Chronic Massive Rotator Cuff Tears Research Articles

A composite PET-matrix patch enhances tendon regeneration and tendon-to-bone integration for bridging repair of the chronic massive rotator cuff tears in a rabbit model.

In recent years, bridging repair has emerged as an effective approach for the treatment of massive rotator cuff tears (MRCTs). The objective of this study was to develop a composite patch that combines superior mechanical strength and biocompatibility and evaluate its potential for enhancing the outcomes of bridging repair for MRCTs. The composite patch, referred to as the PET-matrix patch (PM), was fabricated by immersing a plain-woven PET patch in decellularized matrix gel and utilizing the freeze-drying technique. The results demonstrated that the PM has reliable mechanical properties, with a maximum failure load of up to 480 N. The decellularized matrix sponge (DMS), present on the surface of the PM, displayed a loose and porous structure, with an average pore size of 62.51 μm and a porosity of 95.43%. In vitro experiments showed significant elongation of tenocytes on the DMS, with cells spanning across multiple pores and extending multiple protrusions as observed on SEM images. In contrast, tenocytes on the PET patch appeared smaller in size and lacked significant elongation. Additionally, the DMS facilitated the proliferation, migration and differentiation of tenocytes. In a rabbit model of chronic MRCTs, the PM group showed superior outcomes compared to the PET group at 4, 8 and 12 weeks after bridging repair. The PM group displayed significantly higher tendon maturing score, larger collagen diameter in the regenerated tendon and improved tendon-to-bone healing scores compared to the PET group (P < 0.05). Moreover, the maximum failure load of the tendon-bone complex in the PM group was significantly higher than that in the PET group (P < 0.05). In summary, the PM possesses reliable mechanical properties and excellent cytocompatibility, which can significantly improve the outcomes of bridging repair for chronic MRCTs in rabbits. Therefore, it holds great potential for clinical applications.

Efficacy of a Novel Electroconductive Matrix To Treat Muscle Atrophy and Fat Accumulation in Chronic Massive Rotator Cuff Tears of the Shoulder.

The high retear rate after a successful repair of the rotator cuff (RC) is a major clinical challenge. Muscle atrophy and fat accumulation of RC muscles over time adversely affect the rate of retear. Since current surgical techniques do not improve muscle degenerative conditions, new treatments are being developed to reduce muscle atrophy and fat accumulation. In the previous study, we have shown the efficacy of aligned electroconductive nanofibrous fabricated by coating poly(3,4-ethylene dioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) nanoparticles onto aligned poly(ε-caprolactone) (PCL) electrospun nanofibers (PEDOT:PSS matrix) to reduce muscle atrophy in acute and subacute models of RC tears (RCTs). In this study, we further evaluated the efficacy of the PEDOT:PSS matrix to reduce muscle atrophy and fat accumulation in a rat model of chronic massive full-thickness RCTs (MRCTs). The matrices were transplanted on the myotendinous junction to the belly of the supraspinatus and infraspinatus muscles at 16 weeks after MRCTs. The biomechanics and histological assessments showed the potential of the PEDOT:PSS matrix to suppress the progression of muscle atrophy, fat accumulation, and fibrosis in both supraspinatus and infraspinatus muscles at 24 and 32 weeks after MRCTs. We also demonstrated that the PEDOT:PSS matrix implantation significantly improved the tendon morphology and tensile properties compared with current surgical techniques.

Peculiarities of Acromioplasty in Patients with Chronic Massive Rotator Cuff Ruptures

Background. According to the literature, from 14% to 28% of patients with rotator cuff tendon ruptures have unsatisfactory results of treatment and require a reverse shoulder joint arthroplasty in the future.&#x0D; Objective: to compare the results of open rotator cuff repair of chronic massive rotator cuff tears in groups with standard subacromial decompression and subacromial decompression with resection of the lateral part of the acromion.&#x0D; Materials and Methods. The study included 58 patients who underwent an open rotator cuff repair of chronic massive rotator cuff tears (supraspinatus and infraspinatus tendons) and who underwent a rehabilitation program and follow-up up to 12 months after surgery. The age of the patients ranged from 30 to 60 years. All patients were divided into 2 groups: group 1 – classic subacromial decompression, group 2 – classic subacromial decompression complemented by resection of 5 mm of the lateral end of the acromion. Shoulder joint function was assessed using the Constant Shoulder Score and VAS scales before surgery, 6 and 12 months after surgery.&#x0D; Results. Six months after surgery, the mean functional result on the Constant Shoulder Score scale in group 1 was slightly worse (24.5 ± 16.2 points) than in group 2 (18.5 ± 6.1 points); p = 0.131. Twelve months after surgery, the mean functional score on the Constant Shoulder Score was 21.1 ± 5.6 points in group 1 and 10.1 ± 6.1 points in group 2 (p = 0.031). Six months after surgery, the average score on the VAS scale was worse in group 1 than in group 2 and ranged from 3.5 ± 1.2 points. Twelve months after surgery, the mean score on the VAS scale was also worse in group 1 than in group 2 (p = 0.05). Conclusions. Resection of the lateral part of the acromion during the open rotator cuff repair of chronic massive rotator cuff tendons tears allows to obtain better average functional results of treatment both 6 months and 12 months after the surgery. Resection of the lateral end of the acromion changes the vector of the total force of the rotator cuff and deltoid muscles during shoulder elevation. This reduces the probability of the subacromial conflict syndrome development and thus reduces the load on the area of the rotator cuff tendon suture.

Electroconductivity, a regenerative engineering approach to reverse rotator cuff muscle degeneration.

Muscle degeneration is one the main factors that lead to the high rate of retear after a successful repair of rotator cuff (RC) tears. The current surgical practices have failed to treat patients with chronic massive rotator cuff tears (RCTs). Therefore, regenerative engineering approaches are being studied to address the challenges. Recent studies showed the promising outcomes of electroactive materials (EAMs) on the regeneration of electrically excitable tissues such as skeletal muscle. Here, we review the most important biological mechanism of RC muscle degeneration. Further, the review covers the recent studies on EAMs for muscle regeneration including RC muscle. Finally, we will discuss the future direction toward the application of EAMs for the augmentation of RCTs.

RTSA With Humeral Head Autograft Glenoid Reconstruction

Background: Untreated chronic massive rotator cuff tears and primary osteoarthritis can lead to conditions of significant retroversion, posterior bone loss, and humeral head subluxation. Indications: Reverse total shoulder arthroplasty with humeral head autograft glenoid reconstruction may be indicated in patients with advanced glenohumeral osteoarthritis and/or severe glenoid retroversion/bone loss due to rotator cuff arthropathy, trauma, primary, or inflammatory osteoarthritis. Technique: Besides routine radiography and preoperative computed tomography (CT) scans, 3-dimensional (3D) planning software is often performed as a routine part of preoperative planning. A 3D printed model of the glenoid can also be helpful in cases of significant bone deformity. Patients are placed in a 45° modified beach chair position. Using a standard deltopectoral approach, the glenoid is exposed. An anatomic humeral head resection is made. The contour of the articular margin of the humeral head should match the glenoid bone deficiency anatomically as it has been chronically resting within the glenoid defect. Three dimensional preoperative planning and the 3D printed model are used to make an asymmetric humeral head autograft which should match the deficiency perfectly. The articular cartilage is removed with a burr. The graft and baseplate are coupled together (metaphyseal bone facing the baseplate and prepared articular side of the graft facing native bone) and measurements are performed with the preoperative planning software to fashion a graft with the appropriate dimension and with the desired amount of lateralization. The bone graft is then compressed with the baseplate to the native glenoid and fixed with screws. Results: In select patients with careful preoperative planning, excellent outcomes can be achieved with careful gradual resumption of range of motion and strength with physical therapy. Sequential radiographic imaging is performed up to 6 months and beyond to confirm solid union of graft to native glenoid bone and incorporation into the baseplate. Discussion/Conclusion: Reverse total shoulder arthroplasty (rTSA) with humeral head autograft glenoid reconstruction is an excellent option to address severe glenoid bone loss and restore the native joint line for both primary osteoarthritis and rotator cuff arthropathy. Using 3D CT scans, 3D preoperative planning software and 3D printing of the glenoid can help achieve a good outcome. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

The Arthroscopic Trillat Procedure Is a Valuable and Durable Treatment Option for Recurrent Anterior Instability Associated With Massive Irreparable Cuff Tears

The purpose of the present study is to report the mid- and long-term clinical and radiologic outcomes of the arthroscopic Trillat for the treatment of recurrent anterior instability in patients with chronic massive irreparable rotator cuff tears (MIRCTs) and maintained active shoulder motion where reverse shoulder arthroplasty (RSA) is not indicated. Twenty-one consecutive patients (mean age 61 years) were identified and retrospectively reviewed. All patients had recurrent anterior dislocations and conserved active forward elevation and active external rotation. The MIRCTs included a retracted (stage 3) supraspinatus tear in 14%, a supra- and infraspinatus tear in 76.5%, and a 3-tendon tear in 14%. A closed-wedge osteotomy of the coracoid was performed, and the coracoid was fixed above the subscapularis with a cannulated screw (10 cases) or suture buttons (11 cases). We followed patients with x-rays and computed tomography scan at 6 months, along with Subjective Shoulder Value, visual analog scale, Walch, Constant, and Rowe scores. The mean clinical and radiographic follow-up was 58 months (24-145 months). Overall, 96% (20/21) of the patients had a stable and functional shoulder and were satisfied with the procedure; no patient lost active shoulder motion. The Subjective Shoulder Value increased from 44% (10%-75%) to 94% (80%-100%), P < .001. The Constant and Rowe scores improved from 60 (25-81) to 81 (66-96) and from 54 (35 to 65) to 92 (70-100), respectively (P < .001). Among the 13 patients practicing sports before surgery, 10 (77%) went back to sports. At last follow-up, only 1 patient was revised to RSA. The arthroscopic Trillat procedure is a valuable and durable option for the treatment of recurrent anterior dislocations in older patients with chronic MIRCTs and conserved active shoulder motion. Level IV, therapeutic case series.

Risk factors of radiographic severity of massive rotator cuff tear

As massive rotator cuff tears progress, various radiographic changes occur; however, the factors associated with radiographic changes remain largely unknown. This study aimed to determine the factors that affect radiographic severity in massive rotator cuff tears using multivariate analyses. We retrospectively reviewed 210 shoulders with chronic massive rotator cuff tears. The dependent variables were superior migration of the humeral head (Hamada grades 2–3), narrowing of the glenohumeral joint (grade 4), and humeral head collapse (grade 5). Baseline variables that were significant in univariate analyses were included in multivariate models. There were 91, 59, 43, and 17 shoulders classified as Hamada grades 1, 2–3, 4, and 5, respectively. Multivariate analysis showed that infraspinatus tear (P = 0.015) and long head of biceps (LHB) tendon rupture (P = 0.007) were associated with superior migration of humeral head. Superior subscapularis tear (P = 0.003) and LHB tendon rupture (P < 0.001) were associated with narrowing of glenohumeral joint. Female sex (P = 0.006) and superior subscapularis tear (P = 0.006) were associated with humeral head collapse. This study identified the rupture of infraspinatus and LHB as risk factors of superior migration of humeral head, and the rupture of subscapularis and LHB and female sex as risk factors of cuff tear arthropathy.

Muscle degeneration in chronic massive rotator cuff tears of the shoulder: Addressing the real problem using a graphene matrix

Massive rotator cuff tears (MRCTs) of the shoulder cause disability and pain among the adult population. In chronic injuries, the tendon retraction and subsequently the loss of mechanical load lead to muscle atrophy, fat accumulation, and fibrosis formation over time. The intrinsic repair mechanism of muscle and the successful repair of the torn tendon cannot reverse the muscle degeneration following MRCTs. To address these limitations, we developed an electroconductive matrix by incorporating graphene nanoplatelets (GnPs) into aligned poly(l-lactic acid) (PLLA) nanofibers. This study aimed to understand 1) the effects of GnP matrices on muscle regeneration and inhibition of fat formation invitro and 2) the ability of GnP matrices to reverse muscle degenerative changes invivo following an MRCT. The GnP matrix significantly increased myotube formation, which can be attributed to enhanced intracellular calcium ions in myoblasts. Moreover, the GnP matrix suppressed adipogenesis in adipose-derived stem cells. These results supported the clinical effects of the GnP matrix on reducing fat accumulation and muscle atrophy. The histological evaluation showed the potential of the GnP matrix to reverse muscle atrophy, fat accumulation, and fibrosis in both supraspinatus and infraspinatus muscles at 24 and 32 wk after the chronic MRCTs of the rat shoulder. The pathological evaluation of internal organs confirmed the long-term biocompatibility of the GnP matrix. We found that reversing muscle degenerative changes improved the morphology and tensile properties of the tendon compared with current surgical techniques. The long-term biocompatibility and the ability of the GnP matrix to treat muscle degeneration are promising for the realization of MRCT healing and regeneration.

Biomechanical and Histological Results of Dual-Suspensory Reconstruction Using Banded Tendon Graft to Bridge Massive Rotator Cuff Tears in a Chronic Rabbit Model

Background: Bridging rotator cuff tendon defects with a patch is a reasonable treatment for massive rotator cuff tears (MRCTs). However, the poor outcomes associated with routine patch repair have prompted exploration into superior bridging techniques and graft structures. Purpose: To detect whether dual-suspensory reconstruction using a banded graft would be superior to routine bridging using a patch graft to treat MRCTs and to detect the comparative effectiveness of patellar tendon (PT) and fascia lata (FL) grafts in dual-suspensory reconstruction. Study Design: Controlled laboratory study. Methods: Unilateral chronic MRCTs were created in 72 mature male New Zealand White rabbits, which were randomly divided into 3 groups: (1) patch bridging repair using rectangular FL autograft (PR-FL), (2) dual-suspensory bridging reconstruction using banded FL autograft (DSR-FL), and (3) dual-suspensory bridging reconstruction using banded PT autograft (DSR-PT). In each group, the mean failure load and stiffness of the cuff-graft-humerus (C-G-H) complexes of 6-week and 12-week specimens were recorded, with the failure modes and sites noted. Moreover, cuff-to-graft and graft-to-bone interface healing and graft substance remodeling of the complexes were histologically evaluated (via hematoxylin and eosin, Picrosirius red, Masson trichrome, and Safranin O/fast green staining) at 6 and 12 weeks to assess integrations between the bridging constructs and the native bone or rotator cuff tendons. Results: The DSR-PT group had the greatest mean failure loads and stiffness of the C-G-H complexes at 6 and 12 weeks (41.81 ± 7.00 N, 10.34 ± 2.68 N/mm; 87.62 ± 9.20 N, 17.98 ± 1.57 N/mm, respectively), followed by the DSR-FL group (32.04 ± 5.49 N, 8.20 ± 2.27 N/mm; 75.30 ± 7.31 N, 14.39 ± 3.29 N/mm, respectively). In the DSR-PT and DSR-FL groups, fewer specimens failed at the graft-to-bone junction and more failed at the cuff-to-graft junction, but both groups had higher median failure loads at 6 and 12 weeks (DSR-PT: cuff-to-graft junction, 37.80 and 83.76 N; graft-to-bone junction, 45.46 and 95.86 N) (DSR-FL: cuff-to-graft junction, 28.52 and 67.68 N; graft-to-bone junction, 37.92 and 82.18 N) compared with PR-FL (cuff-to-graft junction, 27.17 and 60.04 N; graft-to-bone junction, 30.12 and 55.95 N). At 12 weeks, the DSR-FL group had higher median failure loads at graft substance (72.26 N) than the PR-FL group (61.27 N). Moreover, the PR-FL group showed more inflammatory responses at the 2 healing interfaces and the graft substance in the 6-week specimens and subsequently displayed poorer interface healing (assessed via collagen organization, collagen maturity, and fibrocartilage regeneration) and graft substance remodeling (assessed via collagen organization and maturity) in 12-week specimens compared with the DSR-PT and DSR-FL groups. Superior interface healing and substance remodeling processes were observed in the DSR-PT group compared with the DSR-FL group. Conclusion: When compared with routine patch repair, the dual-suspensory reconstructions optimized biomechanical properties and improved interface healing and graft substance remodeling for bridging MRCTs. Furthermore, the dual-suspensory technique using the PT graft presented superior histological and biomechanical characteristics than that using FL. Clinical Relevance: The dual-suspensory reconstruction technique using banded tendon grafts may enhance bridging constructs for MRCTs in humans, warranting further investigations of clinical outcomes.

Risk Factors for Loss of Active Shoulder Range of Motion in Massive Rotator Cuff Tears.

Background:Patients with massive rotator cuff tears often exhibit loss of active range of shoulder motion, which can interfere with activities of daily living. The risk factors for loss of motion remain largely unknown.Purpose:To clarify the predictive factors that affect the range of motion in chronic massive rotator cuff tears using multivariate analyses.Study Design:Case-control study; Level of evidence, 3.Methods:The authors retrospectively reviewed 204 consecutive patients who were evaluated at their institution with chronic massive rotator cuff tears. In this study, the dependent variable was determined to be active anterior elevation limited to ≤90° or external rotation (ER) with the arm at the side limited to ≤0°. Explanatory variables included age; sex; affected side; duration of symptoms; smoking history; existence of diabetes, hypertension, or rheumatoid arthritis; involved tendons; presence of a 3-tendon tear; rupture of the long head of biceps tendon; superior migration of the humeral head; and cuff tear arthropathy. Baseline variables that were observed to be significant in the univariate analyses were included in multivariate models, which used logistic regression to identify independent predictors of loss of motion.Results:Overall, 73 patients (35.8%) exhibited limited anterior elevation, and 27 (13.2%) exhibited limited ER. Multivariate analyses showed that inferior subscapularis tear (odds ratio [OR], 14.66; 95% CI, 2.95-72.93; P = .001), smoking (OR, 4.13; 95% CI, 1.94-8.79; P < .001), superior migration of humeral head (OR, 3.92; 95% CI, 1.80-8.53; P = .001), and 3-tendon tear (OR, 3.29; 95% CI, 1.32-8.20; P = .011) were significantly associated with the loss of anterior elevation. Teres minor tear (OR, 73.37; 95% CI, 9.54-564.28; P < .001) and superior migration of the humeral head (OR, 3.55; 95% CI, 1.04-12.19; P = .044) were significantly associated with loss of ER.Conclusion:In the current study, a history of smoking, type of torn tendons, and superior migration of the humeral head were associated with loss of active shoulder motion. In particular, the status of inferior subscapularis or teres minor contributed to the onset of pseudoparalysis in massive rotator cuff tears.

The Regenerative Role of Gelatin in PLLA Electrospun Membranes for the Treatment of Chronic Massive Rotator Cuff Injuries.

Failing to regenerate native tendon tissue in chronic massive rotator cuff tears (CMRCTs) results in high retear rates after surgery. Gelatin is a hydrolyzed form of collagen which is bioactive and biocompatible. This study intends to investigate the suitability of integrating gelatin to poly (l-lactic acid) (PLLA) fibrous membranes for promoting the healing of CMRCTs. PLLA/Gelatin electrospun membranes (PGEM) are fabricated using electrospinning technology. The fourier transform infrared, static contact angles are tested sequentially. Cytocompatibility is evaluated with rat tendon fibroblasts and human umbilical endothelial cells (HUEVCs) lines. CMRCTs rat models are established and assigned into three groups (the sham group, the repaired group, and the augmentation group) to perform histomorphological and biomechanical evaluations. Gelatin is successfully integrated into PLLA fibrous membranes by the electrospinning technique. In vitro studies indicate that PGEM shows a great cytocompatibility for rat tendon fibroblasts and HUEVCs. In vivo studies find that applications of PGEM significantly promote well-aligned collagen I fibers formation and enhance biomechanical properties of the repaired tendon in CMRCTs rat models. In summary, gelatin promotes tendon fibroblasts and HUEVCs adhesion, migration, and proliferation on the PLLA fibrous membranes, and PGEM may provide a great prospect for clinical application.

Chronic Pseudoparalysis Needs to Be Distinguished From Pseudoparesis: A Structural and Biomechanical Analysis

Background: Chronic pseudoparalysis is generally defined as the inability to actively elevate the arm above 90° with free passive range of motion and no neurological deficits. It has been suggested that this arbitrary cutoff needs to be refined. Purpose: To analyze whether there are structural and biomechanical differences in patients with chronic pseudoparalysis and those with chronic pseudoparesis. Study Design: Case-control study; Level of evidence, 3. Methods: In this retrospective study, 50 patients with chronic massive rotator cuff tears (mRCTs; ≥2 tendons) and free passive and active scapular plane abduction <90° were divided into 2 groups: pseudoparalysis group (n = 24; active scapular plane abduction, <45°) and pseudoparesis group (n = 26; active scapular plane abduction, >45° and <90°). Radiographic measurements included the critical shoulder angle, acromiohumeral distance, posterior acromial tilt, anterior and posterior acromial coverages, and posterior acromial height on outlet views. Measurements on magnetic resonance imaging (MRI) included fatty infiltration of the rotator cuff muscles, anterior (subscapularis) and posterior (infraspinatus/teres minor) tear extensions, and global (anterior + posterior) tear extension in the parasagittal plane. A published musculoskeletal model was used to simulate the effect of different mRCTs on the muscle force required for scapular plane abduction. Results: Plain radiographs revealed no differences between patients with chronic pseudoparalysis and those with pseudoparesis. MRI assessment showed significant differences between patients with chronic pseudoparalysis and those with pseudoparesis with respect to fatty infiltration of the subscapularis (2.9 vs 1.6; P < .001) and infraspinatus (3.6 vs 3.0; P < .001) muscles, and anterior (−23° vs 4°; P < .001), posterior (−23° vs −14°; P = .034), and global rotator cuff (225° vs 190°; P < .001) tear extensions. The anterior tear extension in patients with chronic pseudoparalysis always involved more than 50% of the subscapularis, which was associated with an odds ratio of 5 for inability to actively abduct more than 45°. The biomechanical model was unable to find a combination of muscles that could balance the arm in space when the tear extended beyond the supraspinatus and the cranial subscapularis. Conclusion: This study confirms that chronic pseudoparalysis and pseudoparesis are associated with different structural lesions. In the setting of a chronic mRCT, involvement of more than 50% of the subscapularis tendon with fatty infiltration of stage 3 is associated with pseudoparalysis of active scapular plane abduction <45°. The key function of the subscapularis was confirmed in the biomechanical model.

Primary arthroscopic repair of massive rotator cuff tears results in significant improvements with low rate of re-tear.

To conduct a systematic review of outcomes following primary arthroscopic repair of chronic massive rotator cuff tears (RCTs) and to assess clinical outcomes and rates of repair failure. The authors' preferred treatment algorithm is also provided. Medline, Embase and PubMed were searched identifying articles pertaining to primary arthroscopic repair of chronic massive RCTs without the use of augmentation. Primary outcomes were patient-reported outcomes and the secondary outcome was the rate of repair failure. Outcome data were pooled and presented as well as assessment of study methodological quality. Data from studies reporting similar outcome measures were pooled when possible, and mean differences alongside confidence intervals and p values were reported, where appropriate. Twenty-six studies (1405 participants) were included, with mean age of 62years (range 52-69). The mean duration of symptoms pre-operatively was 31months (range 6-40), and the mean follow-up time was 39months (range 12-111). Complete repair was performed in 78% of patients and partial repair was performed in 22%. Both complete and partial repairs resulted in significant improvements with respect to pain, range of motion and functional outcome scores. The rate of repair failure for the total cohort was 36% at a mean follow-up of 31months, and for the complete and partial repair subgroups the failure rate was 35% and 40%, respectively. Arthroscopic repairs of chronic, massive RCTs, whether complete or partial, are associated with significant improvements in pain, function and objective outcome scores. The rate of repair failure is lower than previously reported, however, still high at 36%. The present paper finds that arthroscopic repair is still a viable treatment option for massive RCTs. IV.

Bone density in massive rotator cuff tears and possible implications in superior capsular reconstruction

Superior capsular reconstruction (SCR) by using either the fascia lata autograft or a dermal allograft patch are newly described solutions that could prevent superior humeral head migration and restore the anteroposterior shoulder muscle force couple. However, despite initially promising clinical and radiographic outcomes, the more recent literature shows disparity in the results. Possible predisposing factors for SCR structural failure is poor bone quality in the humeral and glenoid fixation points. The purpose of this study was to assess bone density at these points using computed tomography. We retrospectively assessed the CT-scans of 26 patients with chronic massive rotator cuff tears (MRCTs). We used the CT-scans of 10 patients without rotator cuff pathology, arthritis or fractures as a control group. Using Horos software, we performed 3D-multiplanar reconstruction of the images and we established the possible anchor placements on the glenoid and humerus. Therefore, we recognized two fixation points on the glenoid (anterior and posterior), approximately 5 mm medial to the articular surface. Respectively we established four fixation points on the humerus, two medially at the limit of the articular surface (anteriorly in the bicipital groove and posteriorly at the level of the infraspinatus) and two laterally (at the same level with medial points in the coronal plane and 1 cm lateraly in the axial plane). The Hounsfield units (HU) were measured at these points. Healthy control patients at the selected glenoid fixation points one density in HU of 235 ± 53 anteriorly and 287 ± 98 posteriorly. The respective values in patients with MRCTs were 125 ± 36 and142 ± 42, and the differences were statistically significant (p > 0.001 and p = 0.001). Medial humeral fixation points in HU were 115 ± 33 anteriorly and 178 ± 58 posteriorly in healthy patients. The respective values in MRCTs were 78 ± 40 and 77 ± 38 (p = 0.034 and p > 0.001). Finally, for the lateral humeral fixation points in the control group, the HU were 111 ± 22 anteriorly and 130 ± 45 posteriorly. In patients with MRCTs the respective values were 68 ± 40 and 69 ± 41 (p = 0.006 and p = 0.002). Assessment with computer tomography shows that bone density is severely affected in patients with MRCTs, compared to healthy controls. Additionally, the glenoid and the posterior humerus seem to be the weakest fixation points for SCR with 50 % less bone density.

The Role of Partial Rotator Cuff Repairs in Patients With Massive Irreparable Tears Without Arthritis.

In patients with chronic massive rotator cuff tears, complete repair is often not achievable or the repair is performed under significant tension with risk of early failure. The goal of a partial rotator cuff repair is to decrease pain, restore force couples, and improve range of motion of the shoulder. A systematic review was performed to assess active range of motion (ie, forward elevation, external rotation), pain, and patient-reported outcome scores after partial repair of massive rotator cuff tears. Significant improvements in forward elevation, visual analog scale pain scores, American Shoulder and Elbow Surgeons scores, and Constant scores were observed, and perioperative complication rates were minimal. Partial rotator cuff repairs remain a viable treatment option in this patient population. [Orthopedics. 2020; 43(1):e1-e7.].

Advance of massive tear of the rotator cuff treated with a deltoid flap

Massive rotator cuff tears often destroy equilibrium of couples of the shoulder joints, whichlead toshoulder pain and functional incapacitation. At present, there is a great controversy about the best treatment strategy for the massive rotator cuff tear, nevertheless surgery has been proved to have more satisfactory results than non-operative treatment. It has been confirmed by numerous studies that cuff repair could prevent loss of shoulder strength and glenohumeral osteoarthritis. However, it is impossible to suture tendon to bone directly due to retraction of tendon stump, fat infiltration of rotator cuff and prominent tear size in massive rotator cuff tear. Muscular flap transfer procedures have played important roles in the treatment of massive rotator cuff tears. Compared with other tendon transposition procedures, such as latissimus dorsi transfer, the deltoid muscular flap may be an optimal method as it works synergistically with the infraspinatus and supraspinatus muscle, and presses down the humeral head potentially. Cuff repair in open operation with tendon stump re-attachment to the deltoid muscle flap, aims to reconstruct the cuff continuity and cover the humeral head toform a new cuff. The deltoid muscle flap, also acting as a muscle cushion, is expected to reduce impingement between the humeral head and the acromion and get better results of pain relief and improvement of shoulder function. However, it is still controversial about the efficacy of deltoid muscle flap transfer in reconstructing a new balance of couple with better shoulder strength, alleviating glenohumeral arthritis and preventing tendon retears. This article reviews the advances in the treatment of chronic massive rotator cuff tears with deltoid flap transfer.

The effect of adipose-derived stem cells on enthesis healing after repair of acute and chronic massive rotator cuff tears in rats

Chronic massive rotator cuff tears heal poorly and often retear. This study investigated the effect of adipose-derived stem cells (ADSCs) and transforming growth factor-β3 (TGF-β3) delivered in 1 of 2 hydrogels (fibrin or gelatin methacrylate [GelMA]) on enthesis healing after repair of acute or chronic massive rotator cuff tears in rats. Adult male Lewis rats underwent bilateral transection of the supraspinatus and infraspinatus tendons with intramuscular injection of botulinum toxin A (n = 48 rats). After 8 weeks, animals received 1 of 8 interventions (n = 12 shoulders/group): (1) no repair, (2) repair only, or repair augmented with (3) fibrin, (4) GelMA, (5) fibrin + ADSCs, (6) GelMA + ADSCs, (7) fibrin + ADSCs + TGF-β3, or (8) GelMA + ADSCs + TGF-β3. An equal number of animals underwent acute tendon transection and immediate application of 1 of 8 interventions. Enthesis healing was evaluated 4 weeks after the repair by microcomputed tomography, histology, and mechanical testing. Increased bone loss and reduced structural properties were seen in chronic compared with acute tears. Bone mineral density of the proximal humerus was higher in repairs of chronic tears augmented with fibrin + ADSCs and GelMA + ADSCs than in unrepaired chronic tears. Similar improvement was not seen in acute tears. No intervention enhanced histologic appearance or structural properties in acute or chronic tears. Surgical repair augmented with ADSCs may provide more benefit in chronic tears compared with acute tears, although there was no added benefit to supplementing ADSCs with TGF-β3.

Outcomes of arthroscopic rotator cuff repair with muscle advancement for massive rotator cuff tears

We performed arthroscopic rotator cuff repair (ARCR) combined with miniopen supraspinatus and infraspinatus muscle advancement for massive rotator cuff tears (RCTs) to decrease tension at the repair site with the goal of reduction of the failure rate. We evaluated the clinical outcomes and failure rate after this procedure. This study included 47 patients diagnosed with chronic massive RCTs between October 2010 and March 2015. Of these patients, 21 underwent transosseous equivalent (TOE) ARCR only (control group), and 26 underwent TOE ARCR with muscle advancement (study group). We evaluated shoulder clinical outcomes at preoperative and postoperative assessments and also measured muscle strength and the acromiohumeral interval (AHI) at the same time in both groups. Failure rates were calculated in both groups by evaluating the cuff integrity with postoperative magnetic resonance imaging. Although there was statistically significant improvement for the mean clinical scores in the both groups, there were no significant differences between the 2 groups. The postoperative abduction muscle strength and AHI were significantly higher in the study group (46.3 ± 20.6 N and 9.4 ± 2.9 mm; P = .04) than in the control group (34.6 ± 20.0 N and 7.7 ± 3.0 mm; P = .04). The failure rates were significantly lower in the study group than in the control group (23.1% and 52.4%; P = .03). The TOE ARCR with muscle advancement can achieve significantly better abduction muscle strength, wider AHI, and lower failure rates for massive RCTs than the normal TOE ARCR.

Biceps Detachment Preserves Joint Function in a Chronic Massive Rotator Cuff Tear Rat Model

Background: Lesions of the long head of the biceps tendon are often associated with massive rotator cuff tears (MRCTs), and biceps tenotomy is frequently performed for pain relief and functional reservation. However, the efficacy and safety of biceps tenotomy regarding the effects on the surrounding tissues in chronic MRCT are unclear. Hypothesis: Biceps tenotomy would result in improved mechanical and histological properties of the intact subscapularis tendon and improved in vivo shoulder function while not compromising glenoid cartilage properties. Study Design: Controlled laboratory study. Methods: Right supraspinatus and infraspinatus tendons were detached in 25 male Sprague-Dawley rats, followed by 4 weeks of cage activity to create a chronic MRCT condition. Animals were randomly divided into 2 groups and received either biceps tenotomy (n = 11) or sham surgery (n = 14) and were sacrificed 4 weeks thereafter. Forelimb gait and ground-reaction forces were recorded 1 day before the tendon detachment (baseline), 1 day before the surgical intervention (biceps tenotomy or sham), and 3, 7, 10, 14, 21, and 28 days after the intervention to assess in vivo shoulder joint function. The subscapularis tendon and glenoid cartilage were randomly allocated for mechanical testing or histologic assessment after the sacrifice. Results: Compared with sham surgery, biceps tenotomy partially restored the in vivo shoulder joint function, with several gait and ground-reaction force parameters returning closer to preinjury baseline values at 4 weeks. With biceps tenotomy, mechanical properties of the subscapularis tendons were improved, while mechanical properties and histological Mankin scores of the glenoid cartilage were not diminished when compared with the sham group. Conclusion: Biceps tenotomy in the presence of chronic MRCT partially preserves overall shoulder function and potentially restores subscapularis tendon health without causing detrimental effects to joint cartilage. This laboratory study adds to the growing literature regarding the protective effects of biceps tenotomy on the shoulder joint in a chronic MRCT model. Clinical Relevance: This study provides important basic science evidence supporting the use of biceps tenotomy in patients with massive rotator cuff tears.

Mesenchymal Stem Cell Secretome Improves Tendon Cell Viability In Vitro and Tendon-Bone Healing In Vivo When a Tissue Engineering Strategy Is Used in a Rat Model of Chronic Massive Rotator Cuff Tear

Background: Massive rotator cuff tears (MRCTs) represent a major clinical concern, especially when degeneration and chronicity are involved, which highly compromise healing capacity. Purpose: To study the effect of the secretome of mesenchymal stem cells (MSCs) on tendon cells (TCs) followed by the combination of these activated TCs with an electrospun keratin-based scaffold to develop a tissue engineering strategy to improve tendon-bone interface (TBi) healing in a chronic MRCT rat model. Study Design: Controlled laboratory study. Methods: Human TCs (hTCs) cultured with the human MSCs (hMSCs) secretome (as conditioned media [CM]) were combined with keratin electrospun scaffolds and further implanted in a chronic MRCT rat model. Wistar-Han rats (N = 15) were randomly assigned to 1 of 3 groups: untreated lesion (MRCT group, n = 5), lesion treated with a scaffold only (scaffold-only group, n = 5), and lesion treated with a scaffold seeded with hTCs preconditioned with hMSCs-CM (STC_hMSC_CM group, n = 5). After sacrifice, 16 weeks after surgery, the rotator cuff TBi was harvested for histological analysis and biomechanical testing. Results: The hMSCs secretome increased hTCs viability and density in vitro. In vivo, a significant improvement of the tendon maturing score was observed in the STC_hMSC_CM group (mean ± standard error of the mean, 15.6 ± 1.08) compared with the MRCT group (11.0 ± 1.38; P < .05). Biomechanical tests revealed a significant increase in the total elongation to rupture (STC_hMSC_CM, 11.99 ± 3.30 mm; scaffold-only, 9.89 ± 3.47 mm; MRCT, 5.86 ± 3.16 mm; P < .05) as well as a lower stiffness (STC_hMSC_CM, 6.25 ± 1.74 N/mm; scaffold-only, 6.72 ± 1.28 N/mm; MRCT, 11.54 ± 2.99 N/mm; P < .01). Conclusion: The results demonstrated that hMSCs-CM increased hTCs viability and density in vitro. Clear benefits also were observed when these primed cells were integrated into a tissue engineering strategy with an electrospun keratin scaffold, as evidenced by improved histological and biomechanical properties for the STC_hMSC_CM group compared with the MRCT group. Clinical Relevance: This work supports further investigation into the use of MSC secretome for priming TCs toward a more differentiated phenotype, and it promotes the tissue engineering strategy as a promising modality to help improve treatment outcomes for chronic MRCTs.