Application of multidisciplinary team-based integrated traditional Chinese medicine and Western medicine in rotator cuff injury patients undergoing arthroscopic surgery.

BACKGROUND: Arthroscopic rotator cuff repair is a common surgical treatment for rotator cuff injuries (RCIs). Although this procedure has certain clinical advantages, it requires rehabilitation management interventions to ensure therapeutic efficacy. AIM: To investigate the effect of integrated traditional Chinese medicine and Western medicine (TCM-WM) under the multidisciplinary team (MDT) model on the postoperative recovery of patients undergoing arthroscopic surgery for RCIs. METHODS: This study enrolled 100 patients who underwent arthroscopic rotator cuff repair for RCIs at the Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine between June 2021 and May 2024. They were divided into a control group (n = 48) that received routine rehabilitation treatment and an experimental group (n = 52) that received TCM-WM under the MDT model (e.g., acupuncture, TCM traumatology and orthopedics, and rehabilitation). The results of the Constant-Murley Shoulder Score (CMS), Visual Analogue Scale (VAS), Shoulder Pain and Disability Index (SPADI), muscular strength evaluation, and shoulder range of motion (ROM) assessments were analyzed. RESULTS: After treatment, the experimental group showed significantly higher CMS scores in terms of pain, functional activity, shoulder joint mobility, and muscular strength than the baseline and those of the control group. The experimental group also exhibited significantly lower VAS and SPADI scores than the baseline and those of the control group. In addition, the experimental group showed significantly enhanced muscular strength (forward flexor and external and internal rotator muscles) and shoulder ROM (forward flexion, abduction, and lateral abduction) after treatment compared with the control group. CONCLUSION: TCM-WM under the MDT model improved shoulder joint function, relieved postoperative pain, promoted postoperative functional recovery, and facilitated the recovery of muscular strength and shoulder ROM in patients with RCIs who underwent arthroscopic rotator cuff repair.

Effect of Tear Size and Location on Supraspinatus Tendon Strain During Activities of Daily Living and Physiotherapy.

The supraspinatus tendon plays a crucial role in shoulder abduction, making it one of the common structures affected by injury. Clinically, crescent-shaped tears are the most commonly seen tear shape. By developing six specimen-specific, three-dimensional, supraspinatus-infraspinatus finite element model with heterogeneous material properties, this study aimed to examine the changes in tissue deformation (maximum principal strain) of the supraspinatus tendon due to specimen-specific material properties and rotator cuff tear size. FE models with small- and medium-sized full-thickness crescent-shaped tears were subjected to loads seen during activities of daily living and physiotherapy. Six fresh-frozen cadaveric shoulders were dissected to mechanically test the supraspinatus tendon and develop and validate FE models that can be used to assess changes in strain due to small (< 1 cm, equivalent to 20-30% of the tendon width) and medium-sized (1-3 cm, equivalent to 40-50% of the tendon width) tears that are located in the middle and posterior regions of the supraspinatus tendon. FE predictions of maximum principal strain at the tear tips were examined to determine whether failure strain was reached during activities of daily living (drinking and brushing teeth) and physiotherapy exercises (prone abduction and external rotation at 90° abduction). No significant differences were observed between the middle and posterior tear failure loads for small- and medium-sized tears. For prone abduction, there was a potential risk for tear progression (exceeded failure strain) for medium-sized tears in the supraspinatus tendon's middle and posterior regions. For external rotation at 90° abduction, one model with a middle tear and two with posterior tears experienced failure. For all daily activity loads, the strain never exceeded the failure strain. Our three-dimensional supraspinatus-infraspinatus FE model shows that small tears appear unlikely to progress based on the regional strain response; however, medium-sized tears are at higher risk during more strenuous physiotherapy exercises. Furthermore, differences in patient-specific tendon material properties are important in determining whether the tear will progress. Therefore, patient-specific management plans based on tear size may be beneficial to improve clinical outcomes.

Clinical effect of modified anterolateral acromioarthroplasty during arthroscopic rotator cuff repair.

BACKGROUND: This study aimed to compare the clinical effect of modified anterolateral and traditional acromioplasty in arthroscopic rotator cuff repair. METHODS: The clinical data of 92 patients with total rotator cuff tears admitted to the Department of Joint Surgery of Jinhua Central Hospital from January 2016 to December 2019 were retrospectively analyzed. Among them, 42 patients underwent traditional acromioplasty during arthroscopic rotator cuff repair, and 50 underwent modified anterolateral acromioplasty. Patients were evaluated for preoperative and postoperative shoulder function, pain and critical shoulder angle, and incidence of rotator cuff re-tear at 12 months postoperatively. RESULTS: The preoperative general data of patients in the classic and modified anterolateral acromioplasty groups did not differ significantly (P > 0.05) and were comparable. The UCLA, ASES, and Constant shoulder joint scores were significantly improved in both groups. The VAS score was significantly decreased at 12 months postoperative than preoperative, with a statistically significant difference (P ≤ 0.05). Shoulder function and pain scores did not differ significantly between the two groups at 12 months postoperatively (P > 0.05). The CSA did not differ significantly between preoperative and postoperative 12 months in the traditional acromioplasty group (P > 0.05). However, 12 months postoperative CSA in the modified anterolateral acromioplasty group was significantly smaller than the preoperative CSA, with a statistically significant difference (P ≤ 0.05). The rates of rotator cuff re-tears were 16.67% (7/42) and 4% (2/50) in the two groups at 12 months postoperatively, respectively, with statistically significant differences (P ≤ 0.05). CONCLUSIONS: Traditional and modified anterolateral acromioplasty while treating total rotator cuff tears using arthroscopic rotator cuff repair significantly improves shoulder joint function. However, modified anterolateral acromioplasty significantly reduced the CSA value and decreased the incidence of rotator cuff re-tears.

The Critical Shoulder Angle: A Significant Radiological Measure in Rotator Cuff vs. Glenohumeral Osteoarthritis in Chilean Patients-A Descriptive Cross-Sectional Study.

Background: Shoulder pain is one of the most important musculoskeletal conditions affecting the upper extremities. Glenohumeral osteoarthritis (GHOA) and rotator cuff injuries (RCIs) are notable for their high prevalence. The critical shoulder angle (CSA) is a significant radiological measure for determining the diagnosis and progression of patients with these conditions. Although there are reports in the international literature about this measure, in our country, guideline values considering these two pathologies are unknown. Objective: Our objective was to assess patients diagnosed with GHOA and RCI using an AP X-ray view and the CSA. Methods: To conduct this, we identified differences between sexes and age categories. Fifty-nine adult patients with GHOA and RCI were included. CSA grades varied depending on the age category and type of injury evaluated. Results: Significant differences between the age ranges of 40 and 54 (p = 0.05), 55-69 (p = 0.001), and 70-84 (p = 0.017) were observed. Conclusions: Patients with RCI tended to be younger and have a higher CSA compared to those with GHOA. It is important to have more normative values and to continue monitoring the critical shoulder angle in these patients.

Chronic Adaptation of Achilles Tendon Tissues upon Injury to Rotator Cuff Tendon in Hyperlipidemic Swine.

The biomechanical properties of the tendon are affected due to the changes in composition of the tendon extracellular matrix (ECM). Age, overuse, trauma and metabolic disorders are a few associated conditions that contribute to tendon abnormalities. Hyperlipidemia is one of the leading factors that contribute to the compromised biomechanical. Injury was made on infraspinatus tendon of hyperlipidemic swines. After 8 weeks (i) infraspinatus tendon from the injury site, (ii) infraspinatus tendon from the contralateral side and (iii) Achilles tendon, were collected and analyzed for ECM components that form the major part in biomechanical properties. Immunostaining of infraspinatus tendon on the injury site had higher staining collagen type-1 (COL1A1), biglycan, prolyl 4-hydroxylase and mohawk but lower staining for decorin than the control group. The Achilles tendon of the swines that had injury on infraspinatus tendon showed a chronic adaptation towards load which was evident from a more organized ECM with increased decorin, mohawk and decreased biglycan, scleraxis. The mechanism behind the collagen turnover and chronic adaptation to load need to be studied in detail with the biomechanical properties.

Comparison of functional outcomes following early and delayed arthroscopic repair for traumatic and non-traumatic rotator cuff injuries.

BACKGROUND: The effects of the timing of surgical repair on the outcomes of traumatic and non-traumatic rotator cuff injuries (RCI) remain elusive. Thus, this study aimed to compare differences in outcomes following the repair of traumatic and non-traumatic RCI at varying time points. METHODS: The study population comprised 87 patients with traumatic and non-traumatic RCI who underwent arthroscopic rotator cuff repair and were followed up for a minimum of 6 months. Next, the trauma and the non-trauma groups were stratified into subgroups according to the time of injury (early repair: occurring within 3 months; delayed repair: occurring after 3 months). Measurements before and after surgical interventions were compared to evaluate the effect of the duration of RCI on the functional status of patients in the trauma and non-trauma groups. Primary evaluation indices included the Visual Analog Scale (VAS) pain score, American Shoulder and Elbow Surgeons (ASES) score, Constant shoulder function score, and the University of California, Los Angeles (UCLA) shoulder score. Secondary evaluation indices consisted of shoulder range of motion (ROM), postoperative rotator cuff retear rate, and incidence of joint stiffness. RESULTS: Among the 40 patients in the trauma group, 22 underwent early repair, whereas the remaining 18 underwent delayed repair. In the non-trauma group consisting of 47 patients, 18 underwent early repair, whereas the remaining 29 underwent delayed repair. The minimum clinical follow-up time was 6 months, with an average follow-up time of 10.2 months. During postoperative follow-up, 1 and 6 patients who underwent early and delayed repair experienced re-tear in the trauma group, respectively. Contrastingly, 3 and 8 patients who underwent early and delayed repair presented with re-tear in the non-trauma group, respectively. CONCLUSION: Early repair of traumatic RCI yielded superior outcomes, including improved range of motion, lower pain symptoms, and lower risk of postoperative re-tears compared to delayed repair. Additionally, non-surgical treatment is recommended as the preferred approach for patients with non-traumatic RCI.

The effect of rehabilitation time on functional recovery after arthroscopic rotator cuff repair: a systematic review and meta-analysis.

Objective: We compared the effects of early and delayed rehabilitation on the function of patients after rotator cuff repair by meta-analysis to find effective interventions to promote the recovery of shoulder function. Methods: This meta-analysis was registered in PROSPERO (CRD42023466122). We manually searched the randomized controlled trials (RCTs) in the Cochrane Library, Pubmed, Cochrane Library, EMBASE, the China National Knowledge Infrastructure (CNKI), the China VIP Database (VIP), and the Wanfang Database to evaluate the effect of early and delayed rehabilitation after arthroscopic shoulder cuff surgery on the recovery of shoulder joint function. Review Manager 5.3 software was used to analyze the extracted data. Then, the PEDro scale was employed to appraise the methodological quality of the included research. Results: This research comprised nine RCTs and 830 patients with rotator cuff injuries. According to the findings of the meta-analysis, there was no discernible difference between the early rehabilitation group and the delayed rehabilitation group at six and twelve months after the surgery in terms of the VAS score, SST score, follow-up rotator cuff healing rate, and the rotator cuff retear rate at the final follow-up. There was no difference in the ASES score between the early and delayed rehabilitation groups six months after the operation. However, although the ASES score in the early rehabilitation group differed significantly from that in the delayed rehabilitation group twelve months after the operation, according to the analysis of the minimal clinically important difference (MCID), the results have no clinical significance. Conclusions: The improvement in shoulder function following arthroscopic rotator cuff surgery does not differ clinically between early and delayed rehabilitation. When implementing rehabilitation following rotator cuff repair, it is essential to consider the paradoxes surrounding shoulder range of motion and tendon anatomic healing. A program that allows for flexible progression based on the patient's ability to meet predetermined clinical goals or criteria may be a better option.

[Effects of Platelet-Rich Plasma-Derived Exosomes on Proliferation and Migration of Tendon Stem/Progenitor Cell].

Objective To investigate the effects of platelet-rich plasma-derived exosomes (PRP-Exos) on the proliferation and migration of tendon stem/progenitor cell (TSPC).Methods PRP-Exos were extracted through the combination of polymer-based precipitation and ultracentrifugation.The morphology,concentration,and particle size of PRP-Exos were identified by transmission electron microscopy and nanoparticle tracking analysis.The expression levels of surface marker proteins on PRP-Exos and platelet membrane glycoproteins were determined by Western blot analysis.Rat TSPC was extracted and cultured,and the expression of surface marker molecules on TSPC was detected using flow cytometry and immunofluorescence staining.The proliferation of TSPC influenced by PRP-Exos was evaluated using CCK-8 assay and EdU assay.The effect of PRP-Exos on the migration of TSPC was evaluated by cell scratch assay and Transwell assay.Results The extracted PRP-Exos exhibit typical saucer-like structures,with a concentration of 4.9×1011 particles/mL,an average particle size of (132.2±56.8) nm,and surface expression of CD9,CD63 and CD41.The extracted TSPC expressed the CD44 protein.PRP-Exos can be taken up by TSPC,and after co-cultured for 48 h,concentrations of 50 and 100 µg/mL of PRP-Exos significantly promoted the proliferation of TSPC (both P<0.001),with no statistical difference between the two concentrations (P=0.283).Additionally,after co-cultured for 24 h,50 µg/mL of PRP-Exos significantly promoted the migration of TSPC (P<0.001).Conclusion Under in vitro culture conditions,PRP-Exos significantly promote the proliferation and migration of rat TSPC.

Rapamycin facilitates healing of the tendon-bone interface in an aging rat model of chronic rotator cuff injury.

BACKGROUND: Tendon-bone interface (TBI) healing in chronic rotator cuff injury (CRCI) in older individuals is a common clinical challenge due to cellular senescence, as well as decreased tissue repair and regeneration. Many studies have demonstrated the antiaging, improved tissue repair, and bone regeneration properties of rapamycin (RPM) in multiple age-related diseases. This study aimed to explore the effects of RPM on TBI healing after CRCI in an aging rat model. METHODS: A CRCI model was established in 60 Sprague-Dawley rats (24 months old). Rats were then randomly allocated into the control, 0.1 µg RPM, and 1 µg RPM groups. At 4 and 8 weeks postreconstructive surgery, the supraspinatus tendon-humerus complexes were harvested for biomechanical, microimaging, histological, and immunohistochemical evaluations. RESULTS: Biomechanical testing results demonstrated that the failure load, ultimate strength, and stiffness of the 2 RPM groups were significantly higher than those of the control group at 4 and 8 weeks postoperatively. Microradiographically, both RPM groups had significantly higher values of bone mineral density and the ratio of trabecular bone volume to total volume than controls at each time point. Moreover, the RPM groups had higher histological scores and showed better regenerated TBI, characterized by better organizational tissue, more fibrocartilage cells, and more bone formation. Immunohistochemical evaluations showed that RUNX2-, SOX9-, and SCX-positive cells were significantly more in the 2 RPM groups than in the controls at each time point. CONCLUSIONS: RPM may effectively enhance CRCI healing after reconstruction by facilitating osteogenesis, tenogenesis, and fibrocartilage reformation at the TBI, as well as improving biomechanical properties.

Experimental Study of Autologous Platelet-rich Plasma Combined With Sodium Hyaluronate on Tendon-bone Healing After Rotator Cuff Injury Repair in Rabbits.

OBJECTIVE: To investigate the therapeutic effects of autologous platelet-rich plasma (PRP) combined with sodium hyaluronate on tendon healing following rotator cuff injury repair in rabbits. METHODS: New Zealand white rabbits were randomly assigned to five groups: sham operation group, control group, PRP group, sodium hyaluronate group, and combined group, each comprising 12 rabbits. A rotator cuff injury model was established in all groups except the sham operation group. At 8 weeks post-surgery, 12 lateral rotator cuff specimens were taken from each group. Four specimens were randomly selected from each group for biomechanical testing, and analyses were conducted on the expression of vascular endothelial growth factor (VEGF), the fiber area ratio of COL-I and COL-III, and tissue morphology. RESULTS: The combined group exhibited the highest biomechanical strength in the cuff tissue of white rabbits (P < 0.05). There was no significant difference in VEGF levels among the five groups (F = 0.814, P = 0.523). However, a significant difference was observed in the ratio of fiber area between COL-I and COL-III groups (F = 11.600, P < 0.001), with the combined group scoring the highest (3.82 ± 0.47 minutes). The inflammatory infiltration in tendon-bone tissue was minimal, and histological morphology was optimal. CONCLUSION: The combination of PRP and sodium hyaluronate effectively promotes the repair of rotator cuff injuries and accelerates tendon-bone healing.

Efficacy comparison between acupuncture and other modalities in the treatment of rotator cuff diseases: meta-analysis of randomized controlled trials.

OBJECTIVE: This study aimed to analyze the efficacy of acupuncture alone or combined with physical therapy compared to other treatment interventions for relieving pain and improving function in rotator cuff diseases. METHODS: Our study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. After PROSPERO (CRD42023396740) registration, all randomized controlled trials (RCTs) published from the inception of the databases to October 10, 2023, evaluating the efficacy of acupuncture either alone or in combination with physical therapy for treating rotator cuff diseases, were extracted from seven databases, including PubMed, Embase, the Web of Science, the Cochrane Library, the China National Knowledge Infrastructure (CNKI), the VIP Database for Chinese Technical Periodicals (VIP), and the Wanfang Date. Two independent researchers assessed the quality of the included studies and extracted relevant data. Furthermore, a meta-analysis was conducted using Stata 14 software. RESULTS: We included 13 RCTs - 12 published in English and 1 in Chinese - that enrolled 1,371 patients. The meta-analysis results demonstrated that acupuncture alone or in combination with physical therapy was superior to other interventions for short-term shoulder joint function improvement (standardized mean difference [SMD] = -0.82, 95% confidence interval [95% CI]: -1.28 to -0.35, P = 0.001), medium-term shoulder joint function improvement (SMD = -1.00, 95% CI: -1.62 to -0.38, P = 0.002), short-term pain relief (weighted mean difference [WMD] = -1.37, 95% CI: -2.39 to -0.38, P = 0.006), medium-term pain relief (WMD = -1.66, 95% CI: -2.70 to -0.63, P = 0.002), and post-treatment shoulder joint abduction improvements (SMD = 0.68, 95% CI: 0.20 to 1.16, P = 0.005), external rotation (SMD = 0.62, 95% CI: 0.13 to 1.11, P = 0.012), and forward flexion (SMD = 0.71, 95% CI: 0.44 to 0.97, P < 0.001), with significant differences (P < 0.05). CONCLUSION: Based on the current clinical data, meta-analysis showed that acupuncture alone or combined with physical therapy is efficacious for short- and medium-term (< 3 months) pain relief and functional improvements. However, compared to other interventions, the efficacy of the long-term (3 to 12 months) period did not significantly differ. After treatment, these modalities displayed advantages such as improved shoulder joint abduction, external rotation, and forward flexion movements. However, no significant difference was noted in internal rotation movement. Thus, future studies might further investigate whether different acupuncture methods affect the efficacy of treating rotator cuff diseases and improving long-term outcome.

Analgesic effect and safety of a half-dose transdermal buprenorphine patch after arthroscopic rotator cuff repair.

Objective: To retrospectively explore the effect of a half-dose buprenorphine transdermal patch for analgesia after arthroscopic rotator cuff repair (ARCR). Methods: This analysis was performed with clinical data from patients who received unilateral ARCR in our hospital between October 2017 and December 2020. The patients were divided into three groups (30 cases each). In group A (control group), 100 mg flurbiprofen axetil (FA) was administered twice a day for 5 days after surgery. In group B (experimental group), 100 mg FA was administered twice a day for 5 days and half (2.5 mg) of a buprenorphine transdermal patch was applied after surgery; an additional half (2.5 mg) patch was applied 3 days later. In group C (condition control group), 100 mg FA was administered twice a day for 5 days and a 5-mg patch was applied directly after surgery. The visual analog scale (VAS) was administered repeatedly 1 day before surgery and 1, 2, 3, 5, and 14 days after surgery in each group. The simple shoulder test (SST) score, range of shoulder forward elevation (FE), and external rotation (ER) were recorded preoperatively and 12 weeks postoperatively. Results: VAS scores on postoperative days 3 and 5 were significantly lower in groups B and C than in group A (p < 0.05). The VAS score on postoperative day 14 was significantly lower in group C than in group A (p < 0.05). The difference in VAS score between groups B and C was not significant (p > 0.05). All patients had significantly improved VAS scores, SST scores, FE, and ER at 12 weeks postoperatively. Conclusion: The half-dose buprenorphine transdermal patch had a good analgesic effect with minimal side effects after ARCR and did not delay the recovery of shoulder joint function.

Research Progress of TCM Therapy for Rotator Cuff Injury.

Rotator cuff injury is a common orthopedic disease with high morbidity, which is one of the most important reasons for shoulder pain and limited movement. With the development of more research, the Traditional Chinese Medicine (TCM) therapy for rotator cuff injury is increasingly rich and has achieved a good curative effect. TCM has certain characteristics and advantages, which may become the main development trend of the treatment. By consulting the relevant literature on TCM therapy for rotator cuff injury in recent years, we found that commonly used TCM therapy include Chinese herbal therapy, Chinese herbal compounds, External treatment of Chinese herbal therapy, Acupuncture therapy, Floating needle therapy，Massage therapy, and others, which make a great clinical effect. This paper summarizes and analyzes the common TCM therapy of the rotator cuff injury, to provide new ideas for the selection of clinical treatment options.

Outcome of arthroscopic triple release combined with rotator cuff repair in the treatment of rotator cuff injury combined with frozen shoulder.

Objective: To investigate the effect of arthroscopic triple release combined with rotator cuff repair in the treatment of rotator cuff injury combined with frozen shoulder and its influence on the range of motion and pain score of shoulder joint, and the levels of serum pain mediators. Methods: This was prospective study. A total of 132 patients with rotator cuff injury combined with frozen shoulder admitted to The Third Affiliated Hospital of Gansu University of Traditional Chinese Medicine from December 2020 to December 2022 were prospectively selected and divided into two groups according to the random number table method: control group (n=67) and observation group (n=65). Patients in the control group were treated with arthroscopic rotator cuff repair alone, while those in the observation group were treated with arthroscopic triple release combined with rotator cuff repair, and the surgical effects of the two groups were compared. Results: Three months after treatment, the external rotation, internal rotation, abduction, forward flexion, ß-endorphin(ß-EP), prostagranin E2 (PGE2) and substance P(SP)in the observation group were better than those in the control group (P<0.05), while the weight-bearing strength of the affected limb in internal rotation, external rotation and forward flexion was higher than that of the control group(P<0.05). Meanwhile, the Visual Analogue Scale (VAS) score of the observation group was lower than that of the control group at one month and three months after treatment, while the University of California at Los Angeles shoulder rating scale (UCLA) score and Constant-Murley Score (CMS) were higher than those of the control group (P< 0.05). Conclusion: Arthroscopic triple release combined with rotator cuff repair improves various effects for patients with rotator cuff injury combined with frozen shoulder, such as ameliorating the muscle strength of the affected limb and improving the level of pain mediators.

Effect of Platelet-Rich Plasma at Different Initiation Times on Healing of the Bone-Tendon Interface of the Rotator Cuff in a Mouse Model.

Background: Platelet-rich plasma (PRP) has demonstrated beneficial effects on healing of the bone-tendon interface (BTI). Purpose: To determine the optimal initiation time for PRP application after rotator cuff repair in an animal model. Study Design: Controlled laboratory study. Methods: A total of 136 C57BL/6 mice were included; 40 mice were used to prepare PRP, while 96 mice underwent acute supraspinatus tendon (SST) repair. The animals were randomly divided into 4 groups: a control group and 3 groups in which PRP was injected into the injury interface immediately after surgery, on the 7th postoperative day (PRP-7d), and on the 14th postoperative day. At 4 and 8 weeks postoperatively, the animals were sacrificed, blood was collected by eyeball removal, and samples of the SST-humerus complex were collected. Histological, imaging, immunological, and biomechanical data were compared among the groups using 1-way analysis of variance with the Bonferroni post hoc test. Results: Histological analysis revealed that the fibrocartilage layer at the BTI was larger in the PRP-7d group compared to the other groups at both 4 and 8 weeks postoperatively. Moreover, the PRP-7d group exhibited improved proteoglycan content and distribution compared to the other groups. Enzyme-linked immunosorbent assay results demonstrated that at 4 weeks postoperatively, higher concentrations of transforming growth factor-ß1 and platelet-derived growth factor-BB (PDGF-BB) were seen in the PRP-7d group versus the PRP-14d and control gruops (P < .05), and at 8 weeks postoperatively, the concentration of PDGF-BB was higher in the PRP-7d group versus the control group (P < .05). Biomechanical testing at 4 weeks postoperatively revealed that the failure load and ultimate strength of the SST-humerus complex were superior in the PRP-7d group compared to the other groups (P < .05), at 8 weeks, PRP-7d group was superior to the control group (P < .05). Additionally, at 8 weeks postoperatively, the PRP-7d group exhibited a greater trabecular number and trabecular thickness at the BTI compared to the PRP-14d and control gruops (P < .05). Conclusion: PRP promoted healing of the BTI after a rotator cuff injury at an early stage. Clinical Relevance: A PRP injection on the 7th postoperative day demonstrated superior therapeutic effects compared with injections at other time points.

Serial Changes of Fatty Degeneration and Clinical Outcomes after Repair of Medium-Sized Rotator Cuff Tears.

Background: This study was designed to longitudinally analyze quantitative intramuscular and perimuscular fat and evaluate clinical outcomes according to healing degree after rotator cuff repair. Methods: From June 2013 through October 2018, patients who had undergone repair due to medium-sized rotator cuff tears and serial chest computed tomography (CT) preoperatively and at early (6-12 months) and late (at least 3 years) postoperative follow-ups were included. Supraspinatus (SST) intramuscular fat fraction ratio (IFFR) and perimuscular fat fraction ratio (PFFR) were calculated using chest CT. The rotator cuff integrity was categorized as healed, smaller retear (SRT), and larger retear (LRT) by comparing the preoperative tear size and retear size in shoulder CT arthrography at postoperative follow-ups. Clinical outcomes were evaluated using the American Shoulder and Elbow Surgeons (ASES) score, the University of California at Los Angeles (UCLA) shoulder rating scale, and the Constant score preoperatively and at early and late postoperative follow-ups. Results: In the LRT group, compared with the preoperative values, there were increases in the SST IFFR and PFFR at the early (p = 0.002 and p = 0.006, respectively) and late (p < 0.001 and p < 0.001, respectively) postoperative time points. Late postoperative clinical scores (UCLA and Constant scores) were not improved compared to preoperative scores (p = 0.156 and p = 0.094, respectively). In the SRT group, there was no difference in the mean SST IFFR and PFFR between preoperative and early postoperative time points (p = 0.766 and p = 0.180, respectively), but the late postoperative values were higher than preoperative values (p = 0.009 and p = 0.049, respectively). Late postoperative clinical scores (ASES, UCLA, and Constant scores) in the SRT group improved compared to preoperative time (p < 0.001, p < 0.001, and p = 0.016, respectively). In the healed group, compared with the preoperative values, there was no difference in the mean SST IFFR and PFFR at postoperative time points; however, the late postoperative clinical scores (ASES, UCLA, and Constant scores) were improved (all p < 0.001). Conclusions: In the SRT group, IFFR and PFFR progressed in the late postoperative period and clinical scores improved over time. However, in the LRT group, IFFR and PFFR progressed in the early and late postoperative periods and clinical scores did not improve at the late postoperative follow-up.

Human umbilical cord mesenchymal stem cells overexpressing RUNX1 promote tendon-bone healing by inhibiting osteolysis, enhancing osteogenesis and promoting angiogenesis.

BACKGROUND: Rotator cuff injury (RCI) is a common shoulder injury, which is difficult to be completely repaired by surgery. Hence, new strategies are needed to promote the healing of tendon-bone. OBJECTIVE: We aimed to investigate the effect of human umbilical cord mesenchymal stem cells (hUC-MSCs) overexpressing RUNX1 on the tendon-bone healing after RCI, and to further explore its mechanism. METHODS: Lentiviral vector was used to mediate the overexpression of RUNX1. RUNX1-overexpressed UCB-MSCs (referred to as MSC-RUNX1) were co-cultured with osteoclasts, and TRAP staining was performed to observe the formation of osteoclasts. Then MSC-RUNX1 was cultured in osteogenic differentiation medium, Alizarin red staining was conducted to detect osteogenic differentiation. The expression of markers of osteogenesis and osteoclast was detected by RT-qPCR. EA. hy926 cells were co-cultured with MSC-RUNX1. Transwell assay was used to detect the migration, and the expression of angiogenesis related-genes VEGF and TGF-ß was detected by RT-qPCR. The rat rotator cuff reconstruction model was established and MSCs were injected at the tendon-bone junction. Biomechanical test and micro-CT scanning were performed, and HE, Masson and Alcian Blue staining were used for histological evaluation of tendon-bone healing. TUNEL and PCNA immunofluorescence (IF) staining were performed to evaluate apoptosis and proliferation at the tendon-bone healing site. The levels of TNF-α, IL-6 and IL-8 in serum were detected by ELISA. The expression of CD31 and Endomucin that related to angiogenesis was detected by IF. Safranin O-fast and TRAP/CD40L immunohistochemical staining were used to assess the levels of osteoclasts and osteoblasts at the tendon-bone healing site. RESULTS: hUC-MSCs overexpressing RUNX1 inhibited osteoclast formation and promoted osteogenic differentiation. MSC-RUNX1 could promote the migration and tube formation of EA. hy926 cells, and up-regulate the levels of VEGF and TGF-ß. Model mice treated with MSC-RUNX1 partially restored the biomechanical indexes. Treatment of MSC-RUNX1 obviously increased the bone density, accompanied by the formation of new bone. In vivo experiments showed that MSC-RUNX1 treatment could promote tendon-bone healing and inhibit inflammatory response in rats. MSC-RUNX1 treatment also promoted angiogenesis at the tendon-bone healing site, while inhibiting osteoclast formation and promoting osteogenic differentiation. CONCLUSION: hUC-MSCs overexpressing RUNX1 can inhibit the formation of osteoclasts and differentiation of osteoblasts, promote angiogenesis and inhibit inflammation, thereby promoting tendon-bone healing after RCI.

[Pro-oxidation status of rotator cuff tissue and expression of Beclin-1 and mTOR in patients with rotator cuff injury].

OBJECTIVE: To explore pro-oxidative state of rotator cuff tissue and expression levels of Beclin-1 and mam-malian target of rapamycin(mTOR) in patients with acute and chronic rotator cuff injury, and then analyzed relationship between rotator cuff injury and oxidative stress and autophagy. METHODS: Forty patients with rotator cuff injury were seleceted from July 2019 to December 2020, and divided into male chronic injury group, male acute injury group, female chronic injury group, and female acute injury group, 10 patients in each group. All patients were performed rotator cuff repair under arthroscopy. The sample of tendon at the rotator cuff injury site of the patient was taken during operation, and total reactive oxygen species (ROS) and superoxide dismutase(SOD) were detected by detection kit;expression of Beclin-1 and mTOR mRNA were detected by reverse transcription-polymerase chain reaction (RT-PCR), and Western-blot was applied to detect protein expression of Beclin-1 and p-mTOR/mTOR. RESULTS: There were no significant difference in expression of ROS, SOD, Beclin-1mRNA and mTOR mRNA between male and female chronic injury groups, and between male and female acute injury groups (P>0.05); ROS, SOD and Beclin-1mRNA in male chronic injury group were higher than those in male chronic injury group, while mTOR mRNAand protein decreased (P<0.05);ROS, SOD and Beclin-1 mRNA in female chronic injury group were up-regulated compared with female acute injury group, while mTOR mRNA was down-regulated (P<0.05). CONCLUSION: Chronic rotator cuff injury is more likely to stimulate the pro-oxidation state of rotator cuff tissue than acute rotator cuff injury, which could up-regulating expression of autophagy factor Beclin-1 and down-regulating expression of mTOR. Therefore, patients with chronic rotator cuff injury may have higher levels of oxidative stress and autophagy.

Progress in studying the impact of hyperlipidemia and statins on rotator cuff injury and repair.

This review delves into the intersection of two prevalent conditions, hyperlipidemia and rotator cuff injuries, both of which bear substantial healthcare burdens. Our investigation begins with an exploration of rotator cuff injuries, common musculoskeletal disorders that severely impair shoulder functionality and quality of life. These injuries are notably pervasive among sports enthusiasts and the older adult, with an incidence rate estimated at 5-10% in the general population. Despite their widespread occurrence and the diverse, multifactorial etiological factors, effective treatment strategies remain elusive. We then examine hyperlipidemia, a metabolic disorder affecting approximately 40% of the global adult population. Characterized by elevated levels of cholesterol and triglycerides, hyperlipidemia can precipitate severe cardiovascular complications and presents a significant socioeconomic burden. Although current management strategies encompass lifestyle modifications and pharmacological interventions, the condition remains a formidable health challenge. Central to this review is the exploration of a potential association between hyperlipidemia and rotator cuff injuries. We aim to synthesize the current understanding of hyperlipidemia's role in the pathophysiology of rotator cuff injuries, thereby offering fresh insights into their common etiological underpinnings, potential therapeutic targets, and drugs, such as Statins. The influence of other lipid-lowering therapeutics on tendon health is also considered, and further research into the molecular pathways and potential therapeutic benefits of these drugs is required. This pursuit aligns with broader efforts to enhance patient outcomes, minimize healthcare burdens, and contribute to the global understanding of these prevalent conditions.

Polarized macrophages regulate fibro/adipogenic progenitor (FAP) adipogenesis through exosomes.

BACKGROUND: Macrophage polarization has been observed in the process of muscle injuries including rotator cuff (RC) muscle atrophy and fatty infiltration after large tendon tears. In our previous study, we showed that fibrogenesis and white adipogenesis of muscle residential fibro/adipogenic progenitors (FAPs) cause fibrosis and fatty infiltration and that brown/beige adipogenesis of FAPs promotes rotator cuff muscle regeneration. However, how polarized macrophages and their exosomes regulate FAP differentiation remains unknown. METHODS: We cultured FAPs with M0, M1, and M2 macrophages or 2 × 109 exosomes derived from M0, M1 and M2 with and without GW4869, an exosome inhibitor. In vivo, M0, M1, and M2 macrophages were transplanted or purified macrophage exosomes (M0, M1, M2) were injected into supraspinatus muscle (SS) after massive tendon tears in mice (n = 6). SS were harvested at six weeks after surgery to evaluate the level of muscle atrophy and fatty infiltration. RESULTS: Our results showed that M2 rather than M0 or M1 macrophages stimulates brown/beige fat differentiation of FAPs. However, the effect of GW4869, the exosome inhibitor, diminished this effect. M2 exosomes also promoted FAP Beige differentiation in vitro. The transplantation of M2 macrophages reduced supraspinatus muscle atrophy and fatty infiltration. In vivo injections of M2 exosomes significantly reduced muscle atrophy and fatty infiltration in supraspinatus muscle. CONCLUSION: Results from our study demonstrated that polarized macrophages directly regulated FAP differentiation through their exosomes and M2 macrophage-derived exosomes may serve as a novel treatment option for RC muscle atrophy and fatty infiltration.