ObjectiveTo assess the effect of microfracture and biomimetic hydrogel scaffold on tendon-to-bone healing in a rabbit rotator cuff tear model.MethodsGelatin and methacrylic anhydride were used to synthesize gelatin methacryloyl (GelMA). Then the GelMA were treated with ultraviolet rays and vacuum freeze-drying method to obtain a biomimetic hydrogel scaffold. The morphology of the scaffold was observed by gross observation and scanning electron microscope. Degradation of the scaffold was determined at different time points. Twenty-four adult New Zealand rabbits, weighting 2.8-3.5 kg and male or female, were surgically created the bilateral acute rotator cuff tear models. One shoulder was treated with microfractures on the footprint and transosseous suture (control group, n=24). The other shoulder was treated with the same way, except for putting the scaffold on the footprint before transosseous suture (experimental group, n=24). The general conditions of rabbits were observed postoperatively. Tendon-to-bone healing was evaluated by gross observation, Micro-CT, HE staining, and bio-mechanical testing at 4 and 8 weeks after operation.ResultsThe scaffold was white and has a porous structure with pore size of 31.7-89.9 μm, which degraded slowly in PBS solution. The degradation rate was about 95% at 18 days. All the rabbits survived to the completion of the experiment. Micro-CT showed that there was no obvious defect and re-tear at the tendon-to-bone interface in both groups. No difference was found in bone mineral density (BMD), tissue mineral density (TMD), and bone volume/total volume (BV/TV) between the two groups at 4 and 8 weeks postoperatively (P>0.05). HE staining showed that the fibrous scar tissue was the main component at the tendon-to-bone interface in the control group at 4 and 8 weeks postoperatively; the disorderly arranged mineralized cartilage and fibrocartilage formation were observed at the tendon-to-bone interface in the experimental group at 4 weeks, and the orderly arranged cartilage formation was observed at 8 weeks. Besides, the tendon maturation scores of the experimental group were significantly higher than those of the control group at 4 and 8 weeks (P<0.05). There was no significant difference in the ultimate load to failure and stiffness between the two groups at 4 weeks (P>0.05); the ultimate load to failure at 8 weeks was significantly higher in the experiment group than in the control group (t=4.162, P=0.009), and no significant difference was found in stiffness between the two groups at 8 weeks (t=2.286, P=0.071).ConclusionCompared with microfracture alone, microfracture combined with biomimetic hydrogel scaffold can enhance tendon-to-bone healing and improve the ultimate load to failure in rabbits.
Objectives To compare the clinical therapeutic effect of arthroscope and mini-open in treating rotator cuff impairment with Meta-analysi. Methods We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (Jun 2007), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 2, 2007), MEDLINE, EMBASE, and CBM, conference proceedings and reference lists of articles. Selection criteria: Randomized or comparative studies on all arthroscopic rotator cuff repairs and mini-open repairs. Results There were no randomized controlled trials (Level I) was found. Pooled results from all 12 trials showed that postoperative shoulder pain in all arthroscope group was statistically less than in the mini-open group (RR=0.94, 95%CI 0.28 to 1.60). Meanwhile, another evaluates outcomes such as ROM-Forward flexion (RR=0.17, 95%CI –0.10 to 0.45), patient’s satisfaction (RR=1.03, 95%CI 0.98 to 1.08), complication (RR=1.11, 95%CI 0.54 to 2.27), and shoulder functional score (RR=0.04, 95%CI –0.10 to 0.19) indicated no statistical difference in two groups. Conclusions According to Limited evidence, there are some findings as follows: comparing with mini-open treatment of rotator cuff impairment, all arthroscopic surgery can reduce the shoulder pain. Moreover, we found no statistical difference in shoulder functional score, ROM-Forward flexion, patient’s satisfaction and complication. Attention should be paid to outcome assessment in future trials.
ObjectiveTo review the research progress of indication and treatment of graft in shoulder superior capsular reconstruction (SCR) for rotator cuff tear (RCT).MethodsThe literature related to shoulder SCR in recent years was extensively reviewed, and the anatomy, biomechanics, surgical indications, and treatment of graft in SCR were summarized.ResultsSuperior capsule plays a role as a functional complex with rotator cuff, ligament, and whole capsule. SCR can effectively restore the superior stability of the shoulder. The indications of SCR include the irreparable massive RCT, massive RCT combined with pseudoparalysis shoulder, medium/large RCT with severe degenerative rotator cuff tissue, and dual-layer RCT. In order to achieve a better healing of tendon-bone in graft and decrease the rate of long-term graft retearing, it is essential to select an appropriate thickness graft, fix the graft in right intensity, and get a better capsular continuity.ConclusionThe technique of SCR advanced to SCR for reinforcement and it is indicated from substantial massive RCT to severe degeneration of rotator cuff tissue. Graft treatment is the key step for a successful SCR.
Objective To compare effectiveness of injecting platelet-rich plasma (PRP) with different concentrations of leukocytes under ultrasound in treatment of supraspinatus tendon injury. Methods A clinical data of 30 patients with supraspinatus tendon injury, who met the selection criteria and were admitted between December 2022 and December 2023, was retrospectively analyzed. Thirty patients were treated with 4 injections of leukocyte-poor PRP (LP-PRP, n=10), leukocyte-rich PRP (LR-PRP, n=11), and triamcinolone (n=9), with an interval of 7-10 days between each injection. There was no significant difference between groups (P>0.05) in the age, gender, disease duration, affected shoulder side, Ellman classification, preoperative visual analogue scale (VAS) score, Constant score, Disabilities of the Arm, Shoulder, and Hand (DASH) score, and American Shoulder and Elbow Surgeons (ASES) score. At 1, 3, and 6 months after injection, the shoulder pain and function were evaluated by using the VAS score, Constant score, DASH score, and ASES score. MRI was conducted to observe supraspinatus tendon healing. Results No severe adverse reactions was observed in all groups. All patients were followed up 6-7 months, with an average of 6.5 months. After injection, the ASES score and Constant score gradually increased in the LR-PRP group and LP-PRP group, while the VAS score and DASH score decreased, with significant differences compared to before injection (P<0.05). Except for no significant difference between 3 and 6 months after injection in LR-PRP group (P>0.05), the above scores showed significant differences between different time points (P<0.05). At 1 month after injection, the Constant score in triamcinolone group significantly increased compared to before injection, while the VAS score significantly decreased (P<0.05). There was no significant difference in all scores between other time points in the triamcinolone group (P>0.05). Except for 1 month after injection, there was no significant difference in Constant score and VAS score between groups (P>0.05). At all other time points, the LR-PRP group and LP-PRP group had better scores than the triamcinolone group (P<0.05). There was no significant difference between the LR-PRP group and the LP-PRP group (P>0.05). MRI showed that only 4 patients in the LP-PRP group had signs of repair at the supraspinatus tendon injury site at 6 months after injection, while no significant tendon repair sign was observed in the other patients. Conclusion Compared with triamcinolone treatment, multiple injections of LP-PRP and LR-PRP under ultrasound can promote the recovery of shoulder joint function and significantly relieve pain in patients with supraspinatus tendon injury, and imaging improvement can be seen after LP-PRP treatment.
Objective To study the efficacy and safety of bone channeling in arthroscopic rotator cuff repair. Methods China National Knowledge Infrastructure, Cochrane Library, Chongqing VIP, PubMed, Wanfang database and Embase were searched to collect all randomized controlled trials of the application of bone channeling in arthroscopic rotator cuff repair. The search time was from the establishment of databases to October 15, 2025. RevMan 5.3 software was used for meta-analysis to explore the differences in postoperative functional score, pain, complications, reoperation and 2-year postoperative re-tear between the bone channeling group and the control group. Results Nine randomized controlled trial studies were finally included. The results of meta-analysis showed that there were no significant differences in the postoperative Constant Function Score [mean difference (MD)=1.27], American Shoulder and Elbow Surgeons score (MD=1.26), postoperative pain score (MD=0.27), 2-year postoperative incidence of re-tear [relative risk (RR)=1.22], reoperation rate (RR=1.19) and complication rate (RR=1.37) between the bone channeling group and the control group (P>0.05). Conclusions Existing evidence shows that the application of bone channeling in arthroscopic rotator cuff repair failed to improve the postoperative re-tear of patients, but also did not lead to pain and complications.
Objective To investigate the effect of autologous osteochondral tissue and periosteum transplantation on tendon-bone healing of rotator cuff in rabbits. Methods Twenty-four male New Zealand white rabbits were randomly divided into autologous osteochondral tissue and periosteum transplantation group (experimental group, n=12) and simple suture group (control group, n=12). Both groups were subjected to acute supraspinatus tendon injury and repaired with corresponding techniques. At 4, 8, and 12 weeks after operation, 4 specimens from each group were taken from the right shoulder joint for histological examination (HE staining, Masson staining, and Safranin O-fast green staining), and the left shoulder was subjected to biomechanical tests (maximum tensile load and stiffness). Results Both groups of animals survived until the completion of the experiment after operation. At 4 weeks after operation, both groups showed less collagen fibers and disorder at the tendon-bone junction. At 8 weeks, both groups showed reduced inflammation at the tendon-bone junction, with more organized and denser collagen fibers and chondrocytes. The experimental group showed better results than the control group. At 12 weeks, the experimental group showed typical tendon-bone transition structure, with increased generation of collagen fibers and chondrocytes, and the larger cartilage staining area. Both groups showed an increase in maximum tensile load and stiffness over time (P<0.05). The stiffness at 4 weeks and the maximum tensile load at 4, 8, and 12 weeks in the experimental group were superior to control group, and the differences were significant (P<0.05). There was no significant difference in stiffness at 8, 12 weeks between the two groups (P>0.05). Conclusion Autologous osteochondral tissue and periosteum transplantation can effectively promote the fiber and cartilage regeneration at the tendon-bone junction of rotator cuff and improve the biomechanical effect of shoulder joint in rabbits.
Objective?To analyze the effect of different surgery techniques on the tendon-bone healing of rotator cuff insertion.?Methods?Forty-two adult Japanese rabbits, weighing 2.0-2.5 kg and male or female, were selected. Thirty-six rabbits were given a sharply left-lateral tenotomy of the supraspinatus tendon with subsequent re-attachment of the tendon. According to the depth of re-attachment, 36 rabbits were equally randomized into the cancellous-fixation group (a cancellous bed was prepared with a dental burr) and the cortical-fixation group (the same treatment was performed except the preparation of the bone bed). Six rabbits served as the controls without treatment (control group). At 4 and 8 weeks after operation, the general observation, HE staining, and the biomechanical test were performed.?Results?At 4 weeks after operation, the supraspinatus-humerus specimens morphologically showed atrophy and vague between tendon and new bone in the cancellous-fixation group and the cortical-fixation group; at 8 weeks, no obvious difference was observed between 2 groups and the control group. The histological results of the cortical-fixation group at 4 weeks revealed the interface between tendon and new bone became smooth. The interface became transitional at 8 weeks, and the shape of bone tissue was nearly normal. The interface obtained from the cancellous-fixation group at 4 weeks became sclerotic, and collagen fibers formed in disorder. With ingrowth of new bone and re-establishment of collagen-fiber continuity at 8 weeks, thickness of interface became thin, and bone tissue was remodeling. The ultimate load were significantly higher in the cortical-fixation group than in the cancellous-fixation group at both 4 and 8 weeks, and the results gained at 8 weeks is significantly higher than that at 4 weeks in each group (P lt; 0.05). Except rupture strength at 4 weeks between 2 groups and all tensile strength (P gt; 0.05), there were significant differences in the results of others (P lt; 0.05).?Conclusion?In this model, the tendon-bone healing process and the biomechanical properties of cortical-fixation is superior to those of cancellous-fixation.
Objective To investigate the synergistic interaction between the deltoid muscle and the rotator cuff muscle group in patients with rotator cuff tears (RCT), as well as the impact of the critical shoulder angle (CSA) on deltoid muscle strength. Methods A retrospective analysis was conducted on clinical data from 42 RCT patients who met the selection criteria and were treated between March 2022 and March 2023. There were 13 males and 29 females, with an age range of 42-77 years (mean, 60.5 years). Preoperative visual analogue scale (VAS) score was 6.0±1.6. CSA measurements were obtained from standard anteroposterior X-ray films before operation, and patients were divided into two groups based on CSA measurements: CSA>35° group (group A) and CSA≤35° group (group B). Handheld dynamometry was used to measure the muscle strength of various muscle group in the shoulder (including the supraspinatus, infraspinatus, subscapularis, and anterior, middle, and posterior bundles of the deltoid). The muscle strength of the unaffected side was compared to the affected side, and muscle imbalance indices were calculated. Muscle imbalance indices between male and female patients, dominant and non-dominant sides, and groups A and B were compared. Pearson correlation analysis was used to examine the relationship between muscle imbalance indices and CSA as well as VAS scores. Results Muscle strength in all muscle groups on the affected side was significantly lower than on the unaffected side (P<0.05). The muscle imbalance indices for the supraspinatus, subscapularis, infraspinatus, and anterior, middle, and posterior bundles of the deltoid were 14.8%±24.4%, 5.9%±9.7%, 7.2% (0, 9.1%), 17.2% (5.9%, 26.9%), 8.3%±21.3%, and 10.2% (2.8%, 15.4%), respectively. The muscle imbalance indices of the anterior bundle of the deltoid, supraspinatus, and infraspinatus were significantly lower in male patients compared to female patients (P<0.05); however, there was no significant difference in muscle imbalance indices among other muscle groups between male and female patients or between the dominant and non-dominant sides (P>0.05). There was a positive correlation between the muscle imbalance indices of infraspinatus and VAS score (P<0.05), and a positive correlation between CSA and the muscle imbalance indices of middle bundle of deltoid (P<0.05). There was no correlation between the muscle imbalance indices of other muscle groups and VAS score or CSA (P>0.05). Preoperative CSA ranged from 17.6° to 39.4°, with a mean of 31.1°. There were 9 cases in group A and 33 cases in group B. The muscle imbalance indices of the anterior bundle of the deltoid was significantly lower in group A compared to group B (P<0.05), while there was no significant difference in muscle imbalance indices among other muscle groups between group A and group B (P>0.05). ConclusionPatients with RCT have a phenomenon of deltoid muscle strength reduction, which is more pronounced in the population with a larger CSA.
Objective To explore the causal relationship between breast cancer and rotator cuff injury using bidirectional two-sample Mendelian randomization. Methods Instrumental variables for breast cancer and rotator cuff injury were extracted from published genome-wide association study data. The positive study used breast cancer as the exposure and rotator cuff injury as the outcome, with single nucleotide polymorphisms (SNPs) closely associated with both breast cancer and rotator cuff injury as genetic instrumental variables. The reverse study used rotator cuff injury as the exposure and breast cancer as the outcome, with SNPs closely associated with both breast cancer and rotator cuff injury as genetic instrumental variables. Bidirectional MR analysis was conducted using five models: inverse variance weighted (IVW), simple model, weighted median, weighted model, and MR-Egger to assess the causal relationship between breast cancer and rotator cuff injury. Cochran Q test was used to detect heterogeneity, MR-Egger to detect horizontal pleiotropy, and leave-one-out method for sensitivity analysis to ensure the robustness of the results. Results A total of 51 SNPs closely associated with breast cancer were included in the forward study. The results indicated a positive causal association between breast cancer and an increased risk of rotator cuff injury [IVW: odds ratio=1.08, 95% confidence interval (1.02, 1.12), P=0.014], with no evidence of heterogeneity in the causal relationship between breast cancer and rotator cuff injury (P>0.05). Horizontal pleiotropy test results showed no horizontal pleiotropy in the SNPs (P>0.05). Leave-one-out test results did not detect any SNP with a large impact on the results. In the reverse study, a total of 3 SNPs related to rotator cuff injury were included as instrumental variables. There was no strong evidence that rotator cuff injury had a causal effect on breast cancer incidence [IVW: odds ratio=0.95, 95% confidence interval (0.86, 1.05), P=0.334]. Conclusions There is a potential causal association between breast cancer and rotator cuff injury. Therefore, it is suggested to increase the screening for rotator cuff injury in breast cancer patients.
ObjectiveTo compare the difference of rotator cuff healing between different types of injury and between different repair methods, and to explore the animal model to accurately simulate the restorative process after repair of rotator cuff injury. MethodTwelve adult male beagle dogs (weighing, 10-15 kg) were divided into 3 groups (n=4) according to different processing methods:acute rotator cuff injury+Mason-Allen suture repair (group A), huge rotator cuff injury+Mason-Allen suture repair (group B), and huge rotator cuff injury+Mason-Allen combined with autogenous semitendinosus expansion suture repair (group C). The external fixation was used for immobilization after repair. After operation, the general situation of the animals was observed, and the infraspinatus tendon was harvested for gross observation at 6 weeks after operation. The biomechanical test of limit load and histological observation of tendon fibers were carried out. ResultsAll the animals survived to the end of the experiment. All incisions healed well and no infection occurred. Gross observation showed more scar tissues at the end of infraspinatus muscle tendon than normal tendon in group A; no obvious tendon tissue was observed at the end of infraspinatus muscle tendon in group B; the infraspinatus muscle tendon was covered with some white scar tissue, but the tendon and the general direction could be observed in group C. The limit load of groups A, B, and C were (223.75±24.28) , (159.25±34.87) , and (233.25±14.24) N respectively, group B was significantly lower than groups A and C (P<0.05) , and no significant differnce was found between group A and group C (P>0.05) . Histological observation showed normal arrangement of tendon fibers in group A; tendon fibers arranged disorderly in group B and tendon cells were significantly less than those of group A; tendon fibers arranged in neat in group C and tendon cells were more than those of group B. ConclusionsCanine autologous semitendinosus expansion repair of massive rotator cuff injury immobilization model can better simulate the clinical rotator cuff injury healing process, so it can be used as an ideal animal model for related research.