Rotator Cuff Tendon Research Articles

Medialized Rip-Stop Convergence Technique for Retracted Rotator Cuff Tears

Attempts to restore the anatomical footprint during rotator cuff repair for retracted, relatively immobile tears can be difficult. In some cases, it can lead to excessive tension of the repair. Previous studies have noted improved clinical outcomes when repair tension is not excessive, and medialization of the anatomical footprint has been suggested as a technique that can help surgeons repair large, retracted tears without excessive tension and achieve improved clinical outcomes. Of note, excessive tension when restoring the rotator cuff tendon to the anatomical footprint is not limited to large, retracted tears. In some cases, restoring small- and medium-sized tears to the anatomical footprint also can lead to excessive tension. Therefore, it is not uncommon for the authors to employ some degree of footprint medialization even for repair of small- or medium-sized tears if repair to the anatomical footprint will lead to excess tension. The purpose of this article and video demonstration is to provide instruction for a reproducible rotator cuff technique using a medialized single-row rip-stop construct combined with convergence.

Revision rotator cuff repair: can a Sugaya III tendon considered to be healed or not

Sugaya etal described a classification system to assess postoperative rotator cuff tendon healing. Although Sugaya I and II tendons can be considered as healed and Sugaya type IV and V can be considered as retorn, the exact status of Sugaya III tendons remains unclear. The objective of this study was to evaluate the impact of Sugaya III tendons on postoperative functional scores in a population of patients undergoing revision rotator cuff repair. We retrospectively studied the records of all patients who underwent revision rotator cuff repair in one of 12 different institutions between July 2001 and December 2020. A total of 203 shoulders were included (59% males, mean age: 51±8 years old, mean follow-up 11.5 years [range: 2-28.8 yr]). Fifty-four patients (61% males, mean age 52±6 years old, mean follow-up 14.1 years [range: 10.4-28.8 yr]) had a follow-up≥10 years (mean 14.1 years [range: 10.4-28.8 yr]) and were included in a long-term follow-up subgroup analysis. Structural integrity of the repaired tendon was evaluated on magnetic resonance imaging at last follow-up. Functional scores, acromiohumeral index (AHI), and progression of fatty infiltration and of osteoarthritis were compared according to Sugaya type. Mean Constant score and mean strength were significantly higher in Sugaya I and II tendons than in Sugaya III (P=.021 and .003) and Sugaya IV and V tendons (P=.07 and .038), but did not differ between Sugaya III and Sugaya IV and V tendons. Mean Subjective Shoulder Value, pain, AHI were significantly higher and fatty infiltration and progression in the Hamada classification were significantly lower in Sugaya I and II tendons and in Sugaya III than in Sugaya IV and V tendons (P< .05), but did not differ between Sugaya I and II and Sugaya III tendons. Similar characteristics could also be observed in the long-term follow-up subgroup. Sugaya III tendons after revision rotator cuff repair do not allow restoration of strength thereby impacting the Constant score. However, there seems to be a protective effect of Sugaya III tendons with regard to pain, progression of proximal migration of the humeral head, osteoarthritis, and fatty infiltration, which seems to last at long-term follow-up.

The effect of augmenting suture material with magnesium and platelet-rich plasma on the in vitro adhesion and proliferation potential of subacromial bursa-derived progenitor cells

Connective tissue subacromial bursa-derived progenitor cells (SBDCs) have been suggested as a potent biologic augment to promote healing of the repaired rotator cuff tendon. Maximizing the amount of retained progenitor cells at the tendon repair site is essential for ensuring an optimal healing environment, warranting a search for proadhesive and proliferative adjuvants. The purpose was to evaluate the effect of magnesium (Mg), platelet-rich plasma (PRP), and a combination of both adjuvants on the invitro cellular adhesion and proliferation potential of SBDCs on suture material commonly used in rotator cuff surgery. SBDCs were isolated from subacromial bursa samples harvested during rotator cuff repair and cultured in growth media. Commercially available collagen-coated nonabsorbable flat-braided suture was cut into 1-inch pieces, placed into 48-well culture dishes, and sterilized under ultraviolet light. Either a one-time dose of 5 mM sterile Mg, 0.2 mL of PRP, or a combination of both adjuvants was added, while a group without treatment served as a negative control. Cellular proliferation and adhesion assays on suture material were performed for each treatment condition. Augmenting the suture with Mg resulted in a significantly increased cellular adhesion (total number of attached cells) of SBDCs compared to PRP alone (31,527±19,884 vs. 13,619±8808; P<.001), no treatment (31,527±19,884 vs. 21,643±8194; P=.016), and combination of both adjuvants (31,527±19,884 vs. 17,121±11,935; P<.001). Further, augmentation with Mg achieved a significant increase in cellular proliferation (absorbance) of SBDCs on suture material when compared to the PRP (0.516±0.207 vs. 0.424±0.131; P=.001) and no treatment (0.516±0.207 vs. 0.383±0.094; P<.001) group. The combination of Mg and PRP showed a significantly higher proliferation potential compared to PRP alone (0.512±0.194 vs. 0.424±0.131; P=.001) and no treatment (0.512±0.194 vs. 0.383±0.094; P<.001). There were no significant differences in the remaining intergroup comparisons (P>.05, respectively). Augmenting suture material with Mg resulted in a significantly increased cellular adhesion of SBDCs compared to untreated suture material, as well as augmentation with PRP alone or a combination of both adjuvants. Further, Mg with or without PRP augmentation achieved a significant increase in the cellular proliferation of SBDCs on suture material compared to untreated sutures and augmentation with PRP alone. Application of Mg may be a clinically feasible approach to optimizing the use of SBDCs as a biological augment in rotator cuff repair, while combined augmentation with PRP may harness the full potential for optimized tissue recovery due to the high concentration of PRP-derived growth factors.

Potential function of Scx+/Sox9+ cells as progenitor cells in rotator cuff tear repair in rats

Tendons and their attachment sites to bone, fibrocartilaginous tissues, have poor self-repair capacity when they rupture, and have risks of retear even after surgical repair. Thus, defining mechanisms underlying their repair is required in order to stimulate tendon repairing capacity. Here we used a rat surgical rotator cuff tear repair model and identified cells expressing the transcription factors Scleraxis (Scx) and SRY-box 9 (Sox9) as playing a crucial role in rotator cuff tendon-to-bone repair. Given the challenges of establishing stably reproducible models of surgical rotator cuff tear repair in mice, we newly established Scx-GFP transgenic rats in which Scx expression can be monitored by GFP. We observed tissue-specific GFP expression along tendons in developing ScxGFP transgenic rats and were able to successfully monitor tissue-specific Scx expression based on GFP signals. Among 3-, 6-, and 12-week-old ScxGFP rats, Scx+/Sox9+ cells were most abundant in 3-week-old rats near the site of humerus bone attachment to the rotator cuff tendon, while we observed significantly fewer cells in the same area in 6- or 12-week-old rats. We then applied a rotator cuff repair model using ScxGFP rats and observed the largest number of Scx+/Sox9+ cells at postoperative repair sites of 3-week-old relative to 6- or 12-week-old rats. Tendons attach to bone via fibrocartilaginous tissue, and cartilage-like tissue was seen at repair sites of 3-week-old but not 6- or 12-week-old rats during postoperative evaluation. Our findings suggest that Scx+/Sox9+ cells may function in rotator cuff repair, and that ScxGFP rats could serve as useful tools to develop therapies to promote rotator cuff repair by enabling analysis of these activities.

Influence of Vitamin D Deficiency on the Expression of Genes and Proteins in Patients With Medium Rotator Cuff Tears.

Whether vitamin D deficiency is related to rotator cuff muscle and tendon physiology is controversial. To assess the relationship between vitamin D deficiency and various gene expression patterns in patients with rotator cuff tears. Controlled laboratory study. During arthroscopic surgery, samples from the supraspinatus muscle, deltoid muscle, and supraspinatus tendon were acquired from 12 patients with vitamin D deficiency (serum 25-hydroxyvitamin D concentration <20 ng/dL) and 12 patients with sufficient vitamin D levels (control group, serum 25-hydroxyvitamin D concentration ≥30 ng/dL) who were matched for age, sex, and tear size. Alterations in the expression of genes and proteins associated with myogenesis, muscle atrophy, adipogenesis, inflammation, and apoptosis, as well as in vitamin D receptor expression, were assessed using quantitative reverse transcription polymerase chain reaction, Western blotting, and immunohistochemistry and were compared between the 2 groups. Vitamin D receptor gene expression in the deltoid muscle was significantly lower in the vitamin D deficiency group than in the control group (P = .043). Additionally, in the deltoid muscle, myoDgene expression levels were lower and atrogin levels were higher in the vitamin D deficiency group than in the control group (P = .034 and P = .011, respectively). However, in the supraspinatus muscle, no differences were observed between groups in the expression of myogenesis- or atrophy-related genes (all P > .05). The expression of inflammation-related genes (interleukin (IL)-1β and IL-6) was significantly higher in the vitamin D deficiency group, in both the deltoid and supraspinatus muscles (all P < .05). The supraspinatus tendon tissue did not show any significant differences in any gene expression evaluated (all P > .05). A correlation between gene and protein expression was observed for atrogin and IL-1β in the deltoid muscle (P = .019 and P = .037, respectively) and for IL-6 in the supraspinatus muscle (P = .044). Vitamin D deficiency was not associated with the expression of myogenesis-related or muscle atrophy-related genes in the supraspinatus muscle of patients with rotator cuff tears, unlike in the deltoid muscle; rather, vitamin D deficiency was associated with increased proinflammatory cytokine expression. In patients with rotator cuff tears, vitamin D deficiency was observed to be associated with increased levels of proinflammatory cytokines in the rotator cuff muscles, without significant changes in gene expression related to myogenesis or muscle atrophy.

Poster 202: Subacromial Decompression is Associated with a Number Needed to Treat of 4 for Reduced Revision Rotator Cuff Repair: A Large Matched Cohort Insurance Database Analysis

Objectives: Subacromial decompression (SAD) during arthroscopic rotator cuff repair (ARCR) has traditionally been performed to relieve impingement of the rotator cuff tendons as they pass through the subacromial space. The purpose of this study is to quantify the reduced risk of revision rotator cuff surgery conferred by performing SAD with ARCR. Methods: The PearlDiver administrative claims database was queried for patients who underwent ARCR between 2015-2020 with a minimum follow up of 2 years. The study population was stratified by whether concurrent SAD was performed at the time of the index ARCR. Groups were matched on age, gender, Charlson Comorbidity Index (CCI), complete versus partial tear, and comorbidities previously correlated with RCR healing. The primary outcome was requiring a revision rotator cuff repair. Results: The final analysis included 30,407 patients per group, with a mean age of 60 years (SD=7) and 45.3% women. Baseline demographics were similar between groups after matching. 551 (1.8%) patients without SAD vs. 437 patients with SAD (1.4%) underwent a revision rotator cuff repair, corresponding to a number needed to treat (NNT) of 3.8 (unadj-OR=0.79. 95% CI 0.70-0.90, P&lt;0.001). In a multivariable model, factors associated with revision rotator cuff repair included subacromial decompression (adj- OR=0.79, 95%CI 0.70-0.90, P&lt;0.001), male gender (adj-OR 0.97, 95% CI 0.97-0.98, P=0.017), older age (adj-OR=0.97, 95% CI 0.97-0.98, P&lt;0.001), complete tear (adj-OR=3.62, 95% CI 2.87-4.57, P&lt;0.001), tobacco use (adj-OR 1.33, 95% CI 1.12-1.52, P&lt;0.001), and CCI (adj-OR 1.05, 95% CI 1.01-1.09, P=0.027). Conclusions: In a large cohort of over 60,000 patients with partial or complete rotator cuff tears, performing concurrent SAD conferred a 26% relative risk reduction (NNT»4 patients) for revision rotator cuff repair when compared to ARCR alone. These findings suggest that SAD may reduce the risk of revision rotator cuff surgery. [Table: see text][Table: see text]

Poster 105: Rotator cuff healing using demineralised bone fibers in ovine infraspinatus tendon models

Objectives: Rotator cuff tears are a common cause of shoulder pain and functional deficits. Although surgical repair is often able to restore function and resolve pain, high rates of postoperative structural failures have been reported. To improve the outcomes and reduce re-tear rates biologic tissue scaffolds have been used to augment and reinforce the primary tendon repair by providing mechanical support of the initial repair and ideally improving the rate and/or quality of biological healing at the tendon-bone interface. Demineralised bone fibers (DBF) are bone collagen and can be formed into a patch providing a scaffold and inductive bone morphogenetic proteins known to facilitate healing. This study evaluated the in vivo response of human DBF Patches (hDBF-P) as an onlay over the infraspinatus tendon (IST) and at the tendon-bone interface in an ovine model. Methods: The hDBF-P was characterised using stereozoom (Figure 1A) and environment electron microscopy (Figure 1B). The osteoinductivity (OI) was evaluated in the standard nude rat intramuscular implantation (IM) model at 28 days using mCT and paraffin histology. A bilateral model of an onlay or an enthesis repair was performed in 12 adult wethers following ethical approval. Four groups were evaluated at 6 and 12 weeks (n=3 per time point): Onlay control and hDBF treated; Enthesis repair control and hDBF treated. The onlay model simulated a tendon injury by 4 longitudinal slits along the IST and lateral drill holes in the proximal humerus in the onlay control group [1]. In the onlay treated group the hDBF-P was hydrated in saline and secured to the IST with interrupted 2-0 non-resorbable sutures (Figure 2A). On contralateral side, the central third of the IST was sharply dissected, the footprint burred, and 2 medial row anchors inserted. The sutures were passed through the IST in the enthesis repair control group. In the enthesis repair treatment group, the sutures were passed through the hDBF-P which was placed at the tendon bone interface followed by sutures through the IST. Two lateral push lock anchors were used for a suture bridge (Figure 2B) in the control and treated groups. Endpoints included clinical recovery, macroscopic dissection, 3T MRI, radiographs, mCT and paraffin histology processing, H&amp;E staining, and light microscopic evaluations to assess local cell and tissue responses and healing. Results: OI was confirmed on IM implantation in nude rats. The sheep recovered uneventfully with no adverse events macroscopically or radiographically. MRI in the onlay control group revealed little response and no increase in tendon thickness which was confirmed histologically. In contrast the onlay hDBF-P treated demonstrated increased tendon thickness and hDBF resorption with time. Histology showed some initial inflammatory cells that decrease with time in the onlay group. MRI in the hDBF-P treated enthesis group supported increased activity at the bone interface at 6 and 12 weeks compared to controls. Histology at the interface with hDBF-P showed evidence of new bone formation at 6 weeks that matured with time support enthesis reformation. Conclusions: hDBF-P is a collagen graft composed of demineralized bone fibers that have osteoconductive and osteoinductive potential. When formed into a patch, this implant provides a scaffold that can participate with the local biology. hDBF-P used as on-lay in a tendon injury model increased tendon thickness. hDBF-P when used at the interface between the tendon and bone facilitated enthesis reformation through its conductive and inductive potential as well as scaffold architecture. DBF patches represent an exciting allograft implant with the potential to address the clinical problems in rotator cuff surgery. Literature cited Van Kampen, C., et al. (2013). Tissue-engineered augmentation of a rotator cuff tendon using a reconstituted collagen scaffold: a histological evaluation in sheep. Muscles, ligaments and tendons journal, 3(3), p.229.

Fracture line and comminution zone characteristics, and rotator cuff footprint involvement in OTA/AO 11C3-type proximal humeral fractures: complex proximal humerus fracture map.

To identify fracture characteristics and zones of comminution as well as the relationship with anatomic landmarks and rotator cuff footprint involvement in OTA/AO 11C3-type proximal humerus fractures. Computed tomography images of 201 OTA/AO 11C3 fractures were included. Fracture lines were superimposed to a 3D proximal humerus template, created from a healthy right humerus, after fracture fragment reduction on 3D reconstruction images. Rotator cuff tendon footprints were marked on the template. Lateral, anterior, posterior, medial, and superior views were captured for the interpretation of fracture line and comminution zone distribution as well as to define the relationship with anatomic landmarks and rotator cuff tendon footprints. A total of 106 females and 95 males (mean age = 57.5 ± 17.7 [range 18-101] years) with 103 C3.1-, 45 C3.2-, and 53 C3.3-type fractures were included. On the lateral, medial, and superior humeral surfaces, fracture lines and comminution zones were distributed differently in 3 groups. Tuberculum minus and medial calcar region were significantly less severely affected in C3.1 and C3.2 fractures than C3.3 fractures. The supraspinatus footprint was the most severely affected rotator cuff footprint area. Specifically defining the certain differences for repeatable fracture patterns and comminution zones in OTA/AO 11C3-type fractures and the relationship between the rotator cuff footprint and the joint capsule may contribute to the decision-making process of surgeons.

Association of Severe Histological Degeneration of the Torn Supraspinatus Tendon and Retear After Arthroscopic Repair of Full-Thickness Rotator Cuff Tears Using the Suture Bridge Technique

Background: Previous studies have demonstrated several prognostic factors for retear after arthroscopic rotator cuff repair (ARCR). However, studies that histologically evaluate the quality of the torn rotator cuff (RC) tendon and its association with postoperative outcomes are limited. Purpose: To investigate factors associated with retear after ARCR using the suture bridge (SB) technique, including the degree of histological degeneration of the RC tendon edge. Study Design: Case-control study; Level of evidence, 3. Methods: The authors retrospectively evaluated 187 patients who underwent ARCR for full-thickness tears using the SB technique; intraoperative biopsy samples were taken to assess the degree of histological degeneration using the Bonar score. The cohort was divided into healed (n = 165) and retear (n = 22) groups according to magnetic resonance imaging results obtained ≥6 months postoperatively. The evaluation included preoperative patient data (age, sex, symptom duration, trauma history, history of heavy manual work, smoking habit, hypertension, diabetes mellitus, and hyperlipidemia) and radiological data (Hamada classification, Patte classification, Goutallier classification, and global fatty degeneration index [GFDI]). Additionally, intraoperative data (anteroposterior tear size, Lafosse classification for concomitant subscapularis tendon tear, and long head of biceps injury) and preoperative and postoperative clinical findings (active range of motion, University of California, Los Angeles [UCLA], score) were evaluated. Results: The retear rate was 11.8%. The retear group had a higher percentage of men (P = .031), higher Bonar score (P < .001), higher mean GFDI value (P = .002), higher rate of tear retraction degree (P = .010), and larger anteroposterior tear size (P = .020) than the healed group. The retear group had lower postoperative internal rotation (P = .031) and lower UCLA score (P < .001). Multivariate logistic regression analysis with a stepwise variable selection revealed anteroposterior tear size (odds ratio [OR], 2.4; 95% CI, 1.3-4.5; P = .004) and Bonar score (OR, 1.7; 95% CI, 1.3-2.4; P < .001) as independent predictors for a retear. Conclusion: The results indicate that end-stage severe tendon degeneration might affect retear. Therefore, further investigation on the progression mechanisms of tendon degeneration and development of methods to assess degenerative tissue might improve clinical outcomes after ARCR.

Impact of Rotator Cuff Tendon Thickness on Functional Outcomes after Arthroscopic Repair - A 2-Year Follow Up Study on Small-Medium Sized Tears in Elderly Patients

Impact of Rotator Cuff Tendon Thickness on Functional Outcomes after Arthroscopic Repair - A 2-Year Follow Up Study on Small-Medium Sized Tears in Elderly Patients

Short-term Outcomes of an “All-In-One” Interpositional Scaffold Anchor Implant for Rotator Cuff Tendon Repair: A Prospective Multicenter Study

Short-term Outcomes of an “All-In-One” Interpositional Scaffold Anchor Implant for Rotator Cuff Tendon Repair: A Prospective Multicenter Study

Intraosseous extension of supraspinatus calcific tendonitis in a young patient with severe shoulder pain: a rare case report

Abstract Calcific tendinopathy is one of the causes of shoulder pain and limited range of motion when it affects the rotator cuff tendons. Complications of such a condition are rare and include intraosseous and intramuscular migration. Calcific tendonitis can be classified as acute, subacute or chronic based on the onset of symptoms. The incidence of calcific tendonitis affects females more than males, with the median age of onset being between 40 and 60 years old. Diagnostic modalities include radiographs and computed tomography (CT); however, these are suboptimal when compared to the sensitivity of magnetic resonance imaging. Ninety percent of these cases are treated non-surgically. We present a rare case of a young female patient with right shoulder pain and limited range of motion secondary to the intraosseous migration of calcific tendonitis. The patient’s symptoms were resolved after a CT-guided percutaneous bone biopsy of the lesion. Clinical correlation with the aid of imaging and histopathology is a multimodal approach to help diagnose and treat such conditions.

Ultrasound Detects Increased Vascularity Following Rotator Cuff Tears Compared to Asymptomatic snd Repaired Rotator Cuff Tendons

Ultrasound Detects Increased Vascularity Following Rotator Cuff Tears Compared to Asymptomatic snd Repaired Rotator Cuff Tendons

Irreparable Rotator Cuff Tear Treated With Combined Reconstruction of the Superior Capsule and Rotator Cuff: Technique Guidelines

Irreparable rotator cuff tears in young patients can be challenging for the patient and orthopaedic surgeon. Interposition rotator cuff reconstruction has gained popularity in patients with retracted tears and a viable rotator cuff muscle belly. Superior capsular reconstruction is an emerging treatment option that was developed to restore native glenohumeral joint mechanics by creating a superior constraint, which provides a stable glenohumeral fulcrum. Reconstructing both the superior capsule and rotator cuff tendon in the setting of an irreparable tear may improve clinical results in younger patients with viable rotator cuff muscle belly and a maintained acceptable acromiohumeral distance.

Thermal analysis of tendon, cartilage and bone samples from shoulder joint replacement patients using differential scanning calorimetry (DSC) and thermogravimetry (DTA/TG)

AbstractDespite advanced imaging techniques, more information on the extent of joint degeneration and modifications in tendon collagen content is required for selecting the appropriate type of shoulder prosthesis. The goal of this study was to compare the thermal parameters of various tissue samples from patients who had shoulder arthroplasty and to correlate the thermal shifts with the outcomes of radiological and histopathological assessments. Rotator cuff (ROC) tendon, hyaline cartilage, and subchondral bone samples were obtained throughout surgery for a comminuted 4-part proximal humerus fracture or cuff tear arthropathy. Thermal parameters were measured using differential scanning calorimetry and thermogravimetry (DTA/TG). ROC: The effect of advanced collagen damage was visible in denaturation curves of osteoarthritis samples. Only moderately increased thermal enthalpy and melting temperature were found in the tissue of the trauma patients. Cartilage: Thermal parameters revealed that structural change generated by pathologic conditions exceeded the effects of trauma. Bone: Thermal parameters from degenerative samples revealed more structural damage and calcification decrease than thermal parameters from trauma samples. Correlation: A statistically significant relationship between the extent of osteoarthritis and the thermal variables of cartilage and subchondral bone was discovered. Authors suggest that thermal analysis may be useful in the diagnostic process of orthopedic and posttraumatic shoulder diseases.

The Effect of Pulling Angle on Rotator Cuff Mechanical Properties in a Canine In Vitro Model.

The objective of this study was to examine the effect of pulling angle on time-zero mechanical properties of intact infraspinatus tendon or infraspinatus tendon repaired with the modified Mason-Allen technique in a canine model in vitro. Thirty-six canine shoulder samples were used. Twenty intact samples were randomly allocated into functional pull (135°) and anatomic pull (70°) groups (n = 10 per group). The remaining sixteen infraspinatus tendons were transected from the insertion and repaired using the modified Mason-Allen technique before being randomly allocated into functional pull or anatomic pull groups (n = 8 per group). Load to failure testing was performed on all specimens. The ultimate failure load and ultimate stress of the functional pulled intact tendons were significantly lower compared with anatomic pulled tendons (1310.2 ± 167.6 N vs. 1687.4 ± 228.2 N, p = 0.0005: 55.6 ± 8.4 MPa vs. 67.1 ± 13.3 MPa, p = 0.0334). For the tendons repaired with the modified Mason-Allen technique, no significant differences were observed in ultimate failure load, ultimate stress or stiffness between functional pull and anatomic pull groups. The variance of pulling angle had a significant influence on the biomechanical properties of the rotator cuff tendon in a canine shoulder model in vitro. Load to failure of the intact infraspinatus tendon was lower at the functional pulling position compared to the anatomic pulling position. This result indicates that uneven load distribution across tendon fibers under functional pull may predispose the tendon to tear. However, this mechanical character is not presented after rotator cuff repair using the modified Mason-Allen technique.

Musculoskeletal Modeling of the Compensatory Role of the Shoulder Muscles in Ensuring the Stability of the Shoulder Joint in the Conditions of Partial Traumatic Tear of the Supraspinatus Muscle Caused by Calcific Tendinitis

Relevance. The presence of calcium deposits in the rotator cuff tendons usually leads to a restriction of the biomechanics of the shoulder joint and, in particular, to a failure of the scapulohumeral rhythm. The question of the compensatory participation of the muscles of the shoulder girdle in ensuring the stability of the shoulder joint in conditions of partial-thickness damage to the tendon of the supraspinatus muscle caused by calcific tendinitis remains interesting and understudied.&#x0D; Objective: to carry out skeletal and muscular modeling with the study of the compensatory participation of the rotator cuff muscles in ensuring the stability of the shoulder joint during the elementary movement of elevation of the upper limb in conditions of partial-thickness damage to the supraspinatus tendon caused by the presence of calcification in it.&#x0D; Materials and Methods. For the analysis we used simulation modeling in the software package AnyBody Modeling System™ (AnyBody Technology A / S, Denmark) for Windows. The calculation was carried out using the software component Mannequin, selected from the AnyBody Managed Model Repository™ model collection. The parameters of joint forces acting in the direction of three axes – X, Y, Z – were calculated, where the X axis corresponded to the anterior-posterior force direction (antero-posterior force), the Y axis – to the inferior-superior force direction, the Z axis – compression-distraction force direction (medio-lateral force) on the shoulder joint. The object of the study was muscle activity (Activity) and muscle strength (Fm) of m. deltiodus clavicular, m. deltiodus scapularis, m. infrapsinatus, m. subscapularis, m. teres major, and m. teres minor while simulating a decrease in the strength of m. supraspinatus by 50% caused by the presence of calcification in the thickness of its tendon.&#x0D; Results. With complex movement of the upper limb, associated with the elevation of the upper limb, in conditions of partial-thickness tear to the m. supraspinatus, with a decrease in its strength by 50%, there is a compensatory increase in the strength of the muscles of the shoulder joint – the posterior portion of the m. deltoidus scapularis, m. infraspinatus and m. subscapularis, to ensure the stability of the shoulder joint. Taking into account minor changes in joint reactions along three axes, with a decrease in the strength of m. supraspinatus caused by the presence of calcification in its thickness, the compensatory mechanism of including additional muscle activity and muscle efforts of other muscles of the shoulder girdle provides the necessary stability of the shoulder joint in these conditions.&#x0D; Conclusions. The study confirms the possibility of successful application of programs of conservative treatment of calcifications of the m. supraspinatus tendon, aimed at developing the compensatory capabilities of the muscles of the shoulder girdle.

Comparison of rotator cuff to glenoid proximity based on scapulothoracic upward rotation classification

BackgroundRecent evidence suggests that internal impingement, or rotator cuff tendon deformation against the glenoid, occurs during overhead motions and may therefore be a mechanism of pathology even in non-athletes. Clinically, knowing how movement impacts potential injury mechanisms would be useful to guide movement-based treatment strategies. ObjectiveTo compare the distance between the glenoid and rotator cuff footprint between two groups classified based on scapulothoracic upward rotation (UR) magnitude (i.e., low, high) at 90° humerothoracic elevation. MethodsShoulder kinematics were quantified during scapular plane abduction in 60 participants using single-plane fluoroscopy. Of these, 40 were subsequently classified as having high or low scapulothoracic UR based on the sample's distribution. The minimum distance between the glenoid and rotator cuff footprint was calculated along with the locations of closest proximity (i.e., proximity centers). Minimum distances and proximity center locations were compared between groups using 2-factor mixed-model ANOVAs. The prevalence of glenoid-to-footprint contact was also compared. ResultsGlenoid-to-footprint distances consistently decreased as humerothoracic elevation angle increased, and the anterior aspect of the footprint was closest to the posterosuperior glenoid. Minimum distances were not significantly different between UR groups (p≥0.16). However, group differences existed in proximity center locations (p<0.01). Glenoid-to-footprint contact was identified in 75.0% of participants at an average (SD) of 133.6° (3.2°) humerothoracic elevation. ConclusionThe results of this study suggest that decreased UR as classified and assessed in this study does not significantly impact glenoid-to-footprint distances but does alter the location of the contact, which occurred in most participants.

Ultrasound Guided Arthroscopic Removal of Calcific Tendonitis: A Minimum of 2-Year Followup.

Background: We have developed a novel technique for managing rotator cuff calcific tendonitis, involving arthroscopic debridement of calcific tendonitis with localization assistance from a breast biopsy needle under ultrasound guidance. While we have demonstrated encouraging results at six-month follow-up, the medium-term outcomes and the long-term outcomes of this technique at 2 years or beyond are unknown. The aim of this paper was to determine if this technique was successful in resolving symptoms after two years and beyond. Study Design: Retrospective Cohort Study. Methods: Patients who underwent arthroscopic debridement of calcific tendonitis with localization assistance from a breast biopsy needle under ultrasound guidance by a senior surgeon were evaluated using patient-rated pain scores and functional status with the use of the Likert scales and via examiner-rated shoulder range-of-motion and strength at the pre-operative visit, at 1, 6, 12, and 24 weeks post-operatively, and long-term at a mean of 249 weeks after surgery. Results: At a mean follow-up period of 4.8 years (range, 2-10 years), 31 patients (33 shoulders) experienced significant improvement in the severity of pain at rest, with overhead activities, and during sleep compared to their pre-operative presentation (p < 0.001). The patient experienced less frequent pain during activities and sleep, and a decreased frequency of extreme pain (p < 0.001). Passive range of abduction (p = 0.003), forward flexion (p < 0.001), and supraspinatus strength (p = 0.018) improved compared to the presurgical presentation. Out of 27 patients, 24 patients (89%) had complete resolution of calcific tendonitis, and 26 patients (96%) had an intact rotator cuff. Conclusion: Arthroscopic debridement of calcific tendonitis with localization assistance from a breast biopsy needle under ultrasound guidance was very effective. Patients had significant pain relief, improved range of motion, and a reduction in stiffness at a mean post-operative period of 4.8 years. Patients had a significant reduction in residual calcification, and rotator cuff integrity was largely preserved by long-term follow-up. What is known about this subject: Calcific tendonitis of the rotator cuff is one of the most painful and debilitating disorders of the shoulder. This condition is characterized by the deposition of calcium-phosphate crystals within the rotator cuff tendons. Arthroscopic debridement and excision of rotator cuff calcifications have proven to be efficacious treatments with regards to clinical and functional outcomes in the short and medium term. Identifying the calcific lesion intra-operatively, however, can prove to be challenging. Furthermore, inadequate excision of the calcific deposit has been shown to have poorer clinical outcomes. We designed a technique that utilizes the assistance of ultrasound to guide a localization-biopsy wire to the calcific lesion. This technique aids in precisely identifying the location of the lesion intra-operatively to optimize accuracy in removing the maximum amount of calcific deposit possible. A short-term follow-up study by us has demonstrated successful outcomes with regards to the return of function and relief of pain. However, there have been no studies evaluating the effectiveness of this particular technique beyond six months. What this study adds to current knowledge: At a mean of 4.8 years, arthroscopic debridement of calcific tendonitis, using our technique, was successful in relieving the severity and frequency of pain with overhead activities, pain at rest, and pain during sleep, as well as improving range of motion.

Comparative study between double-row suture and modified Mason-Allen suture bridge in rotator cuff repair: a prospective clinical study

Background Rotator cuff lesions are one of the causes of shoulder pain. Surgical treatment has been increasingly indicated. Purpose The aim of this work is to compare the clinical outcome and tendon healing after arthroscopic rotator cuff repair either by modified Mason-Allen suture bridge technique or double-row suture stitch technique. Patients and methods During the period between August 2021 and July 2022, a prospective clinical study was conducted involving 20 patients with symptomatic rotator cuff tear, who underwent arthroscopic repair. These patients were managed by the modified Mason-Allen suture bridge technique and double-row suture. This study conducted in the Benha University Hospitals, Nasr City Insurance Hospital and the military production hospital. Results The current study revealed no statistically significant difference between groups according to demographic factors such as age, sex and side, with P value more than 0.05. There was statistically significant higher change in group A: modified Mason-Allen suture bridge compared with group B: double-row according to constant score, with P value less than 0.05 (significant). Conclusion This study proved that there is statistically significant difference between the modified Mason-Allen suture bridge technique versus double row in functional outcome and integrity of rotator cuff tendon healing with relative advantage to the modified Mason-Allen suture bridge technique.