BACKGROUND:Achilles tendon rupture is a frequent and significant injury encountered in sports medicine and clinical practice. Among the various tendon repair techniques, the Krackow suture method is the most widely used due to its proven reliability. However, the Krackow suture has several limitations, such as insufficient mechanical strength, inadequate preservation of the surrounding blood supply, and suboptimal support for tendon healing. To address these challenges, the authors have developed a novel surgical method called the H-loop knotless double-row repair (HLDR) technique, which aims to enhance tendon fixation, improve vascular protection, and provide better support for tendon healing during the recovery phase. PURPOSE:To compare the biomechanical and histological outcomes of HLDR and Krackow for Achilles tendon rupture in a rabbit model. STUDY DESIGN:Controlled laboratory study. METHODS:Acute transverse rupture models were created on the Achilles tendons of 36 New Zealand White rabbits. The animals were sacrificed at 4-, 8- and 12-weeks post-surgery, with 18 rabbits allocated for histological evaluation and the remaining 18 for biomechanical and MRI testing. RESULTS:Biomechanical analysis demonstrated that the HLDR group exhibited greater ultimate load to failure and stiffness at 8 and 12 weeks compared to the Krackow group. Furthermore, radiological and histological evaluations indicated that the HLDR technique was more effective than the Krackow technique in promoting neovascularization and facilitating tendon healing. CONCLUSION:In a rabbit model, the H-loop knotless double-row technique showed notable improvements in biomechanical strength at 8-12 weeks and earlier histological maturation relative to Krackow, while some endpoints converged by 12 weeks. These preclinical findings support HLDR as a promising approach warranting further clinical evaluation. CLINICAL RELEVANCE:This animal study suggested that HLDR might be an alternative for Achilles tendon rupture in humans to increase histological healing and reduce re-rupture.

Peritendinous adhesion represents a prevalent and debilitating complication following tendon injury and surgical repair, resulting in significantly impaired joint mobility and functional disability. Transforming growth factor-beta (TGF-β) has been identified as a pivotal mediator in adhesion-related pathophysiology, orchestrating excessive collagen synthesis and pathological adhesion formation. Previous investigations have demonstrated that arginine-glycine-aspartic acid (RGD) peptides can specifically bind to integrin αvβ3 receptors, thereby attenuating fibrotic processes through competitive inhibition of TGF-β cellular uptake. However, the therapeutic application of RGD peptides presents a clinical dilemma, as the fibrotic response essential for proper tendon healing is also TGF-β-dependent. To address this challenge and achieve optimal therapeutic balance, we developed biocompatible poly(ethylene glycol)-poly(lactic-co-glycolic acid) (PEG-PLGA) nanoparticles engineered for sustained and controlled RGD release. Through localized peritendinous injection, RGD-PEG-PLGA nanoparticles successfully achieved dual therapeutic objectives: substantial reduction of pathological adhesion formation while preserving essential tendon healing capacity. In a well-established rat Achilles tendon rupture model, treatment with RGD-PEG-PLGA nanoparticles resulted in significant attenuation of peritendinous adhesion and marked suppression of TGF-β and Smad3 expression in peritendinous fibroblasts, without compromising the mechanical properties necessary for functional tendon repair. These findings conclusively demonstrate that sustained, targeted delivery of RGD peptides via PEG-PLGA nanoparticles effectively minimizes pathological adhesion formation while maintaining optimal conditions for tendon regeneration. This innovative nanomedicine approach represents a promising clinical strategy with significant translational potential for managing post-operative adhesion complications and preventing joint stiffness, ultimately improving long-term functional outcomes for patients with tendon injuries.

BACKGROUND:Arthroscopic cortical surface tenodesis has been established as an effective technique for managing lesions of the long head of the biceps tendon (LHBT). However, traditional suture techniques frequently provide insufficient initial mechanical strength, which may contribute to tenodesis failure. To address this limitation, the Lark-Loop suture technique was developed. PURPOSE:To compare the biomechanical, histological, and radiological outcomes of Lasso-Loop, Lark-Loop, and Krackow suture techniques for cortical surface tenodesis of the LHBT in a rabbit model. STUDY DESIGN:Controlled laboratory study. METHODS:A total of 75 New Zealand White rabbits underwent bilateral proximal biceps tenodesis using a cortical surface fixation model. Animals were randomly assigned to 1 of 3 groups: (1) Lasso-Loop suture (control group; n = 25), (2) Lark-Loop suture (experimental group; n = 25), and (3) Krackow suture (positive control group; n = 25). At 4, 8, and 12 weeks postoperatively, 21 rabbits from each group (n = 63 total) were sacrificed for evaluation: 3 rabbits per group were used for magnetic resonance imaging and histological analysis, and 4 rabbits per group for micro-computed tomography and biomechanical testing. An additional 12 rabbits (4 per group) were used for initial biomechanical testing at week 0. One-way analysis of variance and Bonferroni post hoc correction were used to assess between-group differences. A P value <.05 was considered statistically significant. RESULTS:Macroscopically, complete healing at the tenodesis site was observed in all groups at 12 weeks. The Lark-Loop group demonstrated significantly improved signal-to-noise quotient values, mechanical strength, new bone formation, and histological tendon-bone integration compared with the Lasso-Loop group at all time points. No significant differences were observed between the Lark-Loop and Krackow groups. CONCLUSION:This study demonstrated that all 3 suture techniques achieved effective tendon-bone healing in a rabbit model. The Lark-Loop technique provided enhanced biomechanical properties and histological healing compared with the Lasso-Loop technique, and comparable outcomes to the Krackow stitch. CLINICAL RELEVANCE:The findings suggest that the Lark-Loop technique may serve as a viable arthroscopic alternative for LHBT tenodesis in clinical practice, potentially enhancing tendon-bone healing and reducing failure rates.

BACKGROUND:Although arthroscopic single-row repair is a common approach for treating subscapularis tendon tears, its tendon-to-bone healing efficacy remains to be fully validated, particularly in terms of collagen remodeling and local inflammatory response. The H-loop knotless technique aimed to simplify the procedure and enhance repair stability. However, its healing outcomes compared with either the single-row (SR) or modified Mason-Allen (MMA) technique require experimental evaluation. PURPOSE:The aim of the study was to compare single-row, MMA, and H-loop techniques for repairing upper one-third subscapularis tendon tears in a rabbit model. The study focused on the inflammatory response at the tendon-bone interface, collagen remodeling, biomechanical properties at different time points, and the magnetic resonance imaging (MRI) signal-to-noise ratio (SNR) of the tendon-bone interface. STUDY DESIGN:Controlled laboratory study. METHODS:A total of 63 New Zealand White rabbits underwent bilateral upper one-third subscapularis tendon injury. The animals were assigned randomly into 3 groups: single-row group, MMA group, and H-loop group. At postoperative week 0, a total of 3 animals from each group were euthanized for biomechanical testing. At weeks 4, 8, and 12, another 6 animals from each group were euthanized: 3 for histological analysis and 3 for MRI and biomechanical assessments. RESULTS:At 12 weeks postoperatively, all groups showed evidence of tendon-to-bone healing, characterized by histological maturation with organized collagen fibers and fibrocartilage formation, improved biomechanical strength, and decreased SNR on MRI. At 12 weeks, the H-loop and MMA groups demonstrated significantly superior tendon-to-bone healing compared with the single-row group, with higher tissue maturity scores (H-loop 15.66 ± 0.51 and MMA 14.33 ± 1.03 vs single-row 12.00 ± 0.89; P < .0001), larger fibrocartilage formation areas (H-loop 0.17 ± 0.02 mm2 and MMA 0.17 ± 0.003 mm2 vs single-row 0.13 ± 0.003 mm2; P < .0001), and greater maximum failure loads (H-loop 102.58 ± 1.69 N and MMA 103.31 ± 2.22 N vs single-row 97.44 ± 2.28 N; P < .01). The H-loop and MMA groups also exhibited improved inflammatory regulation, with significantly lower M1/M2 macrophage ratios and reduced expression of cluster of differentiation 86 (CD86) and interleukin 6 (IL-6), while maintaining higher expression of the anti-inflammatory markers cluster of differentiation 206 (CD206) and transforming growth factor β (TGF-β). Notably, the H-loop group had a more mature collagen remodeling pattern, with significantly higher type I collagen deposition at the tendon-bone interface compared with the other 2 groups. MRI assessments revealed a lower SNR in the H-loop group, suggesting better tissue integration. CONCLUSION:All 3 techniques achieved satisfactory healing. Of these techniques, the H-loop and MMA techniques were superior to the single-row technique for modulating the inflammatory response and providing biomechanical strength. In addition, the H-loop technique resulted in more mature histological structures and a lower SNR. CLINICAL RELEVANCE:Although this study was conducted in a rabbit model, the findings suggest that the H-loop knotless repair technique may offer biomechanical and biological advantages for subscapularis tendon repair. These results provide a foundation for future translational research and may inform surgical decision-making upon further validation in clinical settings.

Bone-related diseases resulting from accidents, illnesses, and injuries have become increasingly common in recent years. Treating these conditions poses significant challenges, including prolonged recovery times, high costs, and unpredictable outcomes, which can lead to complications such as infections and reduced muscle strength. Although autologous bone transplantation is regarded as the "gold standard" for addressing bone diseases, its application is often limited by complications at the donor site and the risk of infection. This underscores the urgent need to explore alternatives to autogenous bone transplantation. In response, a range of biomaterials for bone repair have been developed, with metal-based biomaterials emerging as effective adjuncts that enhance and optimize the repair and regeneration of bone tissue. These materials can actively influence the bone repair process through mechanisms such as inductive osteogenesis, immunomodulation, and pro-angiogenesis. This review begins by highlighting the biological effects of metal-based biomaterials, followed by a comprehensive overview of their macro- and microscale classifications and applications for treating various bone diseases. Finally, the review addresses future directions and challenges associated with the use of metal-based biomaterials in bone repair, aiming to propose promising strategies for the treatment of bone-related diseases. (c) 2026 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.

It is observed in clinical practice that worse healing in rotator cuff tear (RCT) is closely associated with osteoporosis in patients. Herein, from the statistical analysis, we further confirmed that the RCT is significantly increased in postmenopausal women who suffer from decreased bone mineral density (BMD), suggesting intervention of osteoporosis as a potential strategy in the management of RCT in aged women. Our previous studies showed that Growth arrest-specific 5 (GAS5), a long non-coding RNA (lncRNA), could promote bone formation, and alleviate osteoporosis. Herein, we demonstrated an enhancement of RCT healing by intraarticular administration of the GAS5 delivered with lipid nanoparticles (LNPs). Firstly, different kinds of ionizable lipids were applied to screen the capability of LNPs to deliver GAS5 in vitro to bone marrow mesenchymal stem cells (BMSCs) and the best-performing lipid was applied for in vivo evaluation in treating RCT rat models with osteoporosis by intraarticular injection. We found that GAS5-LNPs could improve bone quality and macrophage transformation into M2 type of the models with osteoporosis and facilitate healing of RCT. The therapeutic outcome with RCT rats demonstrated that tendon morphology, mechanical properties and bone quality of the rotator cuff were greatly improved. Thus, this study provides a new strategy to treat RCT by improving bone quality with formulated GAS5 by LNP, which is promising for clinical application.

ABSTRACT Objective Arthroscopic repair of upper one‐third subscapularis tendon tears remains challenging due to suture management difficulties and repair quality limitations. We proposed a simpler knotless technique—the H‐Loop technique. This study evaluates its early clinical and imaging outcomes. Method This is a case series of 38 patients (9 males and 29 females), who underwent arthroscopic H‐Loop technique repair for upper one‐third subscapularis tendon tears between January 2021 and August 2023. Postoperative assessments include the American Shoulder and Elbow Surgeons (ASES) score, the University of California, Los Angeles (UCLA) shoulder score, the Constant‐Murley score, the visual analog scale (VAS), range of motion (ROM) (internal and external rotation), and internal rotation strength. In addition, MRI (30 patients) evaluated fatty infiltration, re‐tears, and subscapularis integrity, comparing tendon dimensions and signal‐to‐signal ratios with a control group of patients with normal subscapularis tendons. Result Preoperative symptom duration ranged from 3 to 36 months, with an average of 9 months. Follow‐up ranged from 12 to 14 months, with an average duration of 12.6 months. No complications were observed in any patient. Postoperative ASES scores increased significantly compared to preoperative scores (55.63 ± 15.85 vs. 88.92 ± 8.24), as did UCLA scores (21.82 ± 4.44 vs. 29.74 ± 3.55) and Constant‐Murley scores (69.76 ± 15.30 vs. 86.34 ± 14.48). VAS scores decreased significantly (5.16 ± 1.84 vs. 0.89 ± 0.76). Postoperative ROM showed significant improvement in internal rotation (7.79 ± 2.07 vs. 8.45 ± 1.33) and external rotation (57.63° ± 15.84° vs. 66.58° ± 9.08°) (p < 0.05). Internal rotation strength ratios increased markedly (78.00% ± 15.86% vs. 91.97% ± 6.62%). MRI indicated no re‐tears or fatty infiltration in the 30 patients, and compared to the control group, there were no statistically significant differences in the vertical diameter of the subscapularis muscle (62.89 mm ± 9.30 mm vs. 59.41 mm ± 7.55 mm; p = 0.153), transverse diameter of the upper subscapularis muscle (17.82 mm ± 3.79 mm vs. 19.43 mm ± 4.76 mm; p = 0.395), transverse diameter of the lower subscapularis muscle (24.09 mm ± 5.84 mm vs. 25.23 mm ± 5.41 mm; p = 0.870), cross‐sectional area of the subscapularis muscle (1338.54 mm2 ± 277.26 mm2 vs. 1247.94 mm2 ± 210.55 mm2; p = 0.098), signal‐to‐signal ratio of the upper subscapularis muscle (1.18 ± 0.28 vs. 1.24 ± 0.28; p = 0.792), or the signal‐to‐signal ratio of the lower subscapularis muscle (1.02 ± 0.24 vs. 1.03 ± 0.16; p = 0.128). Conclusion The arthroscopic H‐Loop technique significantly restores function, improves range of motion, and enhances internal rotation strength, maintaining good tendon integrity in the early postoperative period.

Mycobacterium wolinskyi (M. wolinskyi), which is a rare rapidly growing mycobacterium (RGM), and the infections it causes are predominantly linked to surgery or invasive procedures. We detailed a case of refractory surgical site infection (SSI) caused by M. wolinskyi. The causative pathogen was identified by metagenomic next-generation sequencing (mNGS) analysis, 16S rRNA and rpoB gene sequencing. What renders this case particularly remarkable is the complexity introduced by a series of antibiotic-induced adverse effects, which seem to be deeply intertwined with the patient's underlying metabolic syndrome. With the meticulous pharmaceutical guidance provided by the clinical pharmacist, the patient experienced a substantial improvement in his knee joint infection.

The global incidence of frozen shoulder (FS) (2

Carpal tunnel syndrome (CTS) is the most prevalent peripheral nerve entrapment disorder, often requiring surgical intervention. While Ultrasound-guided Looped Thread Carpal Tunnel Release (LTCTR) offers a minimally invasive alternative to carpal tunnel release, its implementation faces limitations due to insufficient specialized instruments. This cadaveric study assesses the Hybrid-J Shape Needle (HJSN), a blunt-tip, J-shaped device designed to improve safety in LTCTR procedures. Twenty fresh-frozen cadaveric specimens (40 wrists) were included. Ten junior surgeons were randomly assigned two cadavers, performing LTCTR with normal cannula needle (NCN) on one wrist of the same cadaver, followed by HJSN on the contralateral wrist. Intraoperative structural damage such as nerve, blood vessel and tendon were assessed by blinded observer and anatomist. Post-procedural dissection confirmed transverse carpal ligament (TCL) transection completeness. Surgeons evaluated usability, adoption intent, and likelihood of recommendation using 5-point Likert scales. Biomechanical testing assessed force thresholds required for tendon and nerve penetration. Statistical analysis included Mann-Whitney U-test, Student’s t-test, and Chi-square tests. HJSN reduced operative time compared to NCN (25.10 ± 6.50 vs. 31.49 ± 6.36 min, p < 0.01) and achieved 100

We evaluated the biomechanical performance of the new knotless H-Loop technique in repairing the upper third subscapularis (SSC) tendon tear, and compared these results with the single-row knotted technique. A total of 69 subscapularis tendons from sheep were collected, with 10 specimens randomly selected for comprehensive biomechanical testing after either complete tendon or upper third tear. An additional five specimens were dedicated to measuring the size and extent of the footprint area of the SSC tendon. The remaining 44 specimens were randomly and evenly divided into two groups: H-Loop(n = 11) and single-row knotted groups(n = 11). Contact area and pressure, ultimate tensile strength, stiffness, and elongation were assessed. Compared to the single-row knotted technique, the footprint contact pressure repaired by H-Loop technique was significantly larger (mean difference = 5.09 N, p = 0.004), but the footprint contact area (64.09 ± 10.37mm2) was similar to that of single-row knotted technique (58.27 ± 9.84mm2). The ultimate tensile strength and stiffness of the H-Loop technique were significantly greater than those of the single-row knotted technique (mean difference = 16.58 N, p = 0.003; mean difference = 0.82 N/mm, p = 0.002), while the peak-to-peak elongation was significantly lower (mean difference = 0.51 mm, p = 0.030). The primary failure mode for single-row knotted techniques is suture cut-through at the suture–tendon interface, while for the H-Loop technique, the main failure mode is related to the eyelet. The H-Loop technique provides higher tendon-bone contact pressure and mechanical strength with a smaller gap between the tendon and bone compared to the single-row knotted technique.

Osteoarthritis (OA) is a chronic degenerative disease characterized by joint degradation and severe pain, with no effective clinical treatments currently available. Biomaterials, due to their functional and structural diversity, hold significant clinical translation potential to meet various needs in OA management. However, the development of biomaterial scaffold strategies must align closely with advancements in the understanding of OA pathophysiology. This review revisits the interplay between aging, hypoxic microenvironments, and OA progression from a novel perspective. It details the aging-related phenotypes characterized by impaired autophagy and inflammation in various OA-affected tissues and introduces NDRG-mediated hypoxia regulation mechanisms that function independently of the hypoxia-inducible factor (HIF) family. Additionally, it systematically summarizes biomaterial scaffold strategies for OA treatment, including hydrogels, nanoparticles, microneedles, and exosomes. These strategies, inspired by new insights, aim to enhance drug bioavailability, reduce systemic effects, prolong therapeutic duration, and ameliorate the adverse microenvironment of OA through multiple modes of action. This approach holds promise for providing novel ideas for microenvironment-targeted interventions in other degenerative diseases.

Frozen shoulder (FS) manifests as progressively worsening pain and a reduction in shoulder range of motion (ROM). Salvianolic acid B (SaB) is recently expected to be used in the treatment of fibrosis diseases including FS. We firstly demonstrate that SaB can effectively hinder the progression of oxidative stress, inflammation, and pathological fibrosis within the synovial tissue in FS, potentially leading to the reduction or reversal of capsule fibrosis and joint stiffness. For further clinical application, we design and synthesize a novel, superior, antioxidant and antibacterial CSMA-PBA/OD-DA (CPDA) hydrogel for the delivery of SaB. In vitro experiments demonstrate that the CPDA hydrogel exhibits excellent biocompatibility and rheological properties, rendering it suitable for intra-articular injections. Upon injection into the contracted joint cavity of FS model rat, the SaB-CPDA hydrogel accelerate the recovery of ROM and exhibit superior anti-fibrosis effect, presenting the promise for the treatment of FS in vivo.

ObjectiveThe sub‐acromioclavicular (SAC) decompression is often performed during arthroscopic rotator cuff repair. However, the impact of SAC decompression on patients with postoperative shoulder stiffness (POSS) are controversial and unclear. This study is aim to evaluate the impact of additional sub‐acromioclavicular (SAC) decompression during arthroscopic rotator cuff repair on the postoperative shoulder stiffness (POSS) in patients.MethodsThis retrospective study examined digital data from patients with full‐thickness rotator cuff tears who underwent arthroscopic rotator cuff repair at a local institution. Patient‐reported outcomes were evaluated using the American Shoulder and Elbow Surgeons (ASES) Score, the University of California–Los Angeles (UCLA) score, and visual analog scale (VAS) scores. Restricted shoulder mobility occurring within 6 months postoperatively, lasting more than 12 weeks, characterized by a passive forward flexion angle of <120° or an external rotation angle of <30°, with or without associated shoulder pain was identified as POSS. Factors affecting POSS were analyzed by binary logistic regression analysis. The patient‐reported outcomes scores were analyzed by generalized estimating equations to examine the impact of SAC decompression.ResultsA total of 155 patients met the set criteria and were included in the study. The analysis of binary logistic regression showed that diabetes (p = 0.001) and SAC decompression (p = 0.003) were independent factors for POSS. In the analysis of each follow‐up point, only at the 3‐month follow‐up, the ASES scores (p = 0.003), UCLA scores (p = 0.045), and VAS scores (p = 0.005) showed significant differences between the SAC decompression group and the non‐decompression group. For the intergroup comparison, the results showed a significant difference in the ASES scores (β = −4.971, p = 0.008), UCLA scores (β = −1.524, p = 0.019), and VAS scores (β = 0.654, p = 0.010) throughout the study duration between the SAC decompression group and the non‐decompression group.ConclusionThe findings of this study suggested that SAC decompression during arthroscopic rotator cuff repair increase the risk of POSS compared with those without the decompression, which indicate surgeons do not perform SAC decompression unless necessary.

The subscapularis tendon is more challenging and riskier to repair than the posterior upper rotator cuff. The knotless anchor suture in subscapularis repair simplified the repair process and had an excellent postoperative effect. We describe a new knotless anchor stitching method, the H-Loop technique. The simplicity and efficiency of the technique make it particularly suitable for small subscapular tendon tears.

Previous research has established connections between the acromion index (AI), critical shoulder angle (CSA), acromiohumeral distance (AHD), and lateral acromion angle (LAA) with the incidence of rotator cuff tears (RCTs). Despite numerous international studies exploring the variability of shoulder joint morphology and parameters, research incorporating these parameters has yet to be conducted in Somalia. This study aims to analyze and describe the radiological parameters of acromion morphology in the Somali populations. Furthermore, to investigate the relationship of these parameters with rotator cuff tears within the Somali population. The data and physical examination of 188 patients who had a CT scan of the shoulder from 2018 to 2023 were retrospective analyses, including 107 patients (49 females, 58 males) with RCT and 81 patients (20 females, 61 males) with non-RCT. Using Three-dimensional computed tomography (3D-CT), parameters such as the AI, CSA, AHD, and LAA were compared between the RCT and non-RCT groups. Two independent assessors measured Each parameter from anterior views of the scapula. The inter- and intra-observer reliability was evaluated using the intraclass correlation coefficient (ICC). Additionally, the relationship between these parameters and the presence of rotator cuff tears was explored, and the predictive value of each parameter was assessed through receiver operating characteristic (ROC) analysis. The results showed excellent intra- and inter-observer reliability, with all ICC values above 0.75. Among these, the CSA exhibited the greatest measurement stability, with an intra-observer ICC of 0.929 and an inter-observer ICC of 0.911. Significant positive correlations were identified between the AI, CSA, and the presence of RCTs, with CSA exhibiting the strongest correlation (r = 0.629; P < 0.001). Additionally, significant negative correlations were found between the presence of RCTs and both AHD (–0.247) and LAA (–0.338; P < 0.001 for both). The ROC analysis revealed that the CSA is the most effective parameter for identifying the presence of RCT (area under the ROC curve. 0.857). The outcome of this study shows that AI, CSA, AHD, and LAA are independent factors associated with rotator cuff tears in the East African, particularly the Somali population. Specifically, larger AI, CSA, and smaller AHD and LAA are correlated with an increased likelihood of RCTs in this population. In patients with shoulder disease suspected of RCTs, using a 3D-CT scan to measure the CSA may be helpful, as it is the best predictor measurement. Not Applicable.

Background: Surgery is widely recognized as an effective treatment for Achilles tendon rupture; however, there remains debate regarding the optimal surgical approach. Purpose: To compare the biomechanical properties of 2 techniques, the H-loop knotless double-row (HLDR) suture repair and the Krackow suture repair, for Achilles tendon rupture in a cadaveric model. Study Design: Controlled laboratory study. Methods: Ten matched Achilles tendon specimens from 5 male and 5 female donors were obtained. Each specimen from a matched pair was randomly distributed to 1 of 2 repair groups, the HLDR group or the Krackow group. Tendon elongation was recorded after exposure to 10, 100, 200, 400, 600, 800, and 1000 load cycles. The gap distance after application of a 100-N force, the force needed to produce a 2-mm gap, and the load to failure were measured. All biomechanical properties were compared between the HLDR and Krackow groups using the paired t test. Results: The HLDR group consistently exhibited significantly less elongation than the Krackow group after exposure to the 7 load cycles ( P < .01 for all). In addition, the HLDR group exhibited a significantly smaller gap distance after applying a 100-N force (0.30 ± 0.02 vs 8.10 ± 0.46 mm for Krackow group), required significantly more force to generate a 2-mm gap (419.68 ± 39.48 vs 22.29 ± 3.40 N for the Krackow group), and had a significantly higher ultimate failure load (519.91 ± 57.29 vs 220.30 ± 19.27 N for the Krackow group) ( P < .01 for all). Conclusion: The study findings demonstrated that the HLDR technique had more advantages compared with the Krackow technique with regard to elongation after different cyclic loadings, gap distance after a 100-N load, force needed to produce a 2-mm gap, and load to failure in a cadaveric model. Clinical Relevance: The HLDR technique could be a viable option for Achilles tendon rupture repair.

Background Lateral, All-Round and All-Inside (LARAI) portal is a viewing or working portal for observing and repairing the lesions of the lateral meniscus. However, there are safety concerns about popliteal artery (PA) injuries during the procedure. This study aimed to assess the safe distance between the trajectory of the LARAI portal and PA. Materials and methods Both three-dimensional computed tomography (3D-CT) and cadavers were used to simulate the LARAI portal trajectory. In the 3D-CT study, between January 2020 and September 2020, 45 participants who underwent computed tomography angiography were included in the study. The shortest distance from the PA to the simulated trajectory needle (PS) was measured using 3D-CT. Mean −3SD −2 was calculated to assess the safety of the LARAI portal trajectory. If this value was more than zero, the trajectory was considered “safe.” In the cadaveric study, lower limbs from seven fresh-frozen cadavers were used to establish the “safe” trajectories of the LARAI portal, and the PS was measured. Results In the 3D-CT study, the longest PS ( P < 0.001) was found 20 mm lateral to the edge of the patellar tendon trajectory at 0 mm from the posterior cruciate ligament (PCL). Safe trajectories were also found 10 mm, 15 mm, and 20 mm lateral to the edge of the patellar tendon at 0 mm from the PCL, as well as the 20 mm lateral to the edge of the patellar tendon at 3 mm from the PCL. The cadaveric study showed that the average PS of all safe trajectories closely adjoined to PCL was greater than 14 mm. Conclusions The LARAI portal trajectory in the “figure of four” is safe, and the optimal insertion point is 10–20 mm lateral to the edge of the patellar tendon and closely adjoined to the posterolateral margin of the PCL at knee joint line level. Level of evidence Level IV.

Background: The Critical Shoulder Angle Related Acromion Morphological Parameter (CSA- RAMP) is a valuable tool in the analyzing the etiology of the rotator cuff tears (RCTs). However, its clinical application has been limited by the time-consuming and prone to inter- and intra-user variability of the measurement process.Objectives: To develop and validate a deep learning algorithm for fully automated assessment of shoulder anteroposterior radiographs associated with RCTs and calculation of CSA-RAMP.Methods: Retrospective analysis was conducted on radiographs obtained from computed tomography (CT) scans and X-rays performed between 2018 and 2020 at our institution. The development of the system involved the utilization of digitally reconstructed radiographs (DRRs) generated from each CT scan. The system's performance was evaluated by comparing it with manual and semiautomated measurements on two separate test datasets: dataset I (DRRs) and dataset II (X-rays). Standard metrics, including mean average precision (AP), were utilized to assess the segmentation performance. Additionally, the consistency among fully automated, semiautomated, and manual measurements was comprehensively evaluated using the Pearson correlation coefficient and BlandAltman analysis.Results: A total of 1080 DRRs generated from 120 consecutive CT scans and 159 X-ray films were included in the study. The algorithm demonstrated excellent segmentation performance, with a mean AP of 57.67 and an AP50 of 94.31. Strong inter-group correlations were observed for all CSA-RAMP measurements in both test datasets I (automated versus manual, automated versus semiautomated, and semiautomated versus manual; r = [0.990---0.997], P < 0.001) and dataset II (r = [0.984---0.995], P < 0.001). Bland-Altman analysis revealed low bias for all CSA-RAMP measurements in both test datasets I and II, except for CD (with a maximum bias of 2.49%).Conclusions: We have successfully developed a fully automated algorithm capable of rapidly and accurately measuring CSA-RAMP on shoulder anteroposterior radiographs. A consistent automated CSA- RAMP measurement system may accelerate powerful and precise studies of disease biology in future large cohorts of RCTs patients.

The aim of this study is to develop a machine learning model to identify important clinical features related to rotator cuff tears (RCTs) using explainable artificial intelligence (XAI) for efficiently predicting outpatients with RCTs. A retrospective review of a local clinical registry dataset was performed to include patients with shoulder pain and dysfunction who underwent questionnaires and physical examinations between 2019 and 2022. RCTs were diagnosed by shoulder arthroscopy. Six machine-learning algorithms (Stacking, Gradient Boosting Machine, Bagging, Random Forest, Extreme Gradient Boost (XGBoost), and Adaptive Boosting) were developed for the prediction. The performance of the models was assessed by the area under the receiver operating characteristic curve (AUC), Brier scores, and Decision curve. The interpretability of the predicted outcomes was evaluated using Shapley additive explanation (SHAP) values. A total of 1684 patients who completed questionnaires and clinical tests were included, and 417 patients with RCTs underwent shoulder arthroscopy. In six machining learning algorithms for predicting RCTs, the accuracy, AUC values, and Brier scores were in the range of 0.81–0.86, 0.75–0.92, and 0.15–0.19, respectively. The XGBoost model showed superior performance with accuracy, AUC, and Brier scores of 0.85(95