscle moment arms. Methods. A 3-D computer model simulated abduction and internal/external rotation for the normal shoulder, the non-offset reverse shoulder, and the posterior/superior offset reverse shoulder. Four muscles were modeled as 3 lines from origin to insertion. Both offset and non-offset reverse shoulders were implanted at the same location along the inferior glenoid rim of the scapula in 20° of humeral retroversion. Abductor moment arms were calculated for each muscle from 0° to 140° humeral abduction in the scapular plan using a 1.8: 1 scapular rhythm. Rotation moment arms were calculated for each muscle from 30° internal to 60° external rotation with the arm in 30° abduction. Results. During abduction with the normal shoulder, the subscapularis and infraspinatus act as abductors throughout the range of motion and the teres minor converts from an adductor to abductor at 60°. In the non-offset reverse shoulder, the subscapularis converts from an adductor to abductor at 82°, the infraspinatus converts at 68°, and the teres minor converts at 135°. Because the offset humeral tray shifts the humerus superiorly relative to the non-offset tray, each muscle converts from an adductor to abductor earlier in abduction, where the subscapularis converts at 62°, the infraspinatus converts at 43°, and the teres minor converts at 110°. During rotation (Figures 1–3), both the offset and non-offset reverse shoulders decrease the internal rotation capability of the subscapularis and teres major but increase the external rotation capability of the infraspinatus and teres minor relative to the normal shoulder. Because the offset tray shifts the humerus posteriorly, the internal rotation capability of the subscapularis and teres major is decreased by 7.1 and 9.5 mm while the external rotation capability of the infraspinatus and teres minor is increased by 8.6 and 7.8 mm, respectively. Discussion and Conclusions. Changing humeral position using an offset humeral tray modified the function of each muscle. In abduction, the offset tray caused each muscle to convert from adductors to abductors earlier. Improved abduction capability limits each muscle's antagonistic behavior with the deltoid, potentially reducing the deltoid force required to elevate the arm. In rotation, the offset tray caused the posterior shoulder muscles to be more effective external rotators. Improved external rotation capability is important for patients with external rotation deficiency; as external rotation is required for many activities of daily living, increasing the rotator moment arm lengths of the only two external rotators is advantageous to restore function. Therefore, we reject the null hypothesis and conclude the offset humeral tray does impact muscle moment arms with rTSA. Future work should evaluate the clinical significance of these observed changes in muscle moment arms

Shoulder girdles of 20 cadavers (68–94yrs) were harvested. The anterior (ACHA) and posterior circumflex humeral arteries (PCHA) were injected with ink and the extra and intraosseous courses of the dyed vasculature dissected through the soft tissues and bone to the osteotendinous junctions of the rotator cuff. The ink injection and bone dissection method was newly developed for the study. Rates of cross-over at the osteotendinous juntion were 75% in the supraspinatus, 67% in subscapularis, 33% in infraspinatus and 20% in teres minor. The supraspinatus and subscapularis insertions were vascularised by the arcuate artery, a branch of the ACHA. The insertions of the infraspinatus and teres minor were supplied by an unnamed terminal branch of the PCHA. The insertions of the rotator cuff receive an arterial supply across their OTJ's in 50% of cases. This may explain observed rates of AVN in comminuted proximal humeral fractures. The terminal branch of the PCHA supplying the infraspinatus and teres minor insertions was named the “Posterolateral Artery”. Finally, the new method employed for this study which allowed for direct visualisation of intraosseous vasculature, will enhance our understanding of skeletal vascular anatomy and have clinical applications in orthopaedic and reconstructive surgery

Reverse total shoulder arthroplasty (RTSA) was designed to treat the cuff-deficient shoulder with arthritis and irreparable rotator cuff tears of the supraspinatus and infraspinatus tendons. The results of RTSA in this patient population have been very good and reliable in the majority of cases. However, it has also been reported that patients whose rotator cuff tear involves the supraspinatus, infraspinatus and teres minor and who demonstrate a ‘horn-blower's sign’ do very poorly if a muscle transfer is not performed to improve external rotation in these shoulders in abduction. The loss of the teres minor in these patients results in grave difficulty for the patient attempting to perform their activities of daily living even if they can obtain reasonable good forward flexion. The muscle transfer that is most commonly used for these select patients is a latissmus dorsi tendon transfer in conjunction with RTSA. The purpose of this talk is to review the pathology of this problem and review the technique for its surgical treatment

Chronic massive irreparable rotator cuff tears represent a treatment challenge and the optimal surgical technique remains controversial. Superior capsular reconstruction (SCR) has been proposed as a means to provide superior stability to the glenohumeral joint, thus facilitating restoration of shoulder function. However, despite the growing use of SCR there is a paucity of data evaluating the outcomes when performed using a dermal allograft. The purpose of this study was to (1) report the overall survival rate (reoperation and clinical failure) of SCR (2) evaluate for pre-operative factors predicting reoperation and clinical failure. From January 1, 2015 to November 31, 2017, 65 patients were diagnosed with irreparable rotator cuff tears and consented for a superior capsular reconstruction. These surgeries were performed by 6 surgeons, all fellowship trained in either sports or shoulder and elbow fellowships. Outcomes were graded as excellent, satisfactory, or unsatisfactory using the modified Neer scale. An unsatisfactory result was defined as a clinical “failure”. The Kaplan-Meier survival models were created to analyze reoperation-free and failure-free survival for the entire group. The reconstruction was performed using a dermal allograft. There were 31 patients excluded due to insufficient follow-up (< 6 months), leaving 34 included in this study. The mean follow-up was 12 months (range, 6–23). The average number of prior surgeries was 0.91 (range, 0–5), with 52.9% of patients receiving a prior rotator cuff repair and 38.2% of patients with a prior non-rotator cuff arthroscopy procedure. The one and two-year survival-free of surgery was 64% and 44% and the one and two-year survival free of failure was 34% and 16% following SCR, respectively. For the patients that underwent a reoperation, 62.5% (n= 5/8) underwent reverse shoulder replacements, 25% (n= 2/8) latissimus dorsi tendon transfers, and 12.5% (n= 1/8) a diagnostic arthroscopy. The average period between the primary and revision surgery was 10.2 months (range, 2.1–18.5). All but two patients (75%, n= 6/8) had at least one surgery prior to the SCR. There were 14/34 (41.2%) patients who experienced pain, weakness, and restricted range of motion. These patients were defined as clinical failures with an unsatisfactory grading on Neer's criteria. Previous surgery predicted reoperation (80% vs 43%, p = 0.03). Female gender predicted clinical failure (100% vs 43%, p < 0 .01). Superior Capsule Reconstruction performed for large to massive rotator cuff tears has a high rate of persistent pain and limited function leading to clinical failure in 65% (n= 22/34) of patients. The rate of failure is increased in revision cases, female gender and increased Goutallier fatty infiltration of the infraspinatus. Narrowed indications are recommended given the surgical complexity and high rate of early failure

Surgical reattachment of torn rotator cuff tendons can lead to satisfactory clinical outcome but failures remain common. Ortho-R product is a freeze-dried formulation of chitosan (CS) that is solubilized in platelet-rich plasma (PRP) to form injectable implants. The purpose of the current pilot study was to determine Ortho-R implant acute residency, test safety of different implant doses, and assess efficacy over standard of care in a sheep model. The infraspinatus tendon (ISP) was detached and immediately repaired in 22 skeletally mature ewes. Repair was done with four suture anchors in a suture bridge configuration (n = 6 controls). Freeze-dried formulations containing 1% w/v chitosan (number average molar mass 35 kDa and degree of deacetylation 83%) with 1% w/v trehalose (as lyoprotectant) and 42.2 mM calcium chloride (as clot activator) were solubilized with autologous leukocyte-rich PRP and injected at the tendon-bone interface and on top of the repaired site (n = 6 with a 1 mL dose and n = 6 with a 2 mL dose). Acute implant residency was assessed histologically at 1 day (n = 2 with a 1 mL dose and n = 2 with a 2 mL dose). Outcome measures included MRI assessment at baseline, 6 weeks and 12 weeks, histopathology at 12 weeks and clinical pathology. MRI images and histological slides were scored by 2 blinded readers (veterinarian and human radiologist, and veterinarian pathologist) and averaged. The Generalized Linear Model task (SAS Enterprise Guide 7.1 and SAS 9.4) was used to compare the different groups with post-hoc analysis to test for pairwise differences. Ortho-R implants were detected near the enthesis, near the top of the anchors holes and at the surface of ISP tendon and muscle at 1 day. Numerous polymorphonuclear cells were recruited to the implant in the case of ISP tendon and muscle. On MRI, all repair sites were hyperintense compared to normal tendon at 6 weeks and only 1 out 18 repair sites was isointense at 12 weeks. The tendon repair site gap seen on MRI, which is the length of the hyperintense region between the greater tuberosity and tendon with normal signal intensity, was decreased by treatment with the 2 mL dose when compared to control at 12 weeks (p = 0.01). Histologically, none of the repair sites were structurally normal. A trend of improved structural organization of the tendon (p = 0.06) and improved structural appearance of the enthesis (p = 0.1) with 2 mL dose treatment compared to control was seen at 12 weeks. There was no treatment-specific effect on all standard safety outcome measures, which suggests high safety. Ortho-R implants (2 mL dose) modulated the rotator cuff healing processes in this large animal model. The promising MRI and histological findings may translate into improved mechanical performance, which will be assessed in a future study with a larger number of animals. This study provides preliminary evidence on the safety and efficacy of Ortho-R implants in a large animal model that could potentially be translated to a clinical setting

The indication for rotator cuff repair in elderly patients is controversial. Methods. Consecutive patients over the age of 70 years, under the care of a single surgeon, receiving an arthroscopic rotator cuff repair were reviewed. Predominantly, a single row repair was performed using one (34 cases) or two (30) 5mm Fastin, double-loaded anchors. Double-row repair was performed in four cases. Subacromial decompression and treatment of biceps pathology were performed as necessary. Data were collected from medical records, digital radiology archives and during clinic appointments. Pain, motion, strength and function were quantified with the Constant-Murley Shoulder Outcome Score, administered pre operatively and at 1-year post operatively. Ultrasound scans were performed at one year to document integrity of the repair. Results. Sixty-nine arthroscopic cuff repairs were identified in 68 patients. The mean age was 77 years (70–86). The median ASA grade was 2 (79%). The dominant side was operated on in 68% of cases. A range of tear sizes were operated on (5 small, 17 moderate, 29 large and 18 massive). The tendons involved in the tear also varied (supraspinatus 12, supra and infraspinatus 53, supraspinatus and subscapularis 2, supraspinatus infraspinatus and subscapularis 2). Re-rupture occurred in 20 cases (29%). The mean Constant score increased from 23 (95% CI 19–26) to 59 (54–64) (P< 0.001). Where the repair remained sound, Constant score improved 42 points (95%CI 36–48). If the cuff re-ruptured, constant score also increased on average 12 points (95% CI 2–21). Re-rupture rate was highest for massive cuff repairs: ten out of eighteen (56%). Conclusion. Arthroscopic rotator cuff repair in the elderly is a successful procedure. Approximately seven out of ten repairs remained intact after one year. Even where re-rupture occurs, a significant improvement in the Constant score was found

Background:. The balance between the subscapularis muscle and the infraspinatus/teres minor muscles, often referred to as the rotator cuff ‘force couple’, has been proposed to be critical component for glenohumeral stability. Function of these muscles can be estimated with the evaluation of muscle atrophy. In clinical practice, muscle cross-sectional area (CSA) rather than 3D muscle volume measurement have been used because it is less time consuming. Because combined anthropometric measures of length and width more accurately define the muscular volume it seems logical to study the transversal rotator cuff force couple in the transversal plane an not in the sagittal plane of the body because both parameters can be included. But is it not clear which transversal CSA has the best correlation with muscle volume. Purpose:. To determine the optimal transversal CSA that has the best correlation with muscle volume. Material and Methods:. A total of 30 CT images containing the full scapula were used. Using Mimics® and 3-Matic® the correlation between CSA's and volume has been evaluated. Two methods have been evaluated. The first method was the CSA measured on transversal plane without 3D editing. The second method is a CSA measured on a new defined transversal plane using 3D reconstruction and reslice editing techniques. Results. Both techniques showed a very high inter and intraobserver reliability (ICC for single measures in both techniques > 0.97, p < 0.001). Correlation of the muscle volume/CSA of the subscapularis showed a high correlation in both the non-reconstructed (ρ = 0,699, p = 0,002) and reconstructed technique (ρ = 0,842, p < 0,001). Correlation of the muscle volume/CSA of the infraspinatus/teres minor showed a moderate correlation in the non-reconstructed (ρ = 0,591, p = 0,013) and a high correlation in reconstructed technique (ρ = 0,779, p < 0,001). There is a significant higher correlation with the volume with the reconstructed technique compared to the non-reconstructed technique (ρ = 0.638, p < 0.001 for the conventional transversal section versus ρ = 0.818, p < 0.001 for the resliced section). Conclusion. Muscular volume of the rotator cuff force couple can be quantified using a non-reconstructed CSA, but is significant more accurately quantified by a 3D reconstructed technique. In the future, balance of the force couple in different shoulder pathologies can be quantified with this measurement technique

The treatment of proximal humerus fractures remains controversial. The literature is full of articles and commentary supporting one method over another. Options include open reduction and internal fixation, hemiarthroplasty, and reverse shoulder arthroplasty. Treatment options in an active 65-year-old are exceptionally controversial given the fact that people in this middle-aged group still wished to remain active and athletic in many circumstances. A hemiarthroplasty offers the advantage of a greater range of motion, however, this has a high incidence of tuberosity malunion or nonunion and this is a very common reason for revision of that hemiarthroplasty for fracture to a reverse shoulder replacement. One recent study showed a 73% incidence of tuberosity malunion or nonunion in shoulders that had a revised hemiarthroplasty to a reverse shoulder replacement. Progressive glenoid wear and erosion is also a risk after a hemiarthroplasty in the younger patient, especially someone who is young and active. In addition, studies show shorter operative time in hemiarthroplasty. The range of motion is highly dependent on proper tuberosity healing and this is often one of the most challenging aspects of the surgical procedure as well as the healing process. A reverse shoulder replacement in general has less range of motion compared to a hemiarthroplasty with anatomically healed tuberosities, however, the revision rate is lower compared to a hemiarthroplasty. (This is likely related to few were options for revision). The results after a reverse shoulder replacement may not be as dependent on tuberosity healing, however, importantly the tuberosities do need to be repaired and the results are significantly better if there is healing of the greater tuberosity, giving some infraspinatus and/or teres minor function to the shoulder. Complete lack of tuberosity healing forces the shoulder into obligate internal rotation with attempted elevation and this can be functionally disabling. Academic discussion is beginning surrounding the use of a reverse shoulder replacement in the setting of glenohumeral joint arthritis in a primary setting as it is believed that the glenosphere and baseplate may have greater longevity than a polyethylene glenoid. Along with this discussion, we will likely see greater application of the use of a reverse shoulder replacement in the setting of fracture for younger patients. In general, open reduction internal fixation should still remain the treatment of choice in the setting of a fracture that can be fixed. However, a strong argument can be made that if an arthroplasty is necessary, a reverse shoulder replacement is the implant of choice

Animal studies examining tendon-bone healing have demonstrated that the overall structure, composition, and organization of direct type entheses are not regenerated following repair. We examined the effect of Low-Intensity Pulsed Ultrasound (LIPUS) on tendon-bone healing. LIPUS may accelerate and augment the tendon-bone healing process through alteration of critical molecular expressions. Eight skeletally mature wethers, randomly allocated to either control group (n=4) or LIPUS group (n=4), underwent rotator cuff surgery following injury to the infraspinatus tendon. All animals were sacrificed 28 days post surgery to allow examination of early effects of LIPUS. Humeral head – infraspinatus tendon constructs were harvested and processed for histology and immunohistochemical staining for BMP2, Smad4, VEGF and RUNX2. All the growth factors were semiquantitative evaluated. T-tests were used to examine differences which were considered significant at p < 0.05. Levene's Test (p < 0.05) was used to confirm variance homogeneity of the populations. The surgery and LIPUS treatment were well tolerated by all animals. Placement of LIPUS sensor did not unsettle the animals. Histologic appearance at the tendon-bone interface in LIPUS treated group demonstrated general improvement in appearance compared to controls. Generally a thicker region of newly formed woven bone, morphologically resembling trabecular bone, was noted at the tendon-bone interface in the LIPUS-treated group compared to the controls. Structurally, treatment group also showed evidence of a mature interface between tendon and bone as indicated by alignment of collagen fibres as visualized under polarized light. Immunohistochemistry revealed an increase in the protein expression patterns of VEGF (p = 0.038), RUNX2 (p = 0.02) and Smad4 (p = 0.05) in the treatment group. There was no statistical difference found in the expression patterns of BMP2. VEGF was positively stained within osteoblasts in newly formed bone, endothelial cells and some fibroblasts at the interface and focally within fibroblasts around the newly formed vessels. Expression patterns of RUNX2 were similar to that of BMP-2; the staining was noted in active fibroblasts found at the interface as well as in osteoblast-like cells and osteoprogenitor cells. Immunostaining of Smad4 was present in all cell types at the healing interface. The results of this study indicate that LIPUS may aid in tendon to bone healing process in patients who have undergone rotator cuff repair. This treatment may also be beneficial following other types of reconstructive surgeries involving the tendon-bone interface

Despite reverse total shoulder arthroplasty (RTSA) being primarily indicated for massive rotator cuff tears, it is often possible to repair portions of the infraspinatus and subscapularis of patients undergoing this procedure. However, there is disagreement regarding whether these tissues should be repaired, as their effects remain unclear. Therefore, we investigated the effects of rotator cuff repair and changes in humeral and glenosphere lateralisation (HLat & GLat) on deltoid and joint loading. Six shoulders were tested on an in-vitro muscle driven active motion simulator. Cuff tear arthropathy was simulated in each specimen, which was then implanted with a custom adjustable RTSA fitted with a six axis load sensor. We assessed the effects of 4 RTSA configurations (i.e. all combinations of 0&10mm of HLat & GLat) on deltoid force, joint load, and joint load angle during abduction with/out rotator cuff repair. Deltoid and joint loads recorded by the load cell are reported as a % of Body Weight (%BW). Repeated measures ANOVAs and pairwise comparisons were performed with p<0.05 indicating significance. Cuff repair interacted with HLat & GLat (p=0.005, Fig. 1) such that with no HLat, GLat increased deltoid force without cuff repair (8.1±2.1%BW, p=0.012) and this effect was significantly increased with cuff repair (12.8±3.2%BW, p=0.010). However, adding HLat mitigated this such that differences were not significant. HLat and GLat affected deltoid force regardless of cuff status (−2.5±0.7%BW, p=0.016 & +7.7±2.3%BW, p=0.016, respectively). Rotator cuff repair did significantly increase joint load (+11.9±2.1%BW, p=0.002), as did GLat (+13.3±1.5%BW, p<0.001). The increases in deltoid and joint load caused by rotator cuff repair confirm that it acts as an adductor following RTSA and increases deltoid work. Additionally, cuff repair's negative effects are exacerbated by GLat, which strengthens its adduction affect, while Hlat increases the deltoid's abduction effect thus mitigating the cuff's antagonistic effects. Cuff repair increases concavity compression within the joint; however, Hlat produces a similar effect by wrapping the deltoid around the greater tuberosity – which redirects its force – and does so without increasing the magnitude of muscle and joint loading. The long-term effects of increased joint loading due to rotator cuff repair are unknown, however, it can be postulated that it may increase implant wear, and the risk of deltoid fatigue. Therefore, RTSA implant designs which improve joint compression without increasing muscle and joint loading may be preferable to rotator cuff repair

Indications for total shoulder arthroplasty (TSA) require that the patient have a functioning rotator cuff to stabilise the glenohumeral joint. Without rotator cuff integrity the prosthesis will be unstable and the functional result will be less than expected. Physical exam can be difficult in the arthritic shoulder as contractures will limit the range of motion needed to adequately exam the rotator cuff status. The diagnosis can help as osteoarthritis has a 5% incidence of rotator cuff tear while rheumatoid arthritis has an incidence of greater than 40%. MRI can be obtained to determine the rotator cuff status before arthroplasty is performed but may not be necessary. Most total shoulder implant companies have both reverse and anatomic implants available. More recently the uses of platform stems that can be used with either RSA or TSA have been available. With this development in prosthetic design it is no longer necessary to determine the status of the rotator cuff before surgery. The surgeon can make the decision at the time of surgery which implants RSA or TSA will be necessary based on the status of the rotator cuff. There have been recent reports of longer follow up of TSA patients that had fatty atrophy of the infraspinatus muscle that had rotator cuff tears at 10–15 years. MRI may still be warranted in the older individual that is being considered for TSA to determine the quality of the rotator cuff musculature

Purpose. Chronic massive rotator cuff tears are challenging to repair completely because of the development of tendon retraction with inelasticity, muscle atrophy and fatty infiltration. The objective of this study was to investigate the clinical outcome and MRI findings after arthroscopic superior capsule reconstruction (ASCR) for symptomatic irreparable rotator cuff tears. Methods. From 2011 to 2013, 12 shoulders in 12 consecutive patients (mean, 70.8 years) with irreparable massive rotator cuff tears underwent ASCR using fascia lata. We used suture anchors to attach the graft medially to the glenoid superior tubercle and laterally to the greater tuberosity as same technique by Mihata et al. We added side-to-side sutures between the graft and infraspinatus tendon and between the graft and residual anterior supraspinatus/subscapularis tendon to improve force coupling. Physical examination, clinical rating system, and magnetic resonance imaging (MRI) were performed before surgery; at 6 and 12 months after surgery; and 6 months thereafter. Average follow-up was 19.1 months (12 to 28 months) after surgery. We assessed patients preoperatively by using the scoring systems of the shoulder index of the American Shoulder and Elbow Surgeons (ASES), the Japanese Orthopaedic Association, and the University of California, Los Angeles. Results. Mean active elevation increased from 59° to 111° significantly and external rotation increased from 28 to 33. The average preoperative scores were 16.0 points by ASES, 48.0 points by JOA, and 10.8 points by UCLA. Average clinical outcome scores all improved significantly after ASCR at the final follow-up (ASES, 73.3 points; JOA, 73.7 points; UCLA, 22.7 points). There was surgical complication as infection. Although infection was controlled by arthroscopic irrigation, the transplanted tendon was absorbed, and preoperative conditions did not functionally improve. Five patients had graft tear during follow-up. Postoperative active range of motion in the healed patients was significantly greater than in the unhealed patients who had graft tears. Conclusions. ASCR restored superior glenohumeral stability and function of the shoulder joint with irreparable rotator cuff tears compared to preoperative function in the cases without postoperative complications. However ratio of graft tears were 50% and clinical results of these cases were not improved sufficiently

Introduction. Rotator cuff tears remain a problem, with massive tears having a failure rate of repair reported of up to 60%, despite advances in surgical techniques. Tissue engineering techniques offers the possibility of regenerating damaged tendon tissue to a pre-injury state. We explore these techniques by implanting two novel tendon augmentation grafts with use of platelet rich plasma (PRP) in sheep. Methods. A total of 24 sheep were operated on, with the infraspinatus being surgically cut from its attachment to the humeral head. Each tendon was repaired using suture anchors and an interpositional implant according to 4 groups: (1) Empty control, (2) Novel collagen fibre implant with PRP (3) A novel collagen sponge implant (4) and the collagen sponge with PRP. The sheep were killed at 12 weeks and the implant site harvested and its histology evaluated. Results. Our findings showed that these novel grafts were well integrated into the tissue, with minimal inflammatory response. However, as expected, the material had not yet completely broken down. Our initial findings suggest that the combination of PRP with the collagen sponge best enhanced the repair of the tendon. Conclusion. Tissue engineered collagen graft hold great potential for the repair of tendons

Background. Total Shoulder Arthroplasty (TSA) has been shown to improve the function and pain of patients with severe degeneration. Recently, TSA has been of interest for younger patients with higher post-operative expectations; however, they are treated using traditional surgical approaches and techniques, which, although amenable to the elderly population, may not achieve acceptable results with this new demographic. Specifically, to achieve sufficient visualization, traditional TSA uses the highly invasive deltopectoral approach that detaches the subscapularis, which can significantly limit post-operative healing and function. To address these concerns, we have developed a novel surgical approach, and guidance and instrumentation system (for short-stemmed/stemless TSA) that minimize muscle disruption and aim to optimize implantation accuracy. Development. Surgical Approach: A muscle splitting approach with a reduced incision size (∼6–8cm) was developed that markedly reduces muscle disruption, thus potentially improving healing and function. The split was placed between the infraspinatus and teres-minor (Fig.1) as this further reduces damage, provides an obvious dissection plane, and improves access to the retroverted articular surfaces. This approach, however, precludes the use of standard bone preparation methods/instruments that require clear visualization and en-face articular access. Therefore, a novel guidance technique and instrumentation paradigm was developed. Minimally Invasive Surgical Guidance: 3D printed Patient Specific Guides (PSGs) have been developed for TSA; however, these are designed for traditional, highly invasive approaches providing unobstructed access to each articular surface separately. As the proposed approach does not offer this access, a novel PSG with two opposing contoured surfaces has been developed that can be inserted between the humeral and scapular articular surfaces and use the rotator cuff's passive tension to self-locate (Fig.2). During computer-aided pre-operative planning/PSG design, the two bones are placed into an optimized relative pose and the PSG is constructed between and around them. This ensures that when the physical PSG is inserted intra-operatively, the bones are locked into the preoperatively planned pose. New Instrumentation Paradigm: With the constraints of this minimally invasive approach, a new paradigm for bone preparation/instrumentation was required which did not rely on en-face access. This new paradigm involves the ability to simultaneously create glenoid and humeral guide axes – the latter of which can guide humeral bone preparation and be a working channel for tools – by driving a short k-wire into the glenoid by passing through the humerus starting laterally (Fig.3). By preoperatively defining the pose produced by the inserted PSG as one that collinearly aligns the bones’ guide axes, the PSG and an attached c-arm drill guide facilitate this new lateral drilling technique. Subsequently, bone preparation is conducted using novel instruments (e.g. reamers and drills for creating holes radial to driver axis) powered using a trans-humeral driver and guided by the glenoid k-wire or humeral tunnel. Conclusion. To meet the expectations of increasingly younger TSA patients, advancements in procedural invasiveness and implantation accuracy are needed. This need was addressed by developing a novel, fully integrated surgical approach, PSG system, and instrumentation paradigm, the initial in-vitro results of which have demonstrated acceptable accuracy while significantly reducing invasiveness

Background:. Individuals with large Hill-Sachs lesions may be prone to failure and reoccurrence following standard arthroscopic Bankart repair. Here, the Remplissage procedure may promote shoulder stability through infraspinatus capsulo-tenodesis directly into the lesion. Little biomechanicaldata about the Remplissage procedure on glenohumeral kinematics, stability, and range of motion (ROM) currently exists. Questions/purposes:. What are the biomechanical effects of Bankart and Remplissage repair for large Hill-Sachs lesions?. Methods:. Six cadaveric shoulders were tested using a custom shoulder testing system. ROM and glenohumeral translation with applied loads in anterior-posterior (AP) and superior-inferior (SI) directions were quantified at 0° and 60° gleno-humeral abduction. Six conditions were tested: intact, Bankart lesion, Bankart with 40% Hill-Sachs lesion, Bankart repair, Bankart repair with Remplissage, and Remplissage repair alone. Results:. Humeral external rotation (ER) and total range of motion (TR) increased significantly from intact after the creation of the Bankart lesion at both 0° abduction (ER +27.0°, TR +35.8°, p < 0.05) [Fig 1] and 60° abduction (ER +9.5°, TR +30.7°, p < 0.05) [Fig 2], but did not increase further with the addition of the Hill-Sachs lesion. The Bankart repair restored range of motion to intact values 0° abduction at addition of the Remplissage repair did not significantly alter range of motion from the Bankart repair alone. There were no significant changes in AP or SI translation between Bankart repair with and without Remplissage compared to the intact specimen. Conclusions:. The addition of the Remplissage procedure for treatment of large Hill-Sachs lesions had no statistically significant effect on ROM or translation for treatment for large Hill-Sachs lesions. Clinical Relevance: The Remplissage technique may be a suitable option for engaging Hill-Sachs lesions. Further clinical studies are warranted

Purpose. While reverse shoulder arthroplasty (RSA) corrects vertical muscle imbalance, it cannot restore the horizontal imbalance seen in cuff-deficient shoulders with combined loss of active elevation and external rotation (CLEER). We report the medium-term results of the modified latissimus dorsi/teres major tendon transfer (L'Episcopo procedure) associated with RSA, performed via a single deltopectoral approach. Method. Sixteen CLEER patients underwent the procedure and were followed up at a mean of 49 months (range, 36–70). All patients had lost spatial control of their arm, were unable to maintain neutral rotation, and had abnormal infraspinatus and teres minor muscles on imaging. Outcome measures included Constant score (CS), Subjective Shoulder Value (SSV), and ADLER score (activities of daily living requiring external rotation). Results. Fifteen patients were satisfied or very satisfied. There were significant improvements (p<0.05) in active elevation (72 degrees to 139 degrees), active external rotation (−24 degrees to 4 degrees), CS (27 to 64), ADLER score (5.0 to 23.8) and SSV (23% to 77%). Active internal rotation decreased from 6 to 3 points. Scapular notching was observed in 3 patients and spurs in 3 patients. One deep infection required two-stage revision of the prosthesis and the patient was disappointed with the result. One patient required reoperation (arthrolysis and acromioclavicular joint excision). Conclusion. Reverse shoulder arthroplasty combined with the modified L'Episcopo procedure improves shoulder function in patients with CLEER. Patients regain spatial control of their arm. The observed internal rotation loss has led us to modify the surgical technique by fixing the transferred tendons more posteriorly on the humerus

Background:. The purpose of this study was to compare the biomechanical effects of the trapezius transfer and the latissimus dorsi transfer in a cadaveric model of a massive posterosuperior rotator cuff tear. Methods:. Eight cadaveric shoulders were tested at 0°, 30°, and 60° of abduction in the scapular plane with anatomically based muscle loading. Humeral rotational range of motion and the amount of humeral rotation due to muscle loading were measured. Glenohumeral kinematics and joint reaction forces were measured throughout the range of motion. After testing in the intact condition, the supraspinatus and infraspinatus were resected, simulating a massive rotator cuff tear. The lower trapezius transfer was then performed. Three muscle loading conditions for the trapezius (12N, 24N, 36N) were applied to simulate a lengthened graph as a result of excessive creep, a properly tensioned graph exerting a force proportional to the cross-sectional area of the inferior trapezius, and an over-constrained graph respectively. Next the latissimus dorsi transfer was performed and tested with one muscle loading condition 24N. A repeated-measures analysis of variance was used for statistical analysis. Results:. The amount of internal rotation due to muscle loading increased with massive cuff tear at 0°, 30°, 60° abduction (p < 0.05), and was restored with the latissimus transfer at 0° abduction and the trapezius transfer at all abduction angles. (Figure 1) The cuff tear decreased glenohumeral joint compressive force, which was restored with the trapezius transfer at all positions; however, the latissimus transfer failed to restore the intact compressive force (p < 0.05). (Figure 2) At neutral rotation and 0° abduction, there was an increase in the anteriorly directed force for the rotator cuff tear and latissimus transfer conditions, that was restored to intact values by the trapezius transfer (p < 0.05). (Figure 3) At maximum internal rotation and 0° of abduction, the apex of humeral head shifted superiorly and laterally after massive cuff tear (p < 0.05); this abnormal shift was more closely restored to intact values by the trapezius transfer than the latissimus transfer in directions (p < 0.05). Conclusion:. The trapezius transfer for massive cuff tear restores native glenohumeral forces better than the latissimus transfer by recruiting an exogenous force across the glenohumeral joint. However, the increase in compressive force seen with the trapezius transfer may be problematic in patients with osteoarthritis. Clinical studies to evaluate the results of the trapezius transfer are warranted