Rotator Cuff Tendon Injuries Research Articles

Comparative Analysis of Mini Open versus Arthroscopic Repair of Supraspinatus Tears

Background and Aim: Among all the rotator cuff tendon injuries, supraspinatus tear is very common and it is mostcommon in older individuals. Before the arthroscopy came into high demand, the open repair of supraspinatustear was the preferred method of surgery. Recently, the miniopen technique of repair has also gained popularitybecause of certain factors like better repair strength, requires less expertise and facilitates early active mobilization.Present stud was performed to compare functional and clinical outcomes of arthroscopic and mini-open repair.Material and Methods: The present analysis is the randomized control study done on the patients diagnosedwith rotator cuff tears and was planned with supraspinatus repair with the use of arthroscopic and mini opentechnique. As per the inclusion and exclusion criteria total of 128 patients were included in the study. The includedpatients were equally divided into two groups: 64 patients who underwent mini-open repair and 64 patientswho underwent arthroscopic repair. Follow up was done after 12 months postoperatively and the results wereevaluated using University of California Los Angeles (UCLA) shoulder score.Results: For arthroscopic repair group, UCLA shoulder score were: 26 patients got excellent result, 30 patients gotgood result and only 8 patients got fair result. In the other group UCLA shoulder score were: 22 patients in whomexcellent results were obtained good results were obtained in 32 patients and in 10 patients we got fair results.Conclusion: The arthroscopic procedure decreased postoperative pain, faster regains normal ROM and quickerreturn to function and in turn early return to work compared to mini-open procedure. The arthroscopic procedurebetter in addressing intra-articular and other associated problems than mini-open technique.

Understanding Fibrous Tissue in the Effective Healing of Rotator Cuff Injury.

The rotator cuff is a crucial group of muscles and tendons in the shoulder complex that plays a significant role in the stabilization of the glenohumeral joint and enabling a wide range of motion. Rotator cuff tendon tears can occur due to sudden injuries or degenerative processes that develop gradually over time, whether they are partial or full thickness. These injuries are common causes of shoulder pain and functional impairment, and their complex nature highlights the essential role of the rotator cuff in shoulder function. Scar formation is a crucial aspect of the healing process initiated following a rotator cuff tendon tear, but excessive fibrous tissue development can potentially lead to stiffness, discomfort, and movement limitations. Age is a critical risk factor, with the prevalence of these tears increasing among older individuals. This comprehensive review aims to delve deeper into the anatomy and injury mechanisms of the rotator cuff. Furthermore, it will inspect the signaling pathways involved in fibrous tissue development, evaluate the various factors affecting the healing environment, and discuss proactive measures aimed at reducing excessive fibrous tissue formation. Lastly, this review identifed gaps within existing knowledge to advance methods for better management of rotator cuff tendon injuries.

Bone Marrow Mobilization and Local Stromal Cell-Derived Factor-1α Delivery Enhances Nascent Supraspinatus Muscle Fiber Growth.

Rotator cuff tear is a significant problem that leads to poor clinical outcomes due to muscle degeneration after injury. The objective of this study was to synergistically increase the number of proregenerative cells recruited to injure rotator cuff muscle through a novel dual treatment system, consisting of a bone marrow mobilizing agent (VPC01091), hypothesized to "push" prohealing cells into the blood, and localized delivery of stromal cell-derived factor-1α (SDF-1α), to "pull" the cells to the injury site. Immediately after rotator cuff tendon injury in rat, the mobilizing agent was delivered systemically, and SDF-1α-loaded heparin-based microparticles were injected into the supraspinatus muscle. Regenerative and degenerative changes to supraspinatus muscle and the presence of inflammatory/immune cells, mesenchymal stem cells (MSCs), and satellite cells were assessed via flow cytometry and histology for up to 21 days. After dual treatment, significantly more MSCs (31.9 ± 8.0% single cells) and T lymphocytes (6.7 ± 4.3 per 20 × field of view) were observed in supraspinatus muscle 7 days after injury and treatment compared to injury alone (14.4 ± 6.5% single cells, 1.2 ± 0.7 per 20 × field of view), in addition to an elevated M2:M1 macrophage ratio (3.0 ± 0.5), an indicator of a proregenerative environment. These proregenerative cellular changes were accompanied by increased nascent fiber formation (indicated by embryonic myosin heavy chain staining) at day 7 compared to SDF-1α treatment alone, suggesting that this method may be a promising strategy to influence the early cellular response in muscle and promote a proregenerative microenvironment to increase muscle healing after severe rotator cuff tear.

Quiste gigante acromioclavicular en paciente mayor. Hasta cuando tratar la causa.

Introduction: Acromioclavicular joint cysts are a rare entity, generally present in elderly patients with chronic injuries or arthropathies of the rotator cuff. There are several causes of cyst formation, there are generally two of the most frequent, which we will talk about in this article. Clinical case: We present the case of an 82-year-old male patient with a giant acromioclavicular cyst, more than 20 cm in diameter, with rapid growth in recent months and with associated rotator cuff tendon injury. Discussion: These cysts are not very frequent injuries, mainly caused by degeneration of the acromioclavicular joint, most of the cases associated with rotator cuff injuries. Diagnosis is based on clinical examination, ultrasound and magnetic resonance imaging. Treatment by cyst aspiration and corticosteroid infiltration is not usually very effective and has a high recurrence rate, so surgical removal of the cyst is more indicated. Conclusions: The surgical indication for these cysts is pain, sometimes associated with resection of distal fragments of the clavicle; when a rotator cuff injury is present, reverse shoulder arthroplasty can be an alternative; however, in patients with poor symptoms, simple excision of the cyst can be an effective treatment.

Rotator Cuff Tendon Repair after Injury in Hyperlipidemic Swine Decreases Biomechanical Properties.

Rotator cuff injury is the leading cause of shoulder pain. Hyperlipidemia is responsible in depositing lipids in tendons and reduce the healing upon injuries or tears. In this study, we created rotator cuff injury and repair models in swine and studied the changes in biomechanical properties of infraspinatus tendons in hyperlipidemic swine. The infraspinatus tendons from control group, hyperlipidemic injury and repair group of animals were collected and tested ex-vivo. The ultimate tensile strength (UTS) and modulus of elasticity increased in the tendons from the contralateral side on both the injury and repair models and were higher than the injury side. The presence of large number of fibrous tissues in the surgical site of repair and increased water content was observed in addition to the fatty infiltration which would have contributed to the decreased mechanical properties of the injured tendons following repair. Meanwhile the tendons of the contralateral side in both the injury and repair model showed adaptation to chronic load as observed in the modulus and viscoelastic properties. This is a pilot study that warrants detailed investigation in a larger sample size with longer duration following tendon injury and repair to gain better understanding on the effect of hyperlipidemia in the healing of rotator cuff tendon injury.

Pathological alterations in the expression status of rotator cuff tendon matrix components in hyperlipidemia.

Hyperlipidemia is an important risk factor in the development and progression of tendon pathology, however its role in aggravating rotator cuff tendon injury (RCTI) is largely unknown. We aimed to assess the expression status of key extracellular matrix (ECM) components in the tendon tissues and tenocytes under hyperlipidemia. Shoulder rotator cuff (RC) tendon tissues harvested from the swine model of hyperlipidemia displayed alterations in histomorphometry and the expression status of major ECM component proteins including COL-I, COL-III, COL-IV, COL-V, COL-VI, MMP2, and MMP9. Similarly, the LDL- and oxLDL-challenged tenocytes displayed altered expression of the same proteins at both transcriptional and translational levels. In addition, the lipid uptake and cellular reactive oxygen radicals predominated in the lipid-challenged tenocytes compared to the control. Overall, the LDL-treated cells displayed predominant pathological alterations compared to the ox-LDL-treated cells. Further understanding regarding the underlying molecular mechanisms driving the tendon matrisome alteration and subsequent aggravated RCTI pathology in hyperlipidemia could open novel translational avenues in the management of RCTI.

Diagnostic Value of Clinical Tests in Patients with Rotator Cuff Arthropathy

Relevance. There are a large number of clinical tests for the diagnosis of rotator cuff tendon injuries and their consequences. Timely collected anamnesis and a thorough clinical examination are the key to an accurate diagnosis and the choice of treatment tactics.
 Objective: to determine the diagnostic value of clinical tests in patients with rotator cuff arthropathy.
 Materials and Methods. Clinical examination and surgical treatment of 110 patients with pathology of the shoulder joint, who had limited or complete lack of movement in the shoulder joint. The study of clinical results was performed in 2 groups: group I (60 patients) with rotator cuff arthropathy and group II (50 patients) with osteonecrosis of the humeral head. All patients were examined according to a single standard (clinical, radiological, and MRI examination). The clinical examination was performed in the standard way with special tests: the Jobe test, the Neer test, the Full can test, the Patte test, the Lift-off test, and the Hawkins-Kennedy test.
 Results and Conclusions. As a result of the analysis of clinical research data in patients with rotator cuff arthropathy, it was established that the clinical picture was distinguished by the polymorphism of manifestations and was closely related to undiagnosed damage to the structures of the shoulder joint. In patients with rotator cuff arthropathy, the most informative tests were (1) the Lift-off test: sensitivity (95.45%), specificity (73.33%), accuracy (86.49%), positive predictive value (PVP) (84.00%) and negative predictive value (PVN) (91.67%), and (2) the Full can test: sensitivity (89.80%), specificity (72.50%), accuracy (82.02%), as well as PVP (80.00%) and PVN (85.29%). In patients with rotator cuff arthropathy, the pain syndrome remained in most cases, which increased the sensitivity of the Lift-off test to 95.45% and the Full can test to 89.80%. The least specific clinical tests in patients with rotator cuff arthropathy were the Patte test (63.83%) and the Hawkins-Kennedy test (58.82%). No clinical test is reliable enough to diagnose rotator cuff arthropathy or osteonecrosis.

The effects of maturation and aging on the rotator cuff tendon-to-bone interface.

Rotator cuff tendon injuries often occur at the tendon-to-bone interface (i.e., enthesis) area, with a high prevalence for the elderly population, but the underlying reason for this phenomenon is still unknown. The objective of this study is to identify the histological, molecular, and biomechanical alterations of the rotator cuff enthesis with maturation and aging in a mouse model. Four different age groups of mice (newborn, young, adult, and old) were studied. Striking variations of the entheses were observed between the newborn and other matured groups, with collagen content, proteoglycan deposition, collagen fiber dispersion was significantly higher in the newborn group. The compositional and histological features of young, adult, and old groups did not show significant differences, except having increased proteoglycan deposition and thinner collagen fibers at the insertion sites in the old group. Nanoindentation testing showed that the old group had a smaller compressive modulus at the insertion site when compared with other groups. However, tensile mechanical testing reported that the old group demonstrated a significantly higher failure stress when compared with the young and adult groups. The proteomics analysis detected dramatic differences in protein content between newborn and young groups but minor changes among young, adult, and old groups. These results demonstrated: (1) the significant alterations of the enthesis composition and structure occur from the newborn to the young time period; (2) the increased risk of rotator cuff tendon injuries in the elderly population is not solely because of old age alone in the rodent model.

Hybrid interpenetrating hydrogel network favoring the bidirectional migration of tenocytes for rotator cuff tendon regeneration.

Replenishment of tenocytes to the injury site is an ideal strategy to improve healing response and accelerate the tendon ECM regeneration. The present study focused on the synthesis and characterization of a hybrid hydrogel scaffold system poly(propylene-fumarate)-alginate-polyvinyl alcohol-acrylic acid (PAPA) using poly(propylene-fumarate) (PPF), alginate, polyvinyl alcohol (PVA) and acrylic acid and the in vitro investigation of bidirectional mobility of swine shoulder tenocytes (SST) for its potential application in rotator-cuff tendon regeneration. IR analysis revealed the presence of alginate, PPF and PVA segments on the surface, SEM and AFM analyses revealed the porous and nano-topographical features of PAPA, respectively, swelling was 712.6 ± 84.21% with the EWC (%) of 87.59 ± 1.26 having the diffusional exponent and swelling constant 0.551 and 1.8, respectively. PAPA was biodegradable, cytocompatible and supported long-term survival of SSTs. SEM imaging revealed the adhesion, colonization, and sheet formation of SSTs within the PAPA hydrogel network. The SSTs seeded on the PAPA scaffolds were peculiar for their bidirectional migration as the anterograde movement was completed in 9 days whereas the retrograde infiltration occurred up to the depth of 198 μm. These findings suggest the promising translational potential of PAPA scaffold system in the management of rotator cuff tendon injury.

Could radio-morphological changes in humerus greater tuberosity be an early indicator of rotator cuff tendon injuries?

To reveal the possible relationship between greater tuberosity volume with rotator cuff tendon injuries. In our study, the morphology of the greater tuberosity was evaluated retrospectively by using radiographs and MR images of 335 cases. While critical shoulder angle (CSA) was measured on radiographs, greater tuberosity (GT) area and volume were calculated, and also supraspinatus, infraspinatus, and teres minor tendons were evaluated, on MR images. The relationship of the measurements with the tendon injuries was analyzed statistically. Among 188 female and 147 male patients, no statistically significant relationship was found between tendon injuries in terms of gender. The relationships between supra and infraspinatus tendon injuries and GT angle, area, and volume measurements were statistically significant. There was a statistically significant relationship between teres minor injury and GT angle, but no significant correlation with GT area and volume. Finally, there was no statistically significant correlation between all three tendon pathologies and CSA. Area, and especially volume measurements, which are morphological features of the GT, may reflect tendon damage without significant degenerative changes in the bone structure. In examinations before tendon damage progresses, GT volume is a morphological feature that needs to be evaluated and may facilitate early recognition of tendinopathies and be an early marker of rotator cuff injuries.

Evaluation of the relationship between subacromial space volume and rotator cuff injury by Magnetic Resonance Imaging with SPACE technique

Aim: To investigate the relationship between the degree of tearing in the rotator cuff tendons and the subacromial region volume using the proton-density weighted Sampling Perfection with Application optimized Contrasts using different flip angle Evolution technique and the contribution of this technique to shoulder magnetic resonance imaging. Material and methods: A total of 125 patients who underwent shoulder magnetic resonance imaging for shoulder pain between January 2016 and December 2016 were included in this single-center, retrospective study. Rotator cuff tendon injury grading was performed using coronal plane 2D short tau inversion recovery T2-weighted sequences (grades 1–4). Subacromial region volume was calculated from PD-weighted 3D SPACE sequence images in sagittal oblique plane. The relationship between rotator cuff tears and subacromial region volumes was evaluated using Pearson’s correlation analysis. The measurements were made at different times by two independent radiologists. Results: There was a strong negative correlation between the grade of RC tendon tear and subacromial volume (p<0.05; r: -0.83). Conclusion: Shoulder magnetic resonance imaging with high-contrast resolution can be obtained by the Sampling Perfection with Application optimized Contrasts using different flip angle Evolution technique. The degree of rotator cuff tendon tear, which is a cause of shoulder pain, is associated with the subacromial region volume. Using the Sampling Perfection with Application optimized Contrasts using different flip angle Evolution technique can also easily reveal the cause of the damage.

ROTATOR CUFF TENDON INJURY - AN AYURVEDA MANAGEMENT WITH JALOUKAVACARANA

Most shoulder pain is related to muscle or tendon strain. Chronic pain is often triggered by prior injuries, especially if original injury was severe or was not allowed to heal completely. Shoulder injury can cause weakness, tenderness and loss of full joint mobility. More common and less traumatic causes include lifting, reaching and pulling move- ments that strain the muscles and tendons or sprain ligaments surrounding the shoulder joint. Injury may or may not be realized during the activity. Various conditions like shoulder joint impingement, frozen shoulder, and rotator cuff tendinitis have resembling symptoms under the umbrella of disease Avabahuka described in Ayurveda. Leech application was carried out in first stage where there is reduced vascular supply. Here a case report of a female aged 31years old, who had an acute on chronic rotator cuff strain from strenuous activity underwent three sittings of Jaloukavacarana. Keywords: Rotator cuff tendon injury, Avabahuka, Jaloukavacarana.

Elite professional goalkeepers report high rate of sport resumption after shoulder surgery.

The aim of this study is to evaluate the return to sport after surgical treatment of shoulder injuries in professional goalkeepers in relationship with the mechanism of injury and the pattern of related shoulder lesions. Twenty-six shoulders in nineteen elite male professional soccer goalkeepers were retrospectively analyzed considering multiple diseases (instability, rotator cuff, biceps or other tendon injuries). Data was collected for injury modality and context, pathological findings, surgical procedures, time, level of return to sport, and complications. The mechanism of injury was "mild trauma without contact" in 46% of the cases and 54% of injuries happened during training. 11 patients (42%) reported multiple pattern lesions and 9 patients (35%) classic anterior instability lesions. The mean time for return to differentiated training and unrestricted sport activity was 14 and 20.2 weeks, respectively. 15 athletes (62.5%) reported 100% return to sport, 4 (16.7%) to 90%, 1 (4.2%) to 85%, 3 (12.5%) to 80% and 1 athlete to 50%, stopping professional activity. 21% of the cases reported the persistence of some shoulder symptoms. 3 cases experienced a new injury. Patients with classic anterior instability had significantly lower age (30.7 vs 19.8 years, P=0.001), experienced injury in different context and reported symptoms more frequently compared to multiple lesion patients (4/8 vs 0/10, P=0.011). Professional elite goalkeepers which required shoulder surgery for different causes demonstrated high-rate level of return to play despite the persistence of mild symptoms. The high frequency of multiple lesions, patients' characteristics, injury context and mechanism, increase the concern for injuries in overstressed shoulder for this category of sport. IV.

Prevalence and Grading of Rotator Cuff and Labral Injuries in Shoulder Pain and Instability using MRI: ACross-sectional Study

Introduction: Shoulder joint is a highly mobile joint but is prone for rotator cuff injuries and dislocations. It is necessary to accurately diagnose rotator cuff and labral injuries so that appropriate plan of action for treatment can be taken. Magnetic Resonance Imaging (MRI) can be used to diagnose and describe the extent of rotator cuff tendon and labral injuries and any secondary rotator cuff muscle abnormalities. Aim: To study the demographic profile of patients presenting with shoulder pain and instability, identify the various rotator cuff injuries causing shoulder pain, identify the rotator cuff interval lesions causing microinstability, identify the various labral and bony pathologies in instability, describe the MRI features of the rotator cuff, rotator cuff interval, labral and bony injuries. Materials and Methods: This study was a cross-sectional study of patients with symptoms of either shoulder pain or instability who underwent MRI evaluation of the shoulder in the Department of Radiodiagnosis, Rajarajeswari Medical College and Hospital, Bengaluru, Karnataka, India, from July 2018 to December 2020. The study population consisted of 54 patients with either shoulder pain or instability who underwent MRI of shoulder. All the MRI scans of the shoulder in this study were performed using 1.5 Tesla Siemens Magnetom Avanto (Tim 76x18) MR machine using a flex coil. Results: The study population consisted of 54 patients comprising of 38 males and 16 females. The age of the patients ranged from 20-77 years. Majority of the patients were older than 50 years constituting about 33.33% of the total study population. Rotator cuff injury was the commonest cause of pain. Tendinosis was the commonest type of rotator cuff injury followed by partial-thickness and full-thickness tendon tears. The commonest grade of tendinosis was mild or grade 1. Supraspinatus tendon was the most commonly affected tendon followed by subscapularis and infraspinatus tendons. Teres minor tendon was normal in all the cases. Anterior instability was the commonest type of instability with equal prevalence of soft tissue Bankart, bony Bankart and Perthes lesions. Biceps pulley lesions resulted in long head of biceps tendon instability, microinstability and internal impingement. Conclusion: Rotator cuff injuries are the commonest cause of shoulder pain and are seen more frequently after the fifth decade. Shoulder instability is most commonly seen in young male adults. Tendinosis is the commonest type of rotator cuff injury. Supraspinatus tendon is the most commonly injured tendon. Anterior instability is the commonest type of shoulder instability. Biceps pulley lesions result in long head of biceps tendon instability, microinstability and internal impingement. MRI can diagnose interstitial or intrasubstance tendon tears which are not visualised on arthroscopy. MRI description of tendon and labral tears, tendon retraction and muscle atrophy can guide the orthopaedician during arthroscopy and in treatmentplanning.

DATA FROM CLINICAL AND INSTRUMENTAL EXAMINATIONS OF PATIENTS WITH CHRONIC PAIN IN THE SHOULDER JOINT

Chronic shoulder pain (CSP) is one of the most common reasons for seeking medical care. Identifying the specific cause of CSP is necessary to determine the treatment strategy. Objective: to determine which pathology of the musculoskeletal system is the main cause of CSP. Subjects and methods . A study group consisted of 151 patients (49.7% females; mean age, 49.8±18.8 years), who experienced shoulder joint pain that persisted when taking nonsteroidal anti-inflammatory drugs (NSAIDs) and after local administration of glucocorticoids. They underwent clinical and instrumental studies (radiography, magnetic resonance imaging, and ultrasound). The investigators assessed pain intensity using a visual analogue scale (VAS), and functional impairment with the American Shoulder and Elbow Surgeons (ASES) Assessment Scores and the Constant Score (CS). Results and discussion. The mean CSP intensity at rest and during movement was 56.1±21.7 and 67.3±19.1 mm VAS. The degree of functional disorders was 55.5±17.6 ASES scores and 54.1±14.5 CS scores. Tendonitis that is an injury to the tendon of the supraspinatus muscle (74.8%) was most common. There was shoulder osteoarthritis (OA) in 31.7%, acromioclavicular (AC) OA in 19.2%, rotator cuff tendon injury concurrent with shoulder OA in 25.2%, that with AC OA in 16.6%, and that with shoulder OA and AC OA in 9.2%. The intensity of pain with only rotator cuff tendon injury and that concurrent with shoulder OA and/or AC OA did not differ and that averaged 57.2±20.2 and 54.6±18.6 mm at rest, respectively, and 68.3±22.4 and 65.4±19.2 mm during movement (p>0.05 in both cases). Conclusion. The main cause of CSP is tendonitis of the rotator cuff, primarily of the supraspinatus muscle. Moreover, more than half of patients have rotator cuff tendon injury concurrent with biceps tendon injury, shoulder OA and/or AC OA.

Partial Infraspinatus Tendon Transection as a Means for the Development of a Translational Ovine Chronic Rotator Cuff Disease Model.

Rotator cuff tendon tears are the most common soft tissue injuries in the shoulder joint. Various animal models have been described for this condition, but all current translational animal models have inherent weaknesses in their ability to generate chronically degenerated rotator cuff tendons. The objective of this study was to evaluate a partial infraspinatus tendon transection model as a means of creating a chronically degenerated rotator cuff tendon in an ovine model and compare the injury characteristics of this model to those observed in human patients with severe chronic rotator cuff tendon injuries. The infraspinatus tendons of six sheep were partially detached followed by capping of the detached medial section of the tendon with Gore-Tex. Human tissue samples of the supraspinatus tendon were harvested from patients undergoing primary reverse shoulder arthroplasty and served as positive controls of chronic rotator cuff tendinopathy. Transected sheep tendons were characterized predominantly by an acute reactive and reparative pathological process as compared with the chronic degenerative changes observed in the human tendons. In contrast, the non-transected portion of the ovine tendon showed histological changes, which were more chronic and degenerative in nature when compared with the transected tendon. Overall, histological features of the non-transected portion of ovine tendon were more similar to those observed in the chronic degenerated human tendon.

Вплив ушкоджень м’якотканинних структур плечового суглоба на розвиток омартрозу

Summary. Injury of the soft tissue structures of the shoulder joint (rotator cuff, scapula labrum, etc.) is a common cause of omarthrosis. Objective: to investigate the changes in the articular cartilage of the shoulder head and the scapula glenoid in case of the soft tissue structures of the shoulder joint injury. Materials and Methods. We studied the long-term results of conservative and surgical treatment of 330 patients with soft tissue injuries of the shoulder joint, who were treated in the SI “Institute of Traumatology and Orthopedics of NAMS of Ukraine” (Kyiv) from 2009 to 2019. The age of patients ranged from 27 to 68 years (mean age 42.7±19.5 years); 225 were males (68.2%) and 105 females (31.8%). Surgical treatment was performed in 160 patients (48.5%); 170 patients (51.5%) underwent conservative treatment. For evaluation of the influence of the shoulder soft tissue structures injury on the articular cartilage, the degree of the articular cartilage damage was determined by R. Outerbridge and the obtained data were compared with the period from the onset of the disease to surgery. Conclusions: 1. The largest number of secondary omarthroses develops after ruptures of the rotator cuff tendons, both in conservative and surgical groups. Thus, a rupture of rotator cuff tendons is the most arthrosogenic factor among all soft tissue pathology of a shoulder joint. 2. Another arthrosogenic factor for the shoulder joint is rupture of the glenoid labrum in the anterior-inferior part in case of anterior shoulder dislocation and rupture of the posterior glenoid labrum without posterior dislocation (unrealized posterior instability), probably due to high energy trauma and trophic disorders of humeral head after dislocation. 3. A weak but significant dependence was found of the effect of the time from the beginning of the disease to surgery in various Pulley lesions on the degree of damage to the articular cartilage according to R. Outerbridge (r=0.4; p&lt;0.05). Thus, early diagnosis and surgical treatment of Pulley lesions is a major prevention of omarthrosis. 4. A weak but significant dependence of the influence of the period from the onset of the disease to surgery was revealed in patients with isolated injury of the supraspinatus tendon (r=0.38; p&lt;0.05). Early diagnosis and surgical treatment of rotator cuff tendon injuries is the main prevention of omarthrosis.

Matrix regeneration proteins in the hypoxia-triggered exosomes of shoulder tenocytes and adipose-derived mesenchymal stem cells.

Regenerative functions of exosomes rely on their contents which are influenced by pathological stimuli, including hypoxia, in rotator cuff tendon injuries (RCTI). The hypoxic environment triggers tenocytes and adjacent adipose-derived mesenchymal stem cells (ADMSCs) to release regenerative mediators to the ECM via the exosomes which elicit autocrine/paracrine responses to protect the tendon matrix from injury. We investigated the exosomal protein contents from tenocytes and subcutaneous ADMSCs from the shoulder of Yucatan microswine cultured under hypoxic conditions (2% O2). The exosomal proteins were detected using high-resolution mass spectrometry nano-LC-MS/MS Tribrid system and were compiled using 'Scaffold' software. Hypoxic exosomes from tenocytes and ADMSCs carried 199 and 65 proteins, respectively. The key proteins identified by mass spectrometry and associated with ECM homeostasis from hypoxic ADMSCs included MMP2, COL6A, CTSD and TN-C and those from hypoxic tenocytes were THSB1, NSEP1, ITIH4 and TN-C. These findings were confirmed at the mRNA and protein level in the hypoxic ADMSCs and tenocytes. These proteins are involved in multiple signaling pathways of ECM repair/regeneration. This warrants further investigations for their translational significance in the management of RCTI.

Paper #22 - Muscle-derived activated endothelial cells as a new cell source to enhance tendon-to-bone healing: in vivo study in a murine rotator cuff repair model

Introduction: Cell-based approaches are expected to improve tendon-to-bone healing in rotator cuff tendon injuries. Recently, a specialized population of endothelial cells which produce signaling molecules that stimulate the intrinsic stem cells in specific tissues have been identified and reported. 4 Lebaschi A. Camp C. Carballo C. Cong G.-T. Album Z. Ying L. et al. Murine Supraspinatus Tendon Detachment and Repair Model Augmented With Tendon-Derived, Activated Endothelial Cells: A New Concept in Biologic Enhancement of Tendon-to-Bone Healing. In Annual Meeting of the Orthopedic Research Society. 2017http://dx.doi.org/10.1002/jor.23581 Google Scholar We hypothesized that endothelial cells from muscle tissue could stimulate and enhance the tendon-to-bone healing. The purpose of the present study is to evaluate the effects of the novel muscle-derived activated endothelial cells (mECs) implanted at the repair site in a murine rotator cuff repair model.

Amplification of Mitochondrial Activity in the Healing Response Following Rotator Cuff Tendon Injury

Mitochondrial function following rotator cuff tendon injury (RCI) influences the tendon healing. We examined the mitochondrial morphology and function under hypoxia in the shoulder tendon tissue from surgically-induced tenotomy-RCI rat model and cultured swine tenocytes. The tendon tissue was collected post-injury on 3–5 (Group-A), 10–12 (Group-B), and 22–24 (Group-C), days and the corresponding contralateral tendons were used as control for each group. There was higher protein expression of citrate synthase (P < 0.0001) [10.22 MFI (mean fluorescent intensity)] and complex-1 (P = 0.0008) (7.86 MFI) in Group-A and Group-B that decreased in Group-C [(P = 0.0201) (5.78 MFI and (P = 0.7915) (2.32 MFI), respectively] compared to control tendons. The ratio of BAX:Bcl2 (Bcl2 associated x protein:B cell lymphoma 2) in RCI tendons increased by 50.5% (Group-A) and 68.4% (Group-B) and decreased by 25.8% (Group-C) compared to normoxic controls. Hypoxia increased β-tubulin expression (P = 0067) and reduced PGC1-α (P = 0412) expression in the isolated swine tenocytes with no effect on the protein expression of Complex-1 (P = 7409) and citrate synthase (P = 0.3290). Also, the hypoxic tenocytes exhibited about 4-fold increase in mitochondrial superoxide (P < 0.0001), altered morphology and mitochondrial pore integrity, and increase in mitochondrial density compared to normoxic controls. These findings suggest the critical role of mitochondria in the RCI healing response.