OBJECTIVE: To evaluate the effect of biodegradable magnesium alloy materials in promoting tendon-bone healing during rotator cuff tear repair and to investigate their potential underlying biological mechanisms. METHODS: Forty-eight 8-week-old Sprague Dawley rats were taken and randomly divided into groups A, B, and C. Rotator cuff tear models were created and repaired using magnesium alloy sutures in group A and Vicryl Plus 4-0 absorbable sutures in group B, while only subcutaneous incisions and sutures were performed in group C. Organ samples of groups A and B were taken for HE staining at 1 and 2 weeks after operation to evaluate the safety of magnesium alloy, and specimens from the supraspinatus tendon and proximal humerus were harvested at 2, 4, 8, and 12 weeks after operation. The specimens were observed macroscopically at 4 and 12 weeks after operation. Biomechanical tests were performed at 4, 8, and 12 weeks to test the ultimate load and stiffness of the healing sites in groups A and B. At 2, 4, and 12 weeks, the specimens were subjected to the following tests: Micro-CT to evaluate the formation of bone tunnels in groups A and B, HE staining and Masson staining to observe the regeneration of fibrocartilage at the tendon-bone interface after decalcification and sectioning, and Goldner trichrome staining to evaluate the calcification. Immunohistochemical staining was performed to detect the expressions of angiogenic factors, including vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2), as well as osteogenic factors at the tendon-bone interface. Additionally, immunofluorescence staining was used to examine the expressions of Arginase 1 and Integrin beta-2 to assess M1 and M2 macrophage polarization at the tendon-bone interface. The role of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway in tendon-bone healing was further analyzed using real-time fluorescence quantitative PCR. RESULTS: Analysis of visceral sections revealed that magnesium ions released during the degradation of magnesium alloys did not cause significant toxic effects on organs such as the heart, liver, spleen, lungs, and kidneys, indicating good biosafety. Histological analysis further demonstrated that fibrocartilage regeneration at the tendon-bone interface in group A occurred earlier, and the amount of fibrocartilage was significantly greater compared to group B, suggesting a positive effect of magnesium alloy material on tendon-bone interface repair. Additionally, Micro-CT analysis results revealed that bone tunnel formation occurred more rapidly in group A compared to group B, further supporting the beneficial effect of magnesium alloy on bone healing. Biomechanical testing showed that the ultimate load in group A was consistently higher than in group B, and the stiffness of group A was also greater than that of group B at 4 weeks, indicating stronger tissue-carrying capacity following tendon-bone interface repair and highlighting the potential of magnesium alloy in enhancing tendon-bone healing. Immunohistochemical staining results indicated that the expressions of VEGF and BMP-2 were significantly upregulated during the early stages of healing, suggesting that magnesium alloy effectively promoted angiogenesis and bone formation, thereby accelerating the tendon-bone healing process. Immunofluorescence staining further revealed that magnesium ions exerted significant anti-inflammatory effects by regulating macrophage polarization, promoting their shift toward the M2 phenotype. Real-time fluorescence quantitative PCR results demonstrated that magnesium ions could facilitate tendon-bone healing by modulating the PI3K/AKT signaling pathway. CONCLUSION Biodegradable magnesium alloy material accelerated fibrocartilage regeneration and calcification at the tendon-bone interface in rat rotator cuff tear repair by regulating the PI3K/AKT signaling pathway, thereby significantly enhancing tendon-bone healing.
Animals ; Rotator Cuff Injuries/metabolism* ; Rats, Sprague-Dawley ; Signal Transduction ; Wound Healing/drug effects* ; Alloys/pharmacology* ; Rats ; Proto-Oncogene Proteins c-akt/metabolism* ; Rotator Cuff/metabolism* ; Macrophages/metabolism* ; Magnesium/pharmacology* ; Phosphatidylinositol 3-Kinases/metabolism* ; Vascular Endothelial Growth Factor A/metabolism* ; Male ; Biocompatible Materials ; Bone Morphogenetic Protein 2/metabolism*

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.
Animals ; Rabbits ; Male ; Wound Healing ; Transplantation, Autologous ; Periosteum/transplantation* ; Rotator Cuff Injuries ; Rotator Cuff/surgery* ; Tendons/surgery* ; Biomechanical Phenomena ; Chondrocytes/transplantation* ; Tendon Injuries/surgery* ; Tensile Strength

OBJECTIVE: To investigate the effectiveness of arthroscopic double fixation and enhanced suture of long head of biceps tendon (LHBT) in situ for repairing rotator cuff tear. METHODS: A retrospective analysis was conducted on 31 patients with rotator cuff tears and LHBT injuries admitted between June 2022 and November 2023. All patients underwent arthroscopic double fixation and enhanced suture of LHBT in situ. There were 12 males and 19 females, with an average age of 61.6 years (range, 53-76 years). There were 10 cases of acute injury and 21 cases of chronic injury. According to DeOrio and Cofield classification criteria, the degree of rotator cuff tear rated as medium-sized tears in 3 cases, large tears in 12 cases, and massive tears in 16 cases. Associated injuries included 5 cases of shoulder joint adhesions, 12 cases of subscapularis muscle tears, and 31 case of shoulder impingement syndromes. The shoulder range of motion (ROM) (forward flexion, abduction, lateral external rotation, lateral internal rotation) and pain/function scores [visual analogue scale (VAS) score, University of California Los Angeles (UCLA) shoulder score, Constant-Murley score] were recorded before operation and at last follow-up. MRI at last follow-up were taken to evaluate the rotator cuff healing and structural integrity. RESULTS: All 31 surgeries were successfully completed with operation time ranging from 90 to 210 minutes (mean, 144 minutes). The 3-5 anchors (mean, 3.8 anchors) were used during operation. All incisions healed by first intention. All patients were followed up 12-29 months (mean, 18.5 months). At 3 months after operation, 2 cases developed joint adhesions, 3 had internal rotation limitations, and 2 experienced residual pain at the intertubercular groove, all resolved with conservative management. No Popeye deformity occurred during follow-up. At last follow-up, shoulder ROM (forward flexion, abduction, lateral external rotation, lateral internal rotation) and pain/function scores (VAS, UCLA, and Constant-Murley scores) showed significant improvements compared to preoperative values ( P<0.05). At last follow-up, MRI evaluation showed that the rotator cuff healing rate reached 90.3% according to the Sugaya classification criteria. LHBT exhibited normal morphology, course, and continuity without dislocation. Surrounding synovial sheath showed no thickening or effusion. CONCLUSION Arthroscopic double fixation and enhanced suture of LHBT in situ for repairing rotator cuff tear can significantly reduce shoulder joint pain, improve ROM, and achieve a high rotator cuff healing rate.
Humans ; Male ; Middle Aged ; Arthroscopy/methods* ; Rotator Cuff Injuries/physiopathology* ; Female ; Retrospective Studies ; Aged ; Range of Motion, Articular ; Suture Techniques ; Treatment Outcome ; Rotator Cuff/surgery* ; Shoulder Joint/physiopathology* ; Tendons/surgery*

OBJECTIVE: To describe a novel arthroscopic technique of modified tri-anchor double-pulley suture-bridge in repairing medium-sized supraspinatus tendon tears and evaluate the early effectiveness. METHODS: Between June 2021 and January 2024, 26 patients with medium-sized supraspinatus tendon tears who underwent arthroscopic modified tri-anchor double-pulley suture-bridge repair and met the selective criteria were included. There were 11 males and 15 females with an average age of 61.4 years (range, 43-74 years). Five patients had a significant history of trauma, while the remaining 21 patients had no apparent cause. The time from symptom onset to hospitalization was 3-25 months (mean, 7.9 months). The effectiveness was evaluated during follow-up, including the scores of University of California at Los Angeles (UCLA), American Shoulder and Elbow Surgeons (ASES), visual analogue scale (VAS), the range of forward flexion, abduction, external rotation, and internal rotation, and patient's satisfaction. Either MRI or ultrasound examination were used to evaluate structural integrity of the tendon. RESULTS: The operation time was 65-110 minutes (mean, 81.8 minutes). All patients were followed up 12-43 months (mean, 23.0 months). At 3 and 12 months after operation, the shoulder range of flexion, abduction, external rotation, and internal rotation, and the scores of VAS, UCLA, and ASES significantly improved when compared with those before operation ( P<0.05). The improvement was further observed at 12 months compared to 3 months ( P<0.05). At last follow-up, 13 patients were very satisfied with the effectiveness, 11 patients were satisfied, 1 was relatively satisfied, and 1 was dissatisfied. During follow-up, 15 patients underwent imaging examination and imaging reexamination showed that the re-tear rate of tendon was 6.6%(1/15). The remaining 11 patients refused imaging examination. Complications included partial anchor withdrawal in 1 case, shoulder stiffness in 5 cases, and mild pain in shoulder joint in 2 cases in physical activity or heavy physical activity. CONCLUSION Arthroscopic modified tri-anchor double-pulley suture-bridge technique is a novel surgical technique that uses double-loaded suture anchors as medial- and lateral-row anchors. In repairing medium-sized supraspinatus tendon tears, 6 sets of double-pulley suture-bridges can be created from one medial-row anchor; knotless medial-row can reduce re-tear rate of the tendon; good early effectiveness is obtained.
Humans ; Female ; Male ; Middle Aged ; Arthroscopy/methods* ; Adult ; Rotator Cuff Injuries/surgery* ; Aged ; Suture Techniques ; Treatment Outcome ; Suture Anchors ; Rotator Cuff/surgery* ; Range of Motion, Articular ; Tendon Injuries/surgery* ; Patient Satisfaction

OBJECTIVE: To investigate effectiveness of arthroscopic superior capsular reconstruction using a "sandwich" patch combined with platelet-rich plasma (PRP) injection in treating massive irreparable rotator cuff tears. METHODS: A clinical data of 15 patients (15 sides) with massive irreparable rotator cuff tears, who were admitted between September 2020 and March 2023 and met the selective criteria, was retrospectively analyzed. There were 8 males and 7 females with an average age of 62.1 years (range, 40-80 years). The rotator cuff tears were caused by trauma in 7 cases and other reasons in 8 cases. The disease duration ranged from 5 to 25 months, with an average of 17.7 months. According to the Hamada grading, the rotator cuff tears were rated as grade 1 in 2 cases, grade 2 in 8 cases, and grade 3 in 5 cases. All patients were underwent superior capsular reconstruction using the "sandwich" patches (autologous fascia lata+polypropylene patch+autologous fascia lata) combined with PRP injection on patches. The pre- and post-operative active range of motion (ROM) of the shoulder joint, American Shoulder and Elbow Surgeons (ASES) score, Constant-Murley score, University of California, Los Angeles Shoulder Rating Scale (UCLA) score, and visual analogue scale (VAS) score were recorded. The subacromial space was measured on the imaging and rotator cuff integrity was assessed based on Sugaya grading. RESULTS: All incisions healed by first intention after operation without any complications such as infection. All patients were followed up 12-18 months (mean, 14.4 months). At last follow-up, the active ROMs of flexion, abduction, external rotation, internal rotation of the shoulder joint, subacromial space, ASES score, Constant-Murley score, and UCLA score increased, and VAS score decreased, showing significant differences when compared with preoperative values ( P<0.05). There was no significant difference in the Sugaya grading between last follow-up and immediately after operation ( P>0.05). CONCLUSION For massive irreparable rotator cuff tears, arthroscopic superior capsular reconstruction using the "sandwich" patches combined with PRP injection can restore stability of the shoulder joint, relieve pain, promote rotator cuff healing, and achieve good short-term effectiveness.
Humans ; Platelet-Rich Plasma ; Female ; Male ; Middle Aged ; Aged ; Rotator Cuff Injuries/therapy* ; Arthroscopy/methods* ; Adult ; Retrospective Studies ; Aged, 80 and over ; Treatment Outcome ; Plastic Surgery Procedures/methods* ; Rotator Cuff/surgery* ; Range of Motion, Articular ; Shoulder Joint/surgery*

OBJECTIVE: To summarize the biomechanical research progress of biomaterials in rotator cuff injury repair and to explore how biomaterials can restore the native histological and mechanical properties of the rotator cuff. METHODS: The relevant literature at home and abroad was widely reviewed to analyze the biomechanical properties of synthetic biomaterials, naturally derived biomaterials, and tissue grafts in the repair of rotator cuff injuries. RESULTS: Synthetic biomaterials [such as poly (lactic-co-glycolic acid) and polycaprolactone] can provide initial stable mechanical support due to their adjustable mechanical properties and degradation characteristics, while naturally derived biomaterials (such as collagen and hyaluronic acid) can promote cell adhesion and tissue integration due to their biocompatibility and bioactivity. Tissue grafts exhibit significant clinical utility by providing immediate mechanical stability and promoting tendon-to-bone healing. Three-dimensional bioprinting technology provides new possibilities for personalized repair of rotator cuff injuries by precisely controlling the spatial distribution and mechanical properties of biomaterials. CONCLUSION Future studies should further optimize the design of bioprinting materials, cell sources, and scaffolds to achieve better mechanical properties and clinical efficacy of biomaterials in the repair of rotator cuff injuries.
Humans ; Rotator Cuff Injuries ; Biocompatible Materials/chemistry* ; Biomechanical Phenomena ; Tissue Scaffolds ; Rotator Cuff/surgery* ; Tissue Engineering/methods* ; Polyesters ; Polyglycolic Acid/chemistry* ; Hyaluronic Acid/chemistry* ; Collagen/chemistry* ; Lactic Acid/chemistry* ; Polylactic Acid-Polyglycolic Acid Copolymer ; Bioprinting ; Wound Healing ; Printing, Three-Dimensional ; Tendon Injuries/surgery*

OBJECTIVE: To explore early curative effect of upper joint capsule reconstruction combined with biceps tendon transposition in treating irreparable rotator cuff tears. METHODS: From October 2019 to March 2021, 16 patients with irreparable rotator cuff tear were underwent arthroscopic autogenous semitendinosus tendon transplantation for upper articular capsule reconstruction combined with biceps tendon transposition, included 12 males and 4 females, aged from 53 to 72 years old with an average of (62.13±5.35) years old; 3 patients on the left side and 13 patients on the right side. All patients had preoperatively limited joint mobility, resting pain, and mobility pain, and had a history of failure to respond to conservative treatment for more than 8 months. The duration of preoperative symptoms ranged from 45 to 144 months with an average of (85.25±32.08) months. Visual analogue scale (VAS) of shoulder pain, University of California Los Angeles (UCLA) score, Constant-Murley score, active and passive motion of shoulder joint were compared before operation and 2 years after operation, complications were recorded. RESULTS: All 16 patients were followed up for 21 to 32 months with an average of (24.25±3.57) months. There were no complications such as incision infection, vascular and nerve injury, retear occurred. VAS, UCLA and Constant-Murley scores were improved from (5.75±1.18), (11.88±3.38) and (33.38±9.34) before operation to (1.13±0.89), (32.56±2.71), (89.06±6.25) at 2 years after operation (P<0.05). Anterior flexion, abduction, lateral external rotation and lateral internal rotation of shoulder joint were improved from (79.75±21.36) °, (62.06±10.49) °, (19.19±5.41) °, (3.04±0.21) °, respectively to (156.94±13.18) °, (116.19±12.59) °, (42.63±6.07) °, (8.16±0.64) ° at 2 years after operation. Anterior flexion, abduction, lateral lateral rotation and lateral internal rotation of shoulder joint were improved from (116.28±21.47) °, (107.12±9.67) °, (27.62±4.70) °, (4.21±0.41) °, respectively to (165.28±7.15) °, (153.34±4.69) °, (52.46±4.46) °, (9.68±0.68) ° at 2 years after operation, and the difference was statistically significant (P<0.05). CONCLUSION Arthroscopic autograft of semitendinosus tendon combined with transposition of biceps tendon could achieve satisfactory early clinical results in treating patients with irreparable rotator cuff tear, which is a reliable and effective surgical method.
Humans ; Male ; Female ; Middle Aged ; Aged ; Arthroscopy/methods* ; Rotator Cuff Injuries/physiopathology* ; Plastic Surgery Procedures/methods* ; Range of Motion, Articular ; Shoulder Joint/surgery* ; Tendon Transfer

OBJECTIVE: To explore early clinical efficacy and advantages of Huoxue Fang's directional dialysis combined with extracorporeal shock wave in treating rotator cuff injury. METHODS: A retrospective analysis was performed for 42 patients with rotator cuff injury admitted from September 2020 to December 2022, and they were divided into shock wave group and directed dialysis group according to different treatment methods. There were 20 patients in shock wave group, including 12 males and 8 females; aged from 47 to 68 years old with an average of (63.2±3.3) years old;the course of disease ranged from 2 to 6 weeks with an average of (3.1±1.4) weeks;10 patients with gradeⅠand 10 patients with gradeⅡaccording to Ellman classification;non-steroidal drugs and extracorporeal shock wave therapy were performed. There were 22 patients in directed dialysis group, including 16 males and 6 females;aged from 44 to 67 years old with an average of (61.0±2.3) years old;the course of disease ranged from 2 to 8 weeks with average of (3.3±1.3) weeks;12 patients with gradeⅠand 10 patients with gradeⅡaccording to Ellman classification;with Huoxue prescription directed transdrug therapy based on shock wave group. Visual analogue scale (VAS), University of California at Los Angeles (UCLA) and range of motion (ROM) were compared between two groups before treatment, 1 and 6 months after treatment;changes of tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1) and interleukin-6 (IL-6) between two groups were detected and compared. The complications between two groups were compared. RESULTS: All patients were followed up, shockwave group followed up for 6 to 8 months with an average of (7.1±1.9) months, 6 to 8 months with an average of (7.2±1.8) months in directed dialysis group, with no statistical significance between two groups (P>0.05). At 1 and 6 months after treatment, VAS in directed dialysis group were (3.85±0.99), (1.24±0.75), which were lower than that in shock wave group (4.91±0.89), (1.81±0.84) (P<0.05). UCLA scores in directed dialysis group (25.25±2.34), (32.71±2.33) were higher than those in shock wave group (21.67±3.38) °, (29.11±3.01) °(P<0.05). Forward bending (139.15±20.39) °, (150.14±20.55) °, external rotation (63.46±16.62) °, (73.35±13.82) °, internal rotation (46.99±2.93) °, (58.24±2.10) ° in directed dialysis group were better than those in shock wave group (130.61±22.27) °, (141.28±19.47) °, external rotation (57.36±17.53) °, (68.12±13.64) °, internal rotation (41.21±3.10) °, (49.16±3.21) ° (P<0.05). At 1 and 6 months after treatment, TNF-α, IL-1 and IL-6 in directed dialysis group were (2.12±0.49), (2.06±0.55), (0.69±0.26) μg·L-1;(1.27±0.25), (1.14±0.23), (0.37±0.11) μg·L-1, which were lower than those in shock wave group (2.87±0. 51), (2.67±0.48), (0.92±0.21) μg·L-1, (1.88 ± 0.26), (1.36±0.27), (0.45±0.09) μg·L-1(P<0.05). At the latest follow-up, 8 patients got excellent result, 10 good and 2 poor in shock wave group;10 patients excellent, 10 good, and 2 poor in directed dialysis group;there was no significant difference between two groups (P>0.05). There were no complications such as skin allergy, subcutaneous hemorrhage, ecchymosis, vascular and nerve injury occurred in both groups. CONCLUSION For the treatment of rotator cuff injury, Huoxue prescription combined with extracorporeal shock wave is effective, which could not only release the local adhesion tissue, improve local blood circulation, accelerate absorption of inflammatory exudate of the local soft tissue, and promote recovery of the diseased muscle bond and ligament. It could also effectively relieve shoulder pain, improve shoulder motion, restore shoulder function, improve patients' quality of life.
Humans ; Male ; Female ; Middle Aged ; Aged ; Extracorporeal Shockwave Therapy ; Retrospective Studies ; Rotator Cuff Injuries/physiopathology* ; Adult ; Drugs, Chinese Herbal/administration & dosage* ; Combined Modality Therapy ; Interleukin-6/metabolism*

OBJECTIVE: To explore clinical effect of reverse shoulder replacement in treating giant irreparable rotator cuff tear complicated with glenohumeral arthritis. METHODS: A retrospective analysis was performed on 18 patients (18 shoulders) with glenohumeral arthritis combined with large irreparable rotator cuff tear admitted from April 2020 to April 2022, including 10 males and 8 females, aged from 60 to 78 years old;7 patients on the left side, 11 patients on the right side;the course of disease ranged from 6 to 21 months;7 patients with grade 3 and 11 patients with grade 4 according to Goutallier grading;8 patients with grade 4b and 10 patients with grade 5 according to Hamada grading. Shoulder joint motion, visual analogue scale (VAS), University of California at Los Angeles (UCLA) score and Constant-Murley shoulder joint function score and complications were compared at the latest follow-up. RESULTS: Eighteen patients were followed up for 24 to 48 months. At the latest follow-up, shoulder joint flexion ranged from 120° to 145°, abduction ranged from 100° to 130°, and rotation ranged from 45° to 60°. VAS ranged from 1 to 3;Constant-Murley score ranged from 80 to 95;and UCLA scores ranged from 27 to 35, and 6 patients obtained excellent result, 11 good and 1 average. Dislocation of shoulder joint occurred in 1 patient at 3 months after operation, but no dislocation occurred after manual reduction. The incision surface infection occurred in 1 patient at 1 week after operation, and the incision healed after anti-infection and cleaning. The other patients did not have complications such as dislocation, infection, prosthesis loosening and peripheral fracture. CONCLUSION Reverse shoulder replacement for the treatment of huge irreparable rotator cuff injury combined with glenohumeral arthritis disease, the clinical effect is good, could significantly improve shoulder joint function and improve quality of life, but still need to strengthen the prevention and treatment of postoperative complications such as dislocation and infection.
Humans ; Male ; Female ; Middle Aged ; Rotator Cuff Injuries/physiopathology* ; Aged ; Retrospective Studies ; Arthroplasty, Replacement, Shoulder/methods* ; Range of Motion, Articular ; Shoulder Joint/physiopathology*

PURPOSE: The retear rate of rotator cuff (RC) after surgery is high, and the rapid and functional enthesis regeneration remains a challenge. Whether acellular amniotic membrane (AAM) helps to promote the healing of tendon to bone and which treatment is better are both unclear. The study aims to investigate the effect of AAM on the healing of RC and the best treatment for RC repair. METHODS: Thirty-three Sprague Dawley rats underwent RC transection and repair using microsurgical techniques and were randomly divided into the suturing repair only (SRO) group (n = 11), the AAM overlaying (AOL) group (n = 11), and the AAM interposition (AIP) group (n = 11), respectively. Rats were sacrificed at 4 weeks, then examined by subsequent micro-CT, and evaluated by histologic and biomechanical tests. The statistical analyses of one-way ANOVA or Kruskal-Wallis test were performed using with SPSS 23.0. A p < 0.05 was considered a significant difference. RESULTS: AAM being intervened between tendon and bone (AIP group) or overlaid over tendon to bone junction (AOL group) in a rat model, promoted enthesis regeneration, increased new bone and cartilage generation, and improved collagen arrangement and biomechanical properties in comparison with suturing repair only (SRO group) (AOL vs. SRO, p < 0.001, p = 0.004, p = 0.003; AIP vs. SRO, p < 0.001, p < 0.001, p < 0.001). Compared with the AOL group, the AIP group had better results in micro-CT evaluation, histological score, and biomechanical testing (p = 0 0.039, p = 0.011, p = 0.003, respectively). CONCLUSION In the RC repair model, AAM enhanced regeneration of the tendon to bone junction. This regeneration was more effective when the AAM was intervened at the tendon to bone interface than overlaid above the tendon to bone junction.
Animals ; Rats, Sprague-Dawley ; Rotator Cuff Injuries/surgery* ; Amnion/transplantation* ; Rats ; Wound Healing ; Rotator Cuff/surgery* ; Male ; X-Ray Microtomography ; Tendons/surgery* ; Biomechanical Phenomena