Massive rotator cuff tears (MRCT) remain a clinical challenge, characterized by poor tendon-bone interface (TBI) healing, severe muscle degeneration, and high postoperative retear rates. Tissue engineering scaffolds offer promising alternatives, yet traditional biomaterials often lack sufficient bioactivity to orchestrate comprehensive tissue regeneration. Herein, we developed a novel graphene oxide (GO)-engineered porcine type I collagen (GO/Col) scaffold and systematically investigated its therapeutic efficacy and underlying molecular mechanisms via multi-omics analyses. Comprehensive characterization showed that GO incorporation improved scaffold stability, wettability, and biocompatibility. In vitro, the GO/Col scaffold enhanced mesenchymal stem cell adhesion and proliferation, promoted osteogenic and chondrogenic differentiation, and suppressed adipogenesis. In a macrophage model system, GO/Col was associated with a shift toward a more reparative, anti-inflammatory phenotype. Using a clinically relevant chronic MRCT rat model, we observed that GO/Col scaffolds significantly improved motor function, biomechanical properties, and tendon-bone regeneration, while inhibiting muscle fibrosis and fatty infiltration. Mechanistically, integrated transcriptomics, proteomics, and mass cytometry analyses revealed GO-mediated modulation of critical signaling pathways involved in immune regulation, stem cell differentiation, and tissue regeneration. Notably, GO activated pro-osteogenic/chondrogenic pathways and anti-inflammatory signatures, while downregulating adipogenic and pro-inflammatory pathways. Collectively, these findings support the potential of GO/Col scaffolds as a bioactive tissue-engineering strategy for chronic MRCT repair.

Introduction Fatty infiltration (FI) of the rotator cuff (RC) muscles reflects chronic deterioration in muscle quality associated with tendon injury, disuse, ageing and nerve injury. Accurate and reliable assessment of FI based on imaging interpretation is essential for evaluating muscle degeneration, guiding rehabilitation planning and enabling meaningful comparisons across clinical and research settings. Several semi-qualitative grading systems and quantitative measurement approaches across imaging modalities, including CT, MRI, ultrasound and advanced techniques such as Dixon MRI have been used to assess FI; however, the reproducibility of FI grading or quantification at the level of image interpretation varies widely. This protocol outlines a systematic review and meta-analysis designed to evaluate the inter-rater and intra-rater reliability of imaging-based FI assessment at the level of image interpretation in RC disorders.Methods and analysis The review will follow the Preferred Reporting Items for Systematic Review and Meta-Analyses Protocols (PRISMA-P) guidelines and is preregistered in PROSPERO (CRD420251242564). Searches will be conducted in MEDLINE, Embase, CINAHL, Web of Science and the Cochrane Library from inception to the search date. Two reviewers will independently screen, extract data and assess study quality using the Quality Appraisal of Reliability Studies (QAREL) checklist. The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) framework will be used to guide interpretation of reliability-related measurement properties. The primary outcomes will be inter-rater and intra-rater reliability reflecting the consistency of image-based FI grading or quantification. Where appropriate, pooled reliability estimates will be calculated separately by imaging modality (eg, MRI, CT and US) and by type of reliability (inter-rater and intra-rater). When quantitative pooling is not feasible because of limited studies or substantial heterogeneity, findings will be synthesised narratively and presented in summary tables. These will be synthesised using a restricted maximum likelihood random-effects model in R software, version 4.3.2 (R Foundation for Statistical Computing, Vienna, Austria) with the metafor package.Ethics and dissemination Ethical approval is not required as the review will use only published data. The results will be disseminated through a peer-reviewed publication and conference presentations to inform research and clinical practice in musculoskeletal imaging.PROSPERO registration number CRD420251242564.

ABSTRACT Background Massive rotator cuff tears (RCTs) often lead to superior migration and poor function. While superior capsular reconstruction (SCR) using the long head of the biceps tendon (LHBT) autograft is a promising technique, the optimal management of its distal portion (tenotomy vs. retention) remains unclear. Objective To compare the clinical outcomes of SCR by a long head of the biceps tendon (LHBT) autograft with biceps tenotomy or not in massive RCTs. Methods In this retrospective cohort study, we enrolled and followed 59 patients following SCR using the LHBT between 2016 and 2021. Patients were divided into two groups based on intraoperative management of the distal LHBT: the LHBT‐retained group and the LHBT‐tenotomy group. Statistical comparisons included repeated‐measures ANOVA, two‐way mixed‐design ANOVA, chi‐square/Fisher's exact tests, and Mann–Whitney U tests as appropriate. The visual analog scale (VAS), American Shoulder and Elbow Surgeons (ASES) score, constant score and range of motion (ROM), and the acromiohumeral distance (AHD) were assessed as outcome measures. Results No major surgical complications were observed in any patient after surgery. The VAS score (7.0 vs. 0.6), AHD (3.2 ± 1.1 vs. 7.8 ± 0.8 mm), ASES (38 vs. 92), constant score (41 vs. 80), and ROM were statistically improved compared to their preoperative values. All patients were further subdivided into two groups according to the management of the distal end of the LHBT after transposition and fixation (retained group: the distal part of the LHBT was retained; tenotomy group: the distal part of the LHBT was resected). The two groups had comparable baseline demographic and clinical characteristics. We found that tenotomy group showed more significant function improvement within 12 months postoperatively (p < 0.05) compared with retained group. Nevertheless, compared with tenotomy group, the AHD of retsained group increased by 1.9 mm (5.0 ± 1.2 mm vs. 3.1 ± 0.8mm). Postoperative imaging assessment at 2 years revealed low and comparable retear rates (grades IV–V) between groups (retained group: 9.7% vs. tenotomy group: 7.1%). Conclusion SCR using the LHBT autograft significantly improves outcomes in massive RCTs. While both techniques are effective, patients with distal biceps tenotomy (tenotomy group) exhibited superior early functional recovery (within 12 months), whereas those with an intact distal LHBT (retained group) demonstrated significantly greater improvement in AHD. Both groups achieved comparably low retear rates. Level of Evidence Level 4.

BACKGROUND:To evaluate the efficacy and safety of an all-inside, all-suture meniscal repair device for arthroscopic meniscal repair (AMR). MATERIALS AND METHODS:Patients with vertical longitudinal full-thickness meniscus tears undergoing AMR were randomly assigned to the intervention group (all-inside, all-suture meniscal repair device) or the control group (all-inside meniscal repair system). The primary efficacy endpoint was the Lysholm Knee Score (LKS) at 6 months postoperatively. Secondary efficacy endpoints included: (1) the immediate device success rate at intraoperatively; (2) LKS at 3 and 12 months postoperatively; (3) Tegner activity score (TAS) and visual analogue scale (VAS) of pain at 3, 6, and 12 months postoperatively; (5) Meniscus repair status evaluated by magnetic resonance imaging (MRI) at 6 and 12 months postoperatively. Adverse events (AEs) and device deficiencies were recorded to assess safety. Final follow-up for 12 months was completed in April 2024. RESULTS:A total of 94 patients from 5 tier-A centers in China were randomized (intervention group: n = 48; control group: n = 46). Primary outcome analysis included 91 patients (intervention group: n = 45; control group: n = 46). LKS improved significantly from baseline in both groups at 6 months (both P < 0.001), with no between-group difference in absolute scores (mean ± standard deviation: 90.85 ± 8.70 vs 90.96 ± 11.52, P = 0.503). However, covariance analysis revealed greater LKS improvements in the intervention group (mean ± standard deviation: 30.17 ± 1.65 vs 23.87 ± 1.93, P = 0.015). Safety analysis showed no significant difference in the incidence of surgery-related AEs between the groups (17.02% vs 17.39%, P = 1.000). CONCLUSION:The all-inside, all-suture meniscal repair device demonstrated comparable efficacy and safety to the controlled all-inside meniscal repair device for arthroscopic repair of vertical longitudinal full-thickness meniscus tears over 12 months. Moreover, it showed superior early improvement in knee function recovery and can be considered an alternative for AMR.

Topical nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used to treat sports injuries, but evidence-based medical guidance for their standardized and rational use is lacking. This guideline working group identified clinically important issues, obtained the full opinions of patients and clinical staff, and discussed them with the expert group. Based on evidence from the literature, the "clinical practice guidelines for topical NSAIDs in the treatment of sports injuries" were formulated following the methods and principles of international guidelines. According to these guidelines, 7 clinical concerns were ultimately selected, and 22 recommendations were formed. These included the status, indications, contraindications, efficacy, combined application, use in special populations, adverse reactions, and countermeasures of topical NSAIDs in the treatment of sports injuries. The purpose of these guidelines is to provide evidence-based recommendations for practitioners in the fields of orthopedics, sports medicine, rehabilitation medicine, and sports science, as well as other fields, in the treatment of sports injuries to promote more standardized and rational use of topical NSAIDs.

BACKGROUND:Augmented repair is an alternative strategy for the treatment of acute ligament and tendon injuries that imparts time-zero biomechanical strength to allow early loading, thereby protecting the repaired structures during the early healing process. PURPOSE:To investigate the biomechanical properties and biological healing process after suture repair of acute anterior cruciate ligament (ACL) tears with polyethylene terephthalate (PET) augmentation and compare the findings with those obtained without PET augmentation. STUDY DESIGN:Controlled laboratory study. METHODS:A total of 48 rabbits were assigned to 3 groups: a PET-augmented group, a nonaugmented suture repair group, and a natural (control) group. All 3 groups were evaluated at 4, 12, and 16 weeks after surgery. Biomechanical performance was assessed using tensile strength testing, and ACL healing and maturation were assessed using histological assessments. RESULTS:The PET-augmented group showed less anterior knee laxity at 30° of knee flexion and superior structural continuity compared with the suture group. ACL repair with PET augmentation yielded recovery of the maximum tensile load as early as 4 weeks compared with that of the natural group (110.5 ± 6.5 vs 129.0 ± 8.6 N, respectively; P = .29) and a gradual improvement in linear stiffness from 4 weeks (58.4 ± 3.9 N/mm) to 16 weeks (83.1 ± 5.1 N/mm; P = .04), approaching that of the natural group (106.7 ± 5.8 N/mm). Furthermore, histological analyses revealed that in the PET-augmented group, the ACL healed back to the proximal insertion as early as 4 weeks with angiogenesis and collagen regeneration, and the increased ligament maturity score indicated a gradual healing process from 4 to 16 weeks. CONCLUSION:Compared with nonaugmented repair, repair augmented with a PET band enhanced early ACL stability and supported healing of ACL tears in a rabbit model. CLINICAL RELEVANCE:The biomechanical and histological findings support subsequent clinical investigations using PET augmentation in patients with acute ACL tears.

Bone defects represent a prevalent and significant challenge in clinical practice. Given the inflammatory microenvironment at injury sites and the requirement for endogenous cell and tissue infiltration, there is an urgent need for an ideal biomaterial that can modulate inflammation and promote bone regeneration. We developed an innovative injectable hydrogel (CH@PUE MSN) designed for immunomodulation and bone regeneration through in situ self-assembly, incorporating puerarin and chitosan with mesoporous silica nanoparticles. In vitro experiments demonstrated that this multifunctional injectable hydrogel promotes tissue cell regeneration, reduces inflammation, inhibits osteoclast formation, induces the migration and differentiation of bone marrow mesenchymal stem cells, and facilitates bone regeneration. Furthermore, we conducted an extensive in vivo evaluation using a bone defect model, employing advanced imaging and histological analyses. Our findings indicate that this multifunctional injectable hydrogel is a promising bioactive material for bone regeneration and presents a novel strategy for the clinical management of bone defects.

Background: With the recent rise in anterior cruciate ligament (ACL) reconstruction surgeries in China, a corresponding increase in surgical failures has been observed. Variability in primary surgical techniques and the intricacies of failure mechanisms have introduced significant challenges in diagnosing failures, planning procedures, and conducting revision surgeries. Methods: In response to these challenges, the Chinese Association of Orthopaedic Surgeons (CAOS) and the Chinese Society of Sports Medicine (CSSM) initiated the development of an expert consensus on ACL reconstruction failure and revision. Utilizing a modified Delphi method, 67 domestic experts from relevant fields were invited for consensus formulation and review. Results: The expert panel achieved a high degree of consensus on twelve key aspects. The consensus clearly defines ACL reconstruction failure and outlines multiple contributing factors, with surgical errors, especially incorrect bone tunnel placement, identified as primary causes. It also emphasizes the significant impact of patient-specific variables on the likelihood of failure. Recommendations for revision surgeries include careful determination of revision indications, preserving meniscal integrity to reduce the risk of joint degeneration, and a preference for single-stage or two-stage surgeries based on individual patient evaluations. A unified approach for managing bone defects remains absent, necessitating comprehensive assessments. Graft selection should be tailored to each patient, with autografts, allografts, or synthetic ligaments as viable options. For patients with a highly positive pivot shift test or those engaged in high-demand athletic activities, anterolateral structure augmentation or reconstruction is recommended. Conclusion: The consensus emphasizes the critical need for individualized approaches in ACL revision surgery. By clearly defining failure criteria and outlining strategies for surgical revisions, these statements are expected to serve as a guide for refining clinical practice, reducing complications, and improving surgical outcomes. The translational potential of this article: 1) Establishment of Evidence-Based Clinical Guidelines: This article presents a rigorously developed expert consensus on ACL reconstruction failure and revision, providing evidence-based clinical guidelines that are directly applicable in surgical practice. The standardization of these protocols across medical institutions has the potential to reduce variability in patient care and improve surgical outcomes on a national scale. 2) Advancement of Precision Medicine in ACL Surgery: By emphasizing the need for patient-specific approaches in the management of ACL reconstruction failure, this consensus supports the advancement of precision medicine in orthopaedic surgery. The tailored recommendations for graft selection, surgical techniques, and rehabilitation protocols can lead to more personalized and effective treatments, reducing the risk of complications and enhancing recovery. 3) Catalyst for Innovation in Surgical Techniques: The article identifies critical gaps and challenges in current ACL revision practices, providing a foundation for future research and innovation. By outlining the complexities and controversies in surgical decision-making, this work serves as a catalyst for the development of new surgical techniques and technologies aimed at improving patient outcomes. 4) Framework for Future Research and Development: The consensus not only addresses immediate clinical needs but also sets a clear agenda for future research in ACL revision. By offering a structured approach to the diagnosis and management of ACL failures, this article guides both basic and translational research efforts, ensuring that future innovations are aligned with clinical realities and patient needs.

Anterior cruciate ligament (ACL) injury is one of the most common and severe sports-related knee injuries. Anterior cruciate ligament reconstruction (ACLR) is currently the primary clinical treatment. Compared with other grafts, artificial ligaments offer significant advantages in enabling early return to sports after surgery and, therefore, have been widely studied and applied in clinical practice. This review summarizes recent literature on the application of artificial ligaments in ACLR, outlining the classification of ligament materials, historical development, and advancements in biomaterial research. Although early artificial ligaments showed limited clinical efficacy, the continuous progress in materials science and tissue engineering has facilitated the use of various natural, synthetic, and composite materials in ACL artificial ligament construction, significantly improving their biocompatibility and mechanical properties. In addition, researchers have employed strategies such as surface modification, bioactive factor loading, and cell delivery to endow artificial ligaments with enhanced functionality, yielding promising results in animal studies. This review provides a comprehensive overview of the progress in artificial ligaments biomaterials, systematically summarizes the current changes and innovations in artificial ligament scaffold materials, surface modification technologies, and new auxiliary strategies and highlights auxiliary strategies used with artificial ligaments in ACLR to enhance tendon bone healing, with particular emphasis on the role of tissue engineering and biomaterials. The clinical translation prospects of these emerging strategies are also discussed.

Physical activity reduces cancer-associated mortality through multiple mechanisms, including tumor immune microenvironment (TIME) reprogramming. However, whether and how physiological interventions promote anti-tumor immunity remain elusive. Here, we report that clinically relevant voluntary exercise promotes muscle-derived extracellular vesicle (EV)-associated miR-29a-3p for tumor extracellular matrix (ECM) inhibition in patients and mouse models, thereby permitting immune cell infiltration and immunotherapy. Mechanistically, an unbiased screening identifies EV-associated miR-29a-3p in response to leisure-time physical activity or voluntary exercise. MiR-29a-3p-containing EVs accumulate in tumors and downregulate collagen composition by targeting COL1A1. Gain- and loss-of-function experiments and cytometry by time of flight (CyTOF) demonstrate that myocyte-secreted miR-29a-3p promotes anti-tumor immunity. Combining immunotherapy with voluntary exercise or miR-29a-3p further enhances anti-tumor efficacy. Clinically, miR-29a-3p correlates with reduced ECM, increased T cell infiltration, and response to immunotherapy. Our work reveals the predictive value of miR-29a-3p for immunotherapy, provides mechanistic insights into exercise-induced anti-cancer immunity, and highlights the potential of voluntary exercise in sensitizing immunotherapy.

Tendon injuries are pervasive orthopedic injuries encountered by the general population. Nonetheless, recovery after severe injuries, such as Achilles tendon injury, is limited. Consequently, there is a pressing need to devise interventions, including biomaterials, that foster tendon healing. Regrettably, tissue engineering treatments have faced obstacles in crafting appropriate tissue scaffolds and efficacious nanomedical approaches. To surmount these hurdles, an innovative injectable hydrogel (CP@SiO2), comprising puerarin and chitosan through in situ self-assembly, is pioneered while concurrently delivering mesoporous silica nanoparticles for tendon healing. In this research, CP@SiO2 hydrogel is employed for the treatment of Achilles tendon injuries, conducting extensive in vivo and in vitro experiments to evaluate its efficacy. This reults demonstrates that CP@SiO2 hydrogel enhances the proliferation and differentiation of tendon-derived stem cells, and mitigates inflammation through the modulation of macrophage polarization. Furthermore, using histological and behavioral analyses, it is found that CP@SiO2 hydrogel can improve the histological and biomechanical properties of injured tendons. This findings indicate that this multifaceted injectable CP@SiO2 hydrogel constitutes a suitable bioactive material for tendon repair and presents a promising new strategy for the clinical management of tendon injuries.

Artificial graft serves as the primary grafts used in the clinical management of sports-related injuries. Until now, optimizing its graft-host integration remains a great challenge due to the excessive inflammatory response during the inflammatory phase, coupled with an absence of tissue-inductive capacity during the regeneration phase. Here, a multi-layered regenerated silk fibroin (RSF) coating loaded with curcumin (Cur) and Zn2+ on the surface of the PET grafts (Cur@Zn2+@PET) was designed and fabricated for providing time-matched regulation specifically tailored to address issues arising at both inflammatory and regeneration phases, respectively. The release of Cur and Zn2+ from the Cur@Zn2+@PET followed a time-programmed pattern in vitro. Specifically, cellular assays revealed that Cur@Zn2+@PET initially released Cur during the inflammatory phase, thereby markedly inhibit the expression of inflammatory cytokines TNF-a and IL-1β. Meanwhile, a significant release of Zn2+ was major part during the regeneration phase, serving to induce the osteogenic differentiation of rBMSC. Furthermore, rat model of anterior cruciate ligament reconstruction (ACLR) showed that through time-programmed drug release, Cur@Zn2+@PET could suppress the formation of fibrous interface (FI) caused by inflammatory response, combined with significant new bone (NB) formation during regeneration phase. Consequently, the implementation of the Cur@Zn2+@PET characterized by its time-programmed release patterns hold considerable promise for improving graft-host integration for sports-related injuries.

Purpose:To use a finite element method to construct a patch-bridge repair model for massive rotator cuff tears (MRCTs) and investigate the effects of different suture methods and knot numbers on postoperative biomechanics. Methods:A finite element model based on intact glenohumeral joint data was used for a biomechanical study. A full-thickness defect and retraction model of the supraspinatus tendon simulated MRCTs. Patch, suture, and anchor models were constructed, and the Marlow method was used to assign the material properties. Three suturing models were established: 1-knot simple, 1-knot mattress, and 2-knot mattress. The ultimate failure load, failure mode, stress distribution of each structure, and other biomechanical results of the different models were calculated and compared. Results:The ultimate failure load of the 1-knot mattress suture (71.3 N) was 5.6 % greater than that of the 1-knot simple suture (67.5 N), while that (81.5 N) of the 2-knot mattress was 14.3 % greater than that of the 1-knot mattress. The stress distribution on the patch and supraspinatus tendon was concentrated on suture perforation. Failure of the bridging reconstruction mainly occurred at the suture perforation of the patch, and the damage forms included cutting-through and isthmus pull-out. Conclusion:A finite element model for the patch-bridging reconstruction of MRCTs was established, and patch-bridging restored the mechanical integrity of the rotator cuff. The 2-knot mattress suture was optimal for patch-bridging reconstruction of MRCTs.

Polyethylene terephthalate (PET) artificial ligaments, renowned for their superior mechanical properties, have been extensively adopted in anterior cruciate ligament (ACL) reconstruction surgeries. However, the inherent bio-inertness of PET introduces formidable barriers to graft-bone integration, a critical aspect of rehabilitation. Previous interventions, ranging from surface roughening to chemical modifications, have aimed to address this challenge; however, consistently effective techniques for inducing graft-bone integration remain scarce. Our study employed advanced surface-coating methodologies to introduce strontium-doped hydroxyapatite (SrHA) onto PET ligaments. Detailed scanning electron microscopy (SEM) examinations revealed a uniform and integrative coating of SrHA on PET fibers. Furthermore, spectroscopic analysis confirmed the steady release of strontium ions from the coated surface under physiological conditions. In-depth cellular studies proved that extracellular strontium emanating from SrHA-coated PET (PET@SrHA) ligaments actively steers the M2 macrophage polarization. Additionally, macrophages (Mφs) manifested a heightened secretion of prohealing cytokines when exposed to PET@SrHA. Subsequent investigations showed that these cytokines acted as mediators, activating integrin signaling pathways among macrophages, vascular endothelial cells, and osteoblasts. As a direct consequence, an increased rate of angiogenesis and osteogenic differentiation was observed, vital for graft-bone integration following ACL reconstruction with PET@SrHA ligaments. From a biochemical standpoint, our results pinpoint strontium ions as influential immunomodulators, sculpting the graft-bone interface's immune environment. This insight presents the SrHA-coating technique as a viable therapeutic strategy, holding sound promise for improving angiogenesis and osseointegration outcomes during ACL reconstruction using PET-based grafts.

Pulmonary fibrosis (PF) is a severe pulmonary disease with limited available therapeutic choices. Recent evidence increasingly points to abnormal lipid metabolism as a critical factor in PF pathogenesis. Our latest research identifies the dysregulation of low-density lipoprotein (LDL) is a new risk factor for PF, contributing to alveolar epithelial and endothelial cell damage, and fibroblast activation. In this study, we first integrative summarize the published literature about lipid metabolite changes found in PF, including phospholipids, glycolipids, steroids, fatty acids, triglycerides, and lipoproteins. We then reanalyze two single-cell RNA-sequencing (scRNA-seq) datasets of PF, and the corresponding lipid metabolomic genes responsible for these lipids’ biosynthesis, catabolism, transport, and modification processes are uncovered. Intriguingly, we found that macrophage is the most active cell type in lipid metabolism, with almost all lipid metabolic genes being altered in macrophages of PF. In type 2 alveolar epithelial cells, lipid metabolic differentially expressed genes (DEGs) are primarily associated with the cytidine diphosphate diacylglycerol pathway, cholesterol metabolism, and triglyceride synthesis. Endothelial cells are partly responsible for sphingomyelin, phosphatidylcholine, and phosphatidylethanolamines reprogramming as their metabolic genes are dysregulated in PF. Fibroblasts may contribute to abnormal cholesterol, phosphatidylcholine, and phosphatidylethanolamine metabolism in PF. Therefore, the reprogrammed lipid profiles in PF may be attributed to the aberrant expression of lipid metabolic genes in different cell types. Taken together, these insights underscore the potential of targeting lipid metabolism in developing innovative therapeutic strategies, potentially leading to extended overall survival in individuals affected by PF.

Tissue engineering has emerged as an advanced strategy to regenerate various tissues using different raw materials, and thus it is desired to develop more approaches to fabricate tissue engineering scaffolds to fit specific yet very useful raw materials such as biodegradable aliphatic polyester like poly (lactide-co-glycolide) (PLGA). Herein, a technique of 'wet 3D printing' was developed based on a pneumatic extrusion three-dimensional (3D) printer after we introduced a solidification bath into a 3D printing system to fabricate porous scaffolds. The room-temperature deposition modeling of polymeric solutions enabled by our wet 3D printing method is particularly meaningful for aliphatic polyester, which otherwise degrades at high temperature in classic fuse deposition modeling. As demonstration, we fabricated a bilayered porous scaffold consisted of PLGA and its mixture with hydroxyapatite for regeneration of articular cartilage and subchondral bone. Long-term in vitro and in vivo degradation tests of the scaffolds were carried out up to 36 weeks, which support the three-stage degradation process of the polyester porous scaffold and suggest faster degradation in vivo than in vitro. Animal experiments in a rabbit model of articular cartilage injury were conducted. The efficacy of the scaffolds in cartilage regeneration was verified through histological analysis, micro-computed tomography (CT) and biomechanical tests, and the influence of scaffold structures (bilayer versus single layer) on in vivo tissue regeneration was examined. This study has illustrated that the wet 3D printing is an alternative approach to biofabricate tissue engineering porous scaffolds based on biodegradable polymers.

The shoulder joint is the most prone to dislocation in the whole body, and more than 95% of them are anterior dislocation. Improper treatment after the initial dislocation is easy to lead to recurrent anterior dislocation or anterior shoulder instability, and the outcomes following conservative treatment is poor. Anterior shoulder instability can damage the soft tissue structure and bone structure that maintain the stability of shoulder joint, among which bone structure is the most important factor affecting the stability of shoulder joint. Diagnosis should be combined with medical history, physical examination, and auxiliary examination. Currently, three-dimensional CT is the most commonly used auxiliary examination means. However, various bone defect measurement and preoperative evaluation methods based on three-dimensional CT and the glenoid track theory have their own advantages and disadvantages, and there is still a lack of gold standard. Currently, the mainstream treatment methods mainly include Bankart procedure, coracoid process transposition, glenoid reconstruction with free bone graft, Bankart combined with Remplissage procedure, and subscapular tendon binding tamponade, etc. Each of these procedures has its own advantages and disadvantages. For the diagnosis and treatment of anterior shoulder instability, there are still too many unknown, further research and exploration need to be studied.

Objective To compare the clinical outcomes of arthroscopic extensor carpi radialis brevis（ECRB） insertional debridement and extracorporeal shock wave therapy（ESWT） in the treatment of lateral epicondylitis.Methods Fifty patients with chronic external humeral epicondylitis between year 2017 and 2020 were selected, and randomly divided into an arthroscopic ECRB insertional debridement surgery group（n=25） and ESWT group（n=25）,according to a random number table. Before the treatment,as well as 3,6 and 12 months after the treatment,both groups were evaluated the elbow function using the visual analog scale（VAS）, disabilities of the arm, shoulder and hand（DASH）score, and Mayo elbow performance score（MEPS）. Spearman correlation coefficient was used to analyze the correlation between the functional score and basic data of patients.Results After the treatment, the average DASH and VAS scores of both groups decreased significantly, while the average MEPS score increased significantly. Three months after the treatment, no significant difference were found between the two groups in the average DASH score（46 ± 12 vs 49 ± 11,P=0.39）,while the average MEPS score of the ESWT group was significantly higher than the surgery group（87 ± 7 vs 80± 7,P=0.002）,with the average VAS score of the ESWT group significantly lower than the latter（2± 1 vs 3 ± 1,P=0.002）. However,6 and 12 months after the treatment,there was no significant difference between the two groups in the average DASH, MEPS and VAS scores. Correlation analysis showed that the elbow joint function scores were related to gender,age and body mass index of the ESWT group,while the functional scores of the arthroscopic debridement group were related to age,the number of local seals and the degree of ECRB lesions.Conclusions Both treatments in this study are effective,and ESWT is superior to the other in terms of relieving pain in the early stage after treatment.

Background:Anterior cruciate ligament (ACL) reinjury after ACL reconstruction (ACLR) can occur on the ipsilateral or contralateral side. Limited evidence exists regarding the difference between the incidence of reinjury to either knee, which is important in developing interventions to prevent ACL reinjury. Purpose:To compare the reinjury rate of the ACL on the ipsilateral side versus the contralateral side in athletes after ACLR and investigate the risk factors that may cause different reinjury rates between the sides. Study Design:Systematic review; Level of evidence, 4. Methods:A systematic review was performed based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Studies that involved ACL reinjury in athletes after ACLR were reviewed. Considering several risk factors, including age and sex, a comparison of ACL reinjury incidence on the ipsilateral and contralateral sides was performed using a meta-analysis. Results:Of the 17 selected studies, 3 were found to be at high risk of bias, and thus, 14 (n = 3424 participants) studies were included in the meta-analysis. In this athletic population, the contralateral ACL had a significantly higher rupture rate than the ipsilateral graft (risk ratio [RR], 1.41; P < .0001). Female athletes were found to have a greater risk of ACL reinjury on the contralateral versus the ipsilateral side (RR, 1.65; P = .0005), but different results were found in male athletes. (RR, 0.81; P = .21). There was no statistical difference in the incidence rate of ACL reinjury to either side in adolescent athletes (RR, 1.15; P = .28). Conclusion:The contralateral ACL was more vulnerable to reinjury than the ipsilateral side in athletes after ACLR. Female athletes were more likely to reinjure their contralateral native ACL, while the same trend was not found in their male counterparts. The reinjury rate was comparable in both knees in adolescent athletes.

Repairing high-load connective tissues, such as ligaments, by surgically implanting artificial grafts after injury is challenging because they lack biointegration with host bones for stable interfaces. Herein, a high-performance helical composite fiber (HCF) ligament by wrapping aligned carbon nanotube (CNT) sheets around polyester fibers is proposed. Anterior cruciate ligament (ACL) reconstruction surgery shows that HCF grafts could induce effective bone regeneration, thus allowing the narrowing of bone tunnel defects. Such repair of the bone tunnel is in strong contrast to the tunnel enlargement of more than 50% for commercial artificial ligaments made from bare polyester fibers. Rats reconstructed with this HCF ligament show normal jumping, walking, and running without limping. This work allows bone regeneration in vivo through a one-step surgery without seeding cells or transforming growth factors, thereby opening an avenue for high-performance artificial tissues.