A Hyperglycemic Microenvironment Inhibits Tendon-to-Bone Healing through the let-7b-5p/CFTR Pathway.

BACKGROUND: Tendon-to-bone healing is a difficult process in treatment of rotator cuff tear (RCT). In addition, diabetes is an important risk factor for poor tendon-to-bone healing. Therefore, we investigated the specific mechanisms through which diabetes affects tendon-to-bone healing by regulating the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR). METHODS: Tendon-derived stem cells (TDSCs) were extracted from rats after which their proliferative capacities were evaluated by the MTT assay. The expression levels of CFTR and tendon-related markers were determined by qRT-PCR. Then, bioinformatics analyses and dual luciferase reporter gene assays were used to identify miRNAs with the ability to bind CFTR mRNA. Finally, CFTR was overexpressed in TDSCs to validate the specific mechanisms through which the high glucose microenvironment inhibits tendon-to-bone healing. RESULTS: The high glucose microenvironment downregulated mRNA expression levels of tendon-related markers and CFTR in TDSCs cultured with different glucose concentrations. Additionally, bioinformatics analyses revealed that let-7b-5p may be regulated by the high glucose microenvironment and can regulate CFTR levels. Moreover, a dual luciferase reporter gene assay was used to confirm that let-7b-5p targets and binds CFTR mRNA. Additional experiments also confirmed that overexpressed CFTR effectively reversed the negative effects of the hyperglycaemic microenvironment and upregulation of let-7b-5p on TDSC proliferation and differentiation. These findings imply that the hyperglycemic microenvironment inhibits CFTR transcription and, consequently, proliferation and differentiation of TDSCs in vitro by upregulating let-7b-5p. CONCLUSIONS: A hyperglycemic microenvironment inhibits TDSC proliferation in vitro via the let-7b-5p/CFTR pathway, and this is a potential mechanism in diabetes-induced poor tendon-to-bone healing.

Incidence and risk factors for early postoperative stiffness after arthroscopic rotator cuff repair in patients without preoperative stiffness.

The purpose of this study was to investigate the incidence and risk factors of early postoperative stiffness in patients without preoperative stiffness undergoing isolated arthroscopic rotator cuff repair (ARCR). Two hundred seventy-four patients who underwent primary ARCR were included. At 3 months after surgery, criteria for shoulder stiffness was set as follows: (1) passive forward flexion < 120˚, or (2) external rotation at side < 30˚. Patients with preoperative stiffness or who underwent additional procedures were excluded. Patients-related, radiological (muscle atrophy and fatty infiltration), and intraoperative (tear size, repair techniques, number of anchors used, and synovitis scores) risk factors were analyzed. Univariate and multivariate analyses were used to identify risk factors for postoperative stiffness. Thirty-nine of 274 patients (14.2%) who underwent ARCR developed postoperative stiffness. Univariate analyses revealed that early postoperative stiffness was significantly associated with diabetes mellitus (p = 0.030). However, radiological and intraoperative factors did not affect postoperative shoulder stiffness (all p > 0.05). Multivariate analyses revealed early postoperative stiffness was significantly associated with diabetes mellitus and timing of rehabilitation (p = 0.024, p = 0.033, respectively). The overall incidence of early postoperative stiffness following isolated ARCR in patients without preoperative stiffness was 14.2%. Diabetes mellitus and timing of rehabilitation were independent risk factors for early postoperative stiffness following ARCR.

Improved biomechanics in experimental chronic rotator cuff repair after shockwaves is not reflected by bone microarchitecture.

PURPOSE: The aim of this study was to investigate the effect of extracorporeal shockwave therapy (ESWT) on bone microstructure as well as the bone-tendon-interface and the musculo-tendinous transition zone to explain the previously shown improved biomechanics in a degenerative rotator cuff tear animal model. This study hypothesized that biomechanical improvements related to ESWT are a result of improved bone microstructure and muscle tendon properties. METHODS: In this controlled laboratory study unilateral supraspinatus (SSP) tendon detachment was performed in 48 male Sprague-Dawley rats. After a degeneration period of three weeks, SSP tendon was reconstructed transosseously. Rats were randomly assigned into three groups (n = 16 per group): control (noSW); intraoperative shockwave treatment (IntraSW); intra- and postoperative shockwave treatment (IntraPostSW). Eight weeks after SSP repair, all rats were sacrificed and underwent bone microstructure analysis as well as histological and immunohistochemical analyses. RESULTS: With exception of cortical porosity at the tendon area, bone microstructure analyses revealed no significant differences between the three study groups regarding cortical and trabecular bone parameters. Cortical Porosity at the Tendon Area was lowest in the IntraPostSW (p≤0.05) group. Histological analyses showed well-regenerated muscle and tendon structures in all groups. Immunohistochemistry detected augmented angiogenesis at the musculo-tendinous transition zone in both shockwave groups indicated by CD31 positive stained blood vessels. CONCLUSION: In conclusion, bone microarchitecture changes are not responsible for previously described improved biomechanical results after shockwave treatment in rotator cuff repair in rodents. Immunohistochemical analysis showed neovascularization at the musculo-tendinous transition zone within ESWT-treated animals. Further studies focusing on neovascularization at the musculo-tendinous transition zone are necessary to explain the enhanced biomechanical and functional properties observed previously. CLINICAL RELEVANCE: In patients treated with a double-row SSP tendon repair, an improvement in healing through ESWT, especially in this area, could prevent a failure of the medial row, which is considered a constantly observed tear pattern.

What Factors Are Associated with Symptomatic Rotator Cuff Tears: A Meta-analysis.

BACKGROUND: Rotator cuff tears are common. A previous systematic review reported on factors associated with rotator cuff tears; however, it included relatively few studies and few variables, and in addition, it had considerable heterogeneity. To identify the factors associated with symptomatic rotator cuff tears and to help guide clinicians to potentially modifiable factors, we felt a broader and more inclusive meta-analysis would be useful. QUESTIONS/PURPOSES: In this systematic review and meta-analysis, we asked what (1) demographic, (2) disease, and (3) imaging factors are associated with symptomatic rotator cuff tears? METHODS: PubMed, Embase, and Web of Science were searched, and the search period were from the inception of each database through February 2021. The keywords included "risk factor," "rotator cuff injury," "rotator cuff tears," and "rotator cuff tendinitis." All comparative studies on symptomatic rotator cuff tears were included. We considered that the diagnosis of rotator cuff tear could be made by any imaging tool (MRI or ultrasound). We considered either partial- or full-thickness tears to be a rotator cuff tear. No language restrictions were applied. Twenty-six articles from 14 countries involving 9809 individuals, consisting of 3164 patients and 6645 controls, were included. The Newcastle-Ottawa Scale and the Agency for Healthcare Research and Quality (AHRQ) scale were used to evaluate the risk of bias of the included studies, and the highest scores were 9 and 11, respectively. The Newcastle-Ottawa Scale was used for retrospective comparative studies, and the AHRQ was used to evaluate prospective comparative studies. The eight retrospective comparative studies we included were scored from 4 to 9. The quality score of the 18 prospective comparative studies ranged from 6 to 9. Publication bias was explored using the Egger test. Heterogeneity was estimated using the I2 value. If there was no heterogeneity (I2 ≤ 50%), a fixed-effects model was used to determine the overall effect size; if there was heterogeneity (I2 > 50%), a random-effects model was used to merge the effect values. A meta-analysis was performed with RevMan 5.3, and the risk ratio (RR) and weighted mean difference of related factors were calculated. RESULTS: Our meta-analysis identified the following demographic factors associated with an increased risk of rotator cuff tears: older age (mean difference 3.1 [95% CI 1.4 to 4.8]; p < 0.001), greater BMI (mean difference 0.77 [95% CI 0.37 to 1.17]; p < 0.001), smoking (RR 1.32 [95% CI 1.17 to 1.49]; p < 0.001), dominant arm (RR 1.15 [95% CI 1.06 to 1.24]; p < 0.001), greater height (mean difference 0.9 [95% CI 0.4 to 1.4]; p < 0.001), and heavier weight (mean difference 2.24 [95% CI 0.82 to 3.66]; p = 0.002). Regarding disease factors, we found that traumatic events (RR 1.91 [95% CI 1.40 to 2.54]; p < 0.001) and hypertension (RR 1.50 [95% CI 1.32 to 1.70]; p < 0.001) were associated with symptomatic rotator cuff tears. Regarding imaging factors, we found that the following three factors were associated with symptomatic rotator cuff tears: greater acromion index (mean difference 0.11 [95% CI 0.06 to 0.16]; p < 0.001), greater critical shoulder angle (mean difference 1.9 [95% CI 1.5 to 2.3]; p < 0.001), and smaller glenoid version angle (mean difference -1.3 [95% CI -1.9 to -0.8]; p < 0.001). We found no association between the patient's sex or the presence or absence of thyroid disease and the likelihood of a rotator cuff tear being present. CONCLUSION: This study identified several factors associated with symptomatic rotator cuff tears, including blood glucose, blood pressure, weight, and smoking. Clinicians may seek to modify these factors, possibly in patients with symptomatic rotator cuff tears, but also in symptomatic patients who have not yet been diagnosed with rotator cuff tears because there would be no harm or risk associated with modifying any of the factors we identified. Future research should further study whether addressing these factors can delay the progression and size of rotator cuff tears.Level of Evidence Level III, prognostic study.

Injection of Micronized Human Amnion/Chorion Membrane Results in Increased Early Supraspinatus Muscle Regeneration in a Chronic Model of Rotator Cuff Tear.

Surgical repair of severe rotator cuff tear often results in retear due to unaddressed muscle degeneration. The objective of this study was to test the regenerative potential of micronized dehydrated Human Amnion/Chorion Membrane (dHACM), in a clinically relevant delayed reattachment model of rotator cuff repair. Micronized dHACM was injected into rat supraspinatus muscle during tendon re-attachment surgery, three weeks after original tendon injury. One week after material injection, inflammatory and mesenchymal stem cell infiltration into supraspinatus muscles was assessed via flow cytometry. Histological methods were utilized to assess structural and regenerative changes in muscle one and three weeks after material injection. Micronized dHACM injection resulted in increased M1-like macrophages (17.1 [Formula: see text] fold change over contralateral controls) and regenerating muscle fibers (4.3% vs 1.7% in saline treated muscles) one week after injection compared to saline treated muscles. Tendon reattachment itself exhibited intrinsic healing in this model, demonstrated by a general return of muscle weight and reduced fibrosis. Our results indicate that injection of micronized dHACM may initiate an inflammatory response in degenerated muscle that promotes early muscle regeneration, and that our animal model may be a suitable platform for studying treatments in muscle at early timepoints, before intrinsic healing occurs.

Stress distribution pattern in the distal radioulnar joint before and after ulnar shortening osteotomy in patients with ulnar impaction syndrome.

Ulnar shortening osteotomy (USO) for ulnar impaction syndrome potentially leads to degenerative changes of the distal radioulnar joint (DRUJ). This study was performed to evaluate the effect of the sigmoid notch morphology on the stress distribution pattern of the DRUJ using computed tomography (CT) osteoabsorptiometry (CT-OAM). We reviewed the pre- and postoperative transverse CT images of 15 wrists that had undergone USO. The examined wrists were classified into two groups based on the sigmoid notch morphology: the linear-type notch (type L) and the curved-type notch (type C). We calculated and statistically compared the percentage of the high-density area (%HDA) in each divided region of the sigmoid notch. In type L, %HDA was significantly larger in the distal-dorsal region of the sigmoid notch before USO. Postoperatively, in type L, no specific regions showed a significantly different %HDA. In type C, %HDA was significantly larger in the distal-volar region of the sigmoid notch before USO. Postoperatively, %HDA of type C was significantly larger in the proximal-volar region. Our results suggest that in patients with ulnar impaction syndrome, morphological evaluation of the sigmoid notch can serve as a predictor of osteoarthritis in the DRUJ with or without USO.

Increased acromiohumeral distance in a double-row arthroscopic rotator cuff surgery compared to a single-row surgery after 12 months.

BACKGROUND: Arthroscopic rotator cuff surgery is an effective treatment for rotator cuff tears with the considered use of double-row repair techniques becoming popular in the last decade. We aim to compare the effects of double- and single-row arthroscopic rotator cuff repairs (ARCR) on repair integrity (RI) and acromiohumeral distance (AHD). METHODS: In this observational study, we retrospectively identified 98 patients with degenerative rotator cuff tear treated with arthroscopic rotator cuff repair between 2016 and 2019. We excluded 22 patients with partial-thickness tears, 15 with associated subscapularis or SLAP tears, 13 with massive tears, and 5 patients lost to follow-up; we included 43 patients who had ARCR for full-thickness cuff tear and clinical, radiologic follow-up. Of these 43 patients, 23 are grouped as double-row repair group (DRG) and 20 as single-row repair group (SRG). A minimum of 12 months after the surgery, bilateral shoulder MRIs were obtained. Contralateral shoulders without asymptomatic rotator cuff tears served as a control group (CG). The operating surgeon and two other surgeons experienced in arthroscopy blindly measured the AHD and determined the RI at the control MRIs in all groups. Functional assessments relied on UCLA and qDASH Scores. RESULTS: The mean age was 57.89 (45-78) years, and the mean follow-up time was 28,65 (21-43) months. The mean AHD of the CG was 9.7 ± 0.96 mm, the preoperative AHD of DRG was 8.62 ± 1.45 mm, and SRG was 9.71 ± 0.95 mm. The postoperative mean AHD of DRG 9.61 ± 1.83 mm and SRG was 10.21 ± 1.97 mm. AHD differences between the preoperative and postoperative groups were significant (P=0.009). The increase of the AHD in the double-row group was significantly higher than the single-row group (P=0.004). There was a high correlation between the RI and DASH scores (P=0.005). RI did not correlate with the repair method (P=0.580). CONCLUSION: Although double-row repairs can maintain greater AHD than single-row repairs in the clinical setting, this difference did not affect functional results. Regardless of the surgical intervention, functional results are favourable if RI is achieved. LEVEL OF EVIDENCE: Level III, Retrospective Cohort Study.

Evaluation of critical shoulder angle and acromion index in patients with anterior shoulder instability and rotator cuff tear.

OBJECTIVE: The aim of this study was to evaluate glenohumeral morphologic differences and their correlation between glenohumeral instability and rotator cuff pathology. METHODS: Two-hundred radiographs and 100 MRI scans of 100 patients in whom the diagnosis of Anterior Shoulder Instability (Anl) or Rotator Cuff Tear (RCT) was arthroscopically verified were retrospectively identified and included in the study. All the patients were categorized into two groups: 50 patients with Anl (23 female, 28 male; mean age = 29 ± 7.4) and 50 patients with RCT (28 female, 22 male). Two separate control groups were then formed, one of which included contralateral shoulders of patients in the AnI group, and the other consisted of contralateral shoulders of patients in the RCT group. The x-ray and MRI scans were examined by an orthopedic surgeon and a radiologist. The Acromial Index (AI) and the Critical Shoulder Angle (CSA) were measured on true anteroposterior shoulder radiographs; Glenoid Inclination (GI), Glenoid Version (GV), and Acromion Angulation (AA) were measured on MRI. RESULTS: In the AnI group, the measurements were as followed: AI, 0.66 ± 0.03; CSA, 33 ° ± 2.85; GI, 3.4° ± 6.2; GV, 4.1 ± 4.3; and AA, 12.9 ± 8.3. In the RCT group, AI 0.71 ± 0.04; CSA, 36° ± 2.69; GI, 9.1 ± 5; GV, 6.7 ° ± 5.7; and AA, 14.3° ± 8.7. A moderate correlation was found between CSA and GI (r = 0.41, P = 0.001) and between AI and GI (r = 0.42, P = 0.014). A weak correlation was found between AI and GI in the AnI group (r = 0.22, P = 0.001). The inter- and intra-observer intraclass correlation coefficients were respectively 0.81 and 0.84 for AI, 0.88 and 0.92 for CSA, 0.72 and 0.76 for GI, 0.69 and 0.73 for GV, and 0.72 and 0.77 for AA. CONCLUSION: The results of this study have shown that lower AI, GI, and antevert GV may be associated with AnI. Investigating CSA, AI, and GV could be useful for diagnostic evaluation of patients with AnI. LEVEL OF EVIDENCE: Level III, Diagnostic Study.

Factors associated with the development of re-tear following arthroscopic rotator cuff repair: A retrospective comparative study.

OBJECTIVE: The aim of this study was to analyze the risk factors for the development of re-tear following Arthroscopic Rotator Cuff Repair (aRCR). METHODS: This retrospective clinical study included 196 consecutive aRCRs with a minimum 3-year follow-up. Pre- and postoperative clinical and functional outcomes were measured using the Visual Analog Scale (VAS), the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), the University of California at Los Angeles Shoulder Rating Scale (UCLA), the Constant-Murley Score (CMS), and the Douleur Neuropathique (DN4) questzionnaire. The Goutallier staging of fatty infiltration, Occupational Ratio (OR), the Acromiohumeral Interval (AHI), Acromioclavicular Joint (ACJ) arthritis, acromion type, Critical Shoulder Angle (CSA), and tangent sign (tan- sign) were evaluated as radiological parameters. Different subgroup parameters were evaluated after dividing the patients into re-tear (-) and re-tear (+) groups, according to clinical and radiological outcomes as well as patient and intraoperative characteristics. RESULTS: The mean follow-up period was 72.0 ± 15.8 months. The mean age at the time of surgery was 58.4 ± 8.9 years. A significant improvement was found in clinical and functional scores in the re-tear (-) group (P < 0.001 for all). However, the retear (+) group had poorer outcome scores than the re-tear (-) group. Twenty patients (10.2%) had re-tear at the last follow-up. There was a significant difference between groups regarding pre-and postoperative clinical scores, with worse scores in the retear (+) group (P < 0.001 for all). Also, pre-and postoperative pseudoparalysis (P = 0.001 for both), acromioclavicular joint arthritis (ACJ) (P = 0.001), intraoperative rotator cuff wear (P = 0.007) or stiffness (P = 0.025), a longer time period between symptom onset and surgery (P = 0.031), larger tear size (P = 0.010), preoperative shoulder stiffness (P = 0.001), higher duration of postoperative analgesia use (P < 0.001), higher degrees of preoperative Occupational Ratio (OR) (P < 0.001), and higher degrees of fatty degeneration (P < 0.001) were found to be associated with re- tear development. CONCLUSION: Surgeons should consider the preoperative degree of fatty degeneration, clinical and functional scores, presence of ACJ arthritis, intraoperative tendon quality, tear size and chronicity as well as postoperative prolong analgesic requirement, and development of pseudoparalysis as factors regarding re-tear development risk following aRCR. LEVEL OF EVIDENCE: Level IV, Therapeutic Study.

A technique for repairing rotator cuff transtendinous tears with a remnant attached to the footprint.

BACKGROUND: Some unusual rotator cuff (RC) tears are located in more proximal tendinous portions, with substantial remnant tissue attached to the footprint. The two options for surgical repair are sacrificing or preserving the remnant tissue. We introduce a surgical repair technique that preserves as much of the remnant footprint as possible. SURGICAL TECHNIQUE: A double-loaded suture anchor is inserted into the subchondral bone at the medial portion of the RC footprint; the lateral remnant tissue is preserved. Each strand is shuttled and repassed through the medial portion of the tendon in a mattress fashion using a suture hook device. Then, multiple no. 1 PDS sutures are passed through the medial and lateral stumps and left untied. Strands from the suture anchor are first tied in a double mattress fashion. Then, the repair is completed by tying the remaining no. 1 PDS sutures. CONCLUSIONS: We propose a remnant-preserving RC repair technique for transtendinous RC tears with sufficient tissue remaining within the RC footprint. This technique appears advantageous in terms of re-establishing an environment that promotes tendon healing after repair.

Corticosteroids or platelet-rich plasma injections for rotator cuff tendinopathy: a randomized clinical trial study.

BACKGROUND: Studies evaluating the role of both corticosteroids and platelet-rich plasma (PRP) in the treatment of rotator cuff (RC) tendinopathies have been contradicting. We compared structural and clinical changes in RC muscles after corticosteroids and PRP injections. METHODS: This is a randomized double-blind clinical trial. All individuals with diagnosis of RC tendinitis during 2014-2017 were considered. Individuals were randomly allocated to either receive PRP or corticosteroids. Overall, 3cc of PRP was injected within the subacromial joint and another 3cc was injected at the site of the tendon tear, under the guide of sonography. For the corticosteroid group, 1cc of Depo-medrol 40mg and 1cc of lidocaine (2%) was injected within the subacromial joint. RESULTS: Overall, 58 patients entered the study. Comparison of pain, range of motion (ROM), Western Ontario RC (WORC), Disability of Arm-Hand-Shoulder (DASH) scores, and supraspinatus thickness showed significant improvement during follow-ups in both groups (p<0.05). During 3 months of follow-up, pain improvement was significantly better within the PRP group during (from 6.66±2.26 to 3.08±2.14 and 5.53±1.80 to 3.88±1.99, respectively; p=0.023). Regarding ROM, the PRP group had significant improvement in adduction (20.50°±8.23° to 28°±3.61° and 23.21°±7.09° to 28.46°±4.18° for the PRP and corticosteroid groups, respectively; p=0.011) and external rotation (59.66°±23.81° to 76.66°±18.30° and 57.14°±24.69° to 65.57°±26.39°, for the PRP and corticosteroid groups, respectively; p=0.036) compared to the corticosteroid group. CONCLUSION: We found that PRP renders similar results to that of corticosteroids in most clinical aspects among patients with RC tendinopathies; however, pain and ROM may show more significant improvement with the use of PRP. Considering that the use of corticosteroids may be contraindicated in some patients and may be associated with the risk of tendon rupture, we suggest the use of PRP in place of corticosteroid-based injections among patients with RC tendinopathy. TRIAL REGISTRATION: Clinical trial registration code: IRCT201302174251N9.

Which Risk Factors Are Associated with Pain and Patient-reported Function in Patients with a Rotator Cuff Tear?

BACKGROUND: Patient-reported measures guide physicians in clinical decision making and therefore it is critical to determine what clinical factors are associated with these scores. Psychological and physical factors are commonly studied separately in patients with rotator cuff tears to determine their influence on outcomes. It is well established that psychological distress and scapular motion change in the presence of a symptomatic rotator cuff tear. However, these factors have not been studied simultaneously in a clinical setting to determine their association with shoulder outcome scores. QUESTION/PURPOSE: After controlling for relevant confounding variables, what physical and psychological factors are associated with better (1) American Shoulder and Elbow Surgeons (ASES) scores for function, (2) ASES pain scores, and (3) total ASES scores? METHODS: Fifty-nine patients with a potential symptomatic rotator cuff tear were recruited and agreed to participate in this cross-sectional study. Of those, 85% (50 of 59) met eligibility criteria for a primary diagnosis of an MRI-confirmed symptomatic partial-thickness or full-thickness rotator cuff tear without a history of shoulder surgery. Demographics, rotator cuff tear size, arm flexion, and clinical scapular motion during active arm flexion were evaluated by experienced examiners using standardized procedures. Patients completed the ASES questionnaire and the Optimal Screening for Prediction of Referral and Outcomes-Yellow Flag assessment form, which measures 11 different pain-related psychological distress symptoms. Three separate stepwise multiple linear regression analyses were performed for ASES pain, function, and total scores, with significance set at p < 0.05. RESULTS: This model found that ASES function scores were associated with four factors: older age, increased arm flexion, increased percentage of scapular external rotation during arm flexion, and increased scores for acceptance of chronic pain (adjusted r2 = 0.67; p = 0.01). Those four factors appear to explain 67% of the observed variance in ASES function scores in patients with rotator cuff tears. Furthermore, increased percentage of scapular external rotation during arm flexion and decreased fear-avoidance beliefs related to physical activity scores (adjusted r2 = 0.36; p < 0.01) were associated with better ASES pain scores. And finally, better ASES total scores were associated with four factors: increased arm flexion, increased percentage of scapular upward rotation, increased scapular external rotation during arm flexion, and decreased fear-avoidance beliefs related to physical activity scores (adjusted r2 = 0.65; p < 0.001). CONCLUSION: Our results favor adopting a comprehensive biopsychological clinical assessment for patients with rotator cuff tears that specifically includes humeral and scapular motion, fear-avoidance behaviors, and pain coping behaviors along with demographics. These particular physical and psychological variables were found to be associated with the ASES and, therefore, should be clinically examined simultaneously and targeted as part of a tailored treatment plan. LEVEL OF EVIDENCE: Level II, prognostic study.

Do Relaxation Exercises Decrease Pain After Arthroscopic Rotator Cuff Repair? A Randomized Controlled Trial.

BACKGROUND: Pain after rotator cuff repair is commonly managed with opioid medications; however, these medications are associated with serious adverse effects. Relaxation exercises represent a potential nonpharmacologic method of pain management that can be easily implemented without substantial adverse effects; however, the effects of relaxation exercises have not been studied in a practical, reproducible protocol after arthroscopic rotator cuff repair. QUESTIONS/PURPOSES: (1) Does performing relaxation exercises after arthroscopic rotator cuff repair (ARCR) decrease pain compared with standard pain management medication? (2) Does performing relaxation exercises after ARCR decrease opioid consumption? (3) What proportion of patients who used the relaxation techniques believed they decreased their pain level, and what proportion continued using these techniques at 2 weeks? (4) Does performing relaxation exercises after ARCR affect shoulder function? METHODS: During the study period, 563 patients were eligible for inclusion; however, only 146 were enrolled, randomized, and postoperatively followed (relaxation group: 74, control group: 72); 68% (384 of 563) of patients were not contacted due to patient and research staff availability. Thirty-three patients were unenrolled preoperatively or immediately postoperatively due to change in operative procedure (such as, only debridement) or patient request; no postoperative data were collected from these patients. Follow-up proportions were similar between the relaxation and control groups (relaxation: 80%, control: 81%; p = 0.90). The relaxation group received and reviewed educational materials consisting of a 5-minute video and an educational pamphlet explaining relaxation breathing techniques, while the control group did not receive relaxation education materials. Patients recorded their pain levels and opioid consumption during the 5 days after ARCR. Patients also completed the American Shoulder and Elbow Surgeons shoulder score preoperatively and 2, 6, 13, 18, and 26 weeks postoperatively. Linear mixed models were created to analyze postoperative pain, opioid consumption measured in morphine milligram equivalents (MMEs), and shoulder function outcomes. A per-protocol approach was used to correct for patients who were enrolled but subsequently underwent other procedures. RESULTS: There was no difference in pain scores between the relaxation and control groups during the first 5 days postoperatively. There was no difference in pain scores at 2 weeks postoperatively between the relaxation and control groups (3.3 ± 3 versus 3.5 ± 2, mean difference -0.22 [95% CI -1.06 to 0.62]; p = 0.60). There was no difference in opioid consumption during the first 5 days postoperatively between the relaxation and control groups. The use of relaxation exercises resulted in lower 2-week narcotics consumption in the relaxation group than in the control group (309 ± 241 MMEs versus 442 ± 307 MMEs, mean difference -133 [95% CI -225 to -42]; p < 0.01). Sixty-two percent (41 of 66) of patients in the relaxation group believed the relaxation exercises decreased their pain levels. Fifty-two percent (34 of 66) were still performing the exercises at 2 weeks postoperatively. During the 6-month follow-up period, there was no difference in shoulder function between the relaxation and control groups. CONCLUSION: The preoperative administration of quick, basic relaxation exercises allowed patients to use appreciably lower opioid analgesic doses over the first 2 weeks after ARCR, without any worsening of pain scores. We consider this result promising but preliminary; it is possible that a more intense mindfulness intervention-the one we studied here was disseminated using only a 5-minute video-would deliver reductions in pain and further reductions in opioid usage. LEVEL OF EVIDENCE: Level II, therapeutic study.

The effect of the platelet-rich plasma and ozone therapy on tendon-to-bone healing in the rabbit rotator cuff repair model.

BACKGROUND: The aim of this study is to histologically and biomechanically investigate the effects of local PRP and ozone therapy (O2O3) on tendon-to-bone healing in a rabbit model of the supraspinatus tendon tear. METHODS: Four groups were formed to have seven rabbits in each group: repair, R; repair + PRP, RP; repair + ozone, RO; and repair + PRP + ozone, RPO. The supraspinatus tendon was detached by sharp dissection from the footprint and an acute tear pattern was created. Thereafter, tendon repair was performed with the transosseous technique. In the RP group, PRP, and in the RPO group, PRP + O2O3 mixture was injected to the tendon repair site. In the RO group, O2O3 gas mixture was injected into subacromial space three times a week for a total of 4 weeks. The study was ended at postoperative 6th week. RESULTS: When compared with the R group, a statistically significant increase was observed in the biomechanical strength of the RP and RPO groups. The highest increase in biomechanical strength was detected in the RPO group. The histology of the RO and RPO groups showed better collagen fiber continuity and orientation than the R and RP groups. CONCLUSIONS: The results obtained from this study show that the ozonized PRP can be used as biological support to increase tendon-to-bone healing. However, these results need to be supported by clinical studies.

Repair of high-grade partial thickness supraspinatus tears after surgical completion of the tear have a lower retear rate when compared to full-thickness tear repair.

PURPOSE: High-grade partial thickness rotator cuff tears (i.e., those involving at least 50% of the tendon thickness) are especially challenging to treat and various treatment strategies have been described. Prior studies have demonstrated equivalent outcomes between in situ tear fixation and tear completion repair techniques. However, it is unknown how repair of completed high-grade partial thickness tears to full tears compares to repair of full-thickness tears. The purpose of this study was to compare clinical outcome measures at least 1 year postoperatively between patients who had completion of a high-grade partial thickness supraspinatus tear to a full-thickness tear (PT) and those who had an isolated full-thickness supraspinatus tear (FT). The hypothesis of this study was equivalent retear rates as well as equivalent clinical and patient-reported outcomes between the two groups. METHODS: A retrospective review of 100 patients who underwent isolated arthroscopic supraspinatus repair between 2013 and 2018 with a minimum of 1 year follow-up was performed. Patients were separated into two groups based on their treatment: 56 had completion of a partial thickness supraspinatus tear to full-thickness tear with repair (PT) and 44 had isolated full-thickness supraspinatus repairs (FT). The primary outcome was rotator cuff retear, which was defined as a supraspinatus retear requiring revision repair. Secondary outcomes were patient-reported outcome measures (PROs) including visual analog pain scale (VAS) and subjective shoulder value (SSV), range of motion (ROM) and strength in forward flexion (FF), external rotation (ER), and internal rotation (IR). RESULTS: There was a significantly lower rate of retear between the PT versus FT groups (3.6% vs. 16.3%, p = 0.040). There were no significant differences between groups for all PROs, all ROM parameters, and all strength parameters (all n.s.). DISCUSSION: The data from this study demonstrated that the PT group had a significantly lower retear rate at 1 year follow-up than the FT group, while PROs, ROM, and strength were similar between the two groups. Patients with PT supraspinatus tears can have excellent outcomes, equivalent to FT tears, after completion of the tear, and subsequent repair with low retear rates. These findings may aid the treating surgeon when choosing between in situ fixation of the PT supraspinatus tear or completion of the tear and subsequent repair, as it allows the treating surgeon to choose the procedure based on comfort and experience level. LEVEL OF EVIDENCE: Level III.

Clinical short-term outcomes of articular-sided and bursal-sided partial-thickness rotator cuff tears of less than 50% in a single surgeon series: A protocol of randomized controlled trial.

BACKGROUND: There have been no published randomized clinical trial to assess the clinical outcomes between the articular-sided and bursal-sided tears. Therefore, a comparative analysis of evaluating and comparing the functional outcomes following arthroscopic repair of bursal-sided versus articular-sided partial-thickness rotator cuff tearsis essential. METHODS: This study is a present randomized controlled trial which is conducted in our hospital. Consecutive patients with symptomatic articular-sided or bursal-sided partial-thickness rotator cuff tears underwent arthroscopic repair between June 2020 and January 2022. The institutional review board approved the study proposal (with number 10012030), and informed consent was obtained from all patients. Inclusion criteria were existence of an articular- or bursal-sided tear involving <50% of the tendon thickness-confirmed intraoperatively and treated with arthroscopic debridement with or without other decompression surgery (acromioplasty/distal clavicle resection)-and a minimum follow-up of 2 years. All patients followed the same postoperative rehabilitation program. The patients were assessed at baseline preoperatively, and at 1 year and 2 years postoperatively. Outcome parameters were measured at each respective follow-up, which included active range of motion in forward flexion and abduction of the affected shoulder, pain score as measured on the Numeric Pain Rating Scale, as well as outcome scores in terms of the Constant-Murley Score, and Oxford Shoulder Score. RESULTS: Table 1 and Table 2 describe the data indicators that this article wants to evaluate and collect. CONCLUSIONS: We hypothesize that both groups of patients will show improvement in range of motion, functional outcome scores, and pain at 2 years, and that results would be similar between the two groups. TRIAL REGISTRATION: This study protocol was registered in Research Registry (researchregistry6496).

In Vivo Imaging of Fibroblast Activity Using a 68Ga-Labeled Fibroblast Activation Protein Alpha (FAP-α) Inhibitor: Study in a Mouse Rotator Cuff Repair Model.

BACKGROUND: Rotator cuff repair site failure is a well-established clinical concern. Tendon-to-bone healing is initiated by inflammatory mediators followed by matrix synthesis by fibroblasts. The kinetics of fibroblast accumulation and activity are currently poorly understood. METHODS: Ninety-six mice underwent supraspinatus tendon repair. Six were used for imaging using a novel 68Gallium (Ga)-labeled fibroblast activation protein alpha (FAP-α) inhibitor and positron emission tomography-computed tomography (PET/CT) at days 0 (before surgery), 3, 7, 14, and 28. Sixty-eight animals were divided into 4 groups to be evaluated at 3, 7, 14, or 28 days. Twenty-two native shoulders from mice without surgery were used as the control group (intact tendon). Six animals from each group were used for histological analysis; 6 from each group were used for evaluation of fibroblastic response-related gene expression; and 10 mice each from the intact, 14-day, and 28-day groups were used for biomechanical testing. RESULTS: There was minimal localization of 68Ga-labeled FAP-α inhibitor in the shoulders at day 0 (before surgery). There was significantly increased uptake in the shoulders with surgery compared with the contralateral sides without surgery at 3, 7, and 14 days. 68Ga-labeled FAP-α inhibitor uptake in the surgically treated shoulders increased gradually and peaked at 14 days followed by a decrease at 28 days. Gene expression for smooth muscle alpha (α)-2 (acta2), FAP-α, and fibronectin increased postsurgery followed by a drop at 28 days. Immunohistochemical analysis showed that FAP-α-positive cell density followed a similar temporal trend, peaking at 14 days. All trends matched closely with the PET/CT results. Biomechanical testing demonstrated a gradual increase in failure load during the healing process. CONCLUSIONS: 68Ga-labeled FAP-α inhibitor PET/CT allows facile, high-contrast in vivo 3-dimensional imaging of fibroblastic activity in a mouse rotator cuff repair model. CLINICAL RELEVANCE: Noninvasive imaging of activated fibroblasts using labeled radiotracers may be a valuable tool to follow the progression of healing at the bone-tendon interface.

Arthroscopic rotator cuff repair in patients over 70 years of age: a systematic review.

BACKGROUND: Failure of conservative treatment in patients over 70 years of age with a rotator cuff tear makes surgery a possible option, considering the increase in life expectancy and the high functional demands of elderly patients. The purpose of this systematic review of the literature was to evaluate the subjective and objective outcomes after arthroscopic rotator cuff repair in patients over 70 years of age. METHODS: A systematic review was performed to identify all the studies reporting subjective and objective outcomes in patients aged 70 years or older undergoing arthroscopic rotator cuff repair. Constant Murley Score (CMS), visual analog scale (VAS), American Shoulder and Elbow Surgeons Score (ASES), and Simple Shoulder Test (SST) were used to detect any clinical improvement after surgery. Retear and satisfaction were also analyzed. RESULTS: Out of 941 studies identified, only 6 papers have been included in the review. All studies reported improvements in postoperative functional outcome scores that exceed the minimal clinically relevant difference. The mean retear rate amounts to 21.9%, which is in line with the failure rate of rotator cuff repair in general population. Moreover, postoperative satisfaction is very high (95%). CONCLUSION: This systematic review suggests that arthroscopic rotator cuff repair in patients over 70 years of age could be a valid treatment option after failure of conservative approach. LEVEL OF EVIDENCE: 4 Trial registration The study was registered on PROSPERO (registration ID: CRD42018088613).

Biceps tenotomy versus tenodesis for lesions of the long head of the biceps tendon: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Biceps tenotomy and biceps tenodesis are 2 most common surgical procedures for long head of the biceps tendon (LHBT) pathology, but debate still exists regarding the choice of treatment. This meta-analysis was conducted to compare clinical results between tenotomy and tenodesis for the treatment of lesions of LHBT. It was hypothesized that there is no difference in outcomes of tenotomy and tenodesis for lesions of LHBT. METHODS: A comprehensive search of literature published between 1980 and April 2020 was performed using MEDLINE, EMBASE, Web of Science, and the Cochrane Library databases. Randomized controlled trials (RCTs) comparing tenotomy and tenodesis for LHBT lesions were included. The primary outcomes were Constant score and Popeye deformity. The secondary outcomes included the American Shoulder and Elbow Surgeons (ASES) score, visual analog scale (VAS) for pain, muscle strength, cramping pain, and operative time. For primary outcomes, trial sequential analysis (TSA) was conducted to reduce the risk of random errors and the GRADE (grading of recommendations, assessment, development, and evaluations) approach was used to assess the quality of the body of evidence. RESULTS: A total of 9 RCTs were included. In pooled analysis, statistical significance was observed in the Constant score (mean difference [MD], 1.59; 95% confidence interval [CI] 0.04-3.14; P = .04), Popeye deformity (risk ratio [RR], 0.33; 95% CI, 0.22-0.49; P < .00001) and operative time (MD, 9.94; 95% CI 8.39-11.50; P < .00001). However, there were no significant differences between the tenodesis and tenotomy in ASES score (P = .71), VAS for pain (P = .79), cumulative elbow flexion strength (P = .85), cumulative elbow supination strength (P = .23), and cramping pain (P = .61) TSA revealed that the results for Constant score was inconclusive. CONCLUSION: For the treatment of LHBT lesions, with the exception of constant score, there was no significant benefit of tenodesis over tenotomy. Although tenotomy is affected by a higher risk of Popeye sign, it is more timesaving.