Durable immunomodulatory hierarchical patch for rotator cuff repairing.

Degradable rotator cuff patches, followed over five years, have been observed to exhibit high re-tear rates exceeding 50%, which is attributed to the inability of degradable polymers alone to restore the post-rotator cuff tear (RCT) inflammatory niche. Herein, poly(ester-ferulic acid-urethane)urea (PEFUU) was developed, featuring prolonged anti-inflammatory functionality, achieved by the integration of ferulic acid (FA) into the polyurethane repeating units. PEFUU stably releases FA in vitro, reversing the inflammatory niche produced by M1 macrophages and restoring the directed differentiation of stem cells. Utilizing PEFUU, hierarchical composite nanofiber patch (HCNP) was fabricated, simulating the natural microstructure of the tendon-to-bone interface with an aligned-random alignment. The incorporation of enzymatic hydrolysate derived from decellularized Wharton jelly tissue into the random layer could further enhance cartilage regeneration at the tendon-to-bone interface. Via rat RCT repairing model, HCNP possessing prolonged anti-inflammatory properties uniquely facilitated physiological healing at the tendon-to-bone interface's microstructure. The alignment of fibers was restored, and histologically, the characteristic tripartite distribution of collagen I - collagen II - collagen I was achieved. This study offers a universal approach to the functionalization of degradable polymers and provides a foundational reference for their future applications in promoting the in vivo regeneration of musculoskeletal tissues.

Double Level Knee Derotational Osteotomy Yields Better Postoperative Outcomes than Tibial Tubercle Transfer Combined with Medial Patellofemoral Ligament Reconstruction in Patients with Recurrent Patellar Instability and Severe Malrotation.

PURPOSE: To assess the postoperative outcomes of double level knee derotational osteotomy (KDRO) combined with medial patellofemoral ligament reconstruction (MPFLR), and to compare it with tibial tuber transfer (TTT) and MPFLR without derotational osteotomy in patients with recurrent patellar instability (RPI) and a marked torsional deformity. METHODS: From March 2020 to December 2021, patients with torsion deformity (combined femoral torsion and tibial torsion ≥ 30°) were retrospectively included. The minimum follow-up time was 18 months. Patients received KDRO and MPFLR were categorized into KDRO group and patients received a combined TTT and MPFLR were categorized into control group. Preoperative and postoperative clinical symptoms, patient-reported outcomes (PROs) (Kujala, visual analogue scale [VAS], Lysholm, International Knee Documentation Committee [IKDC], Tegner, and Knee Injury and Osteoarthritis Outcome [KOOS] scores) and imaging parameters (femoral torsion, tibial torsion, patellar height, femoral trochlear dysplasia, congruence angle, patellar tilt angle, lateral patellar angle, lateral patellar translation, and tibial tubercle-trochlear groove distance) were analyzed. RESULTS: In all, 36 patients were included with 18 in KDRO group and 18 in control group. The mean follow-up time was 30 (range 21-39) months. At the latest follow-up, no patient experienced re-dislocation in either group. Except for the femoral torsion and tibial torsion in the control group, postoperative imaging parameters were significantly reduced to the normal range. KDRO group has a lower patellar tilt angle (P=.043, effect size 0.64). All clinical scores in both groups significantly improved postoperatively. KDRO group has better functional scores than control group except the KOOS daily living activities subscore and the KOOS sports and recreation subscore. More proportions of patients in KDRO group met the minimal clinically important difference (MCID) for most PROs than control group. Eight patients (44%) in the control group complained of postoperative anterior knee pain, compared with 1 patient (6%) in KDRO group (P=.018). CONCLUSION: KDRO combined with MPFLR was associated with better postoperative outcomes than TTT combined with MPFLR in patients with RPI and a torsion deformity.

Intra-Articular Platelet-Rich Plasma Injection After Anterior Cruciate Ligament Reconstruction: A Randomized Clinical Trial.

Importance: Platelet-rich plasma (PRP) has been considered a promising treatment for musculoskeletal disorders. The effects of PRP on clinical outcomes of anterior cruciate ligament reconstruction (ACLR) are controversial. Objective: To compare subjective outcomes and graft maturity in patients undergoing ACLR with and without postoperative intra-articular PRP injection. Design, Setting, and Participants: This surgeon- and investigator-masked randomized clinical trial included patients treated at a national medical center in China who were aged 16 to 45 years and scheduled to undergo ACLR. Participants were enrolled between March 21, 2021, and August 18, 2022, and followed up for 12 months, with the last participant completing follow-up on August 28, 2023. Interventions: Participants were randomized 1:1 to the PRP group (n = 60), which received 3 doses of postoperative intra-articular PRP injection at monthly intervals, or to the control group (n = 60), which did not receive postoperative PRP injection. Both groups had the same follow-up schedule. Main Outcomes and Measures: The primary outcome was the mean score for 4 subscales of the Knee Injury and Osteoarthritis Outcome Score (KOOS4) (range, 0-100, with higher scores indicating better knee function and fewer symptoms) at 12 months postoperatively. Secondary outcomes were patient-reported outcomes, graft maturity (on magnetic resonance imaging), and physical examinations at 3, 6, and 12 months. Results: Among the 120 randomized participants (mean [SD] age, 29.0 [8.0] years; 84 males [70%]), 114 (95%) were available for the primary outcome analysis. The mean KOOS4 scores at 12 months were 78.3 (SD, 12.0; 95% CI, 75.2-81.4) in the PRP group and 76.8 (SD, 11.9; 95% CI, 73.7-79.9) in the control group (adjusted mean between-group difference, 2.0; 95% CI, -2.3 to 6.3; P = .36). Secondary outcomes were not statistically significantly different between the 2 groups except for sports and recreation level and graft maturity at 6 months. Intervention-related adverse events included pain at the injection site and knee swelling after injection. Conclusions and Relevance: In this randomized clinical trial among patients undergoing ACLR, the addition of postoperative intra-articular PRP injection did not result in superior improvement of knee symptoms and function at 12 months compared with no postoperative injection. Further studies are required to determine appropriate indications for PRP in musculoskeletal disorders. Trial Registration: Chinese Clinical Trial Registry Identifier: ChiCTR2000040262.

Janus Membranes Patch Achieves High-Quality Tendon Repair: Inhibiting Exogenous Healing and Promoting Endogenous Healing.

The imbalance between endogenous and exogenous healing is the fundamental reason for the poor tendon healing. In this study, a Janus patch was developed to promote endogenous healing and inhibit exogenous healing, leading to improved tendon repair. The upper layer of the patch is a poly(dl-lactide-co-glycolide)/polycaprolactone (PLGA/PCL) nanomembrane (PMCP-NM) modified with poly(2-methylacryloxyethyl phosphocholine) (PMPC), which created a lubricated and antifouling surface, preventing cell invasion and mechanical activation. The lower layer is a PLGA/PCL fiber membrane loaded with fibrin (Fb) (Fb-NM), serving as a temporary chemotactic scaffold to regulate the regenerative microenvironment. In vitro, the Janus patch effectively reduced 92.41% cell adhesion and 79.89% motion friction. In vivo, the patch inhibited tendon adhesion through the TGF-ß/Smad signaling pathway and promoted tendon maturation. This Janus patch is expected to provide a practical basis and theoretical guidance for high-quality soft tissue repair.

Application study of surgical instruments information management system in sports medicine specialty.

The management of surgical instruments is related to the safety and efficiency of surgical operations, and a surgical instruments information management system (SIIMS) has been developed. The aim of the current study is to explore the application value of the SIIMS in sports medicine specialty. A set of self-developed SIIMS for sports medicine surgeries was applied to the study. The application value of the SIIMS was verified by comparing the safety and efficiency of instrument manipulation before and after its application, with instrument accidents, instrument repair rate, instrument scrap rate and instrument use efficiency as indicators. Through the application of the SIIMS, the incidence of surgical instrument accidents decreased from 3.7 times to 1.8 times (P = 0.02), the number of instrument repair decreased from 7.7 times to 2.9 times (P = 0.00), and the number of scrapped instruments decreased from 5.1 to 2.3 (P = 0.03), when referred to per thousand operations. Before and after the application of the SIIMS, the average instrument use efficiency was 74.0% ± 3.3% and 88.2% ± 4.4%, respectively, with statistically significant difference (P = 0.00). The application of the SIIMS in sports medicine specialty is helpful to the fine management of surgical instruments, improve surgical safety and instrument use efficiency.

Impact of sex and age on the lateralisation of the tibial tubercle in normal paediatric and adolescent populations.

PURPOSE: Numerous methods have been proposed to characterise tubercle lateralisation. However, their normal values and related changes remain unclear. Accordingly, it was aimed to determine the potential sex and age effects and determined the optimal individualised method of diagnosing lateralisation of the tibial tubercle in patients with recurrent patellar dislocation (RPD). METHODS: Measurements included the tibial tubercle-trochlear groove (TT-TG) distance, tibial tubercle-posterior cruciate ligament (TT-PCL) distance and tibial tubercle lateralisation (TTL); and the proximal tibial width (PTW), trochlear width (TW) and trochlear dysplasia index (TDI), for adjustment. A two-way analysis of variance was used to determine the effect of age, sex and their interaction within the normal group. When the age effect was statistically significant, a nonlinear regression was created. Areas under the receiver-operating characteristic curve (AUCs) were calculated to assess diagnostic accuracy. RESULTS: A total of 277 normal participants (mean [SD] age, 13.5 [2.6] years; 125 [45.1%] female) and 227 patients with RPD (mean [SD] age, 13.5 [2.6] years; 161 [58.1%] female) were analysed. It was found that in the normal group, in patients aged 7-10, TT-PCL distance (p = 0.006), TTL (p = 0.007) and TT-PCL/PTW (p < 0.001) were significantly larger in females than in males. A significant sex effect was also detected on TT-TG/TW (p = 0.014). TT-TG distance, TT-PCL distance, TTL and TT-PCL/PTW (in male patients) approached an established normal adult value of 12.3 mm, 20.9 mm, 0.64 and 0.28, respectively, with increasing age (p < 0.001). The AUC was greater for TT-TG/TDI and TT-TG/TW (p ≤ 0.01) and TT-TG/TDI outperformed TT-TG/TW in patients aged 15-18 (p = 0.004). CONCLUSIONS: Tubercle lateralisation increased with age and was affected by sex, with the exception of TT-TG distance and TT-TG/TDI. TT-TG/TDI is the optimal method of diagnosing a lateralized tibial tubercle in patients with RPD. These findings assist with the evaluation of tubercle lateralisation in that they provide a proper protocol for paediatric and adolescent populations with RPD; and thus, will help determine whether medial tubercle transfer should be included among the tailored surgical procedures considered for the treatment of patients with RPD. LEVEL OF EVIDENCE: Level III.

Robotic-assisted anatomic anterior cruciate ligament reconstruction: a comparative analysis of modified transtibial and anteromedial portal techniques in cadaveric knees.

Introduction: This study employed surgical robot to perform anatomic single-bundle reconstruction using the modified transtibial (TT) technique and anteromedial (AM) portal technique. The purpose was to directly compare tunnel and graft characteristics of the two techniques. Methods: Eight cadaveric knees without ligament injury were used in the study. The modified TT and AM portal technique were both conducted under surgical robotic system. Postoperative data acquisition of the tunnel and graft characteristics included tibial tunnel position, tunnel angle, tunnel length and femoral tunnel-graft angle. Results: The mean tibial tunnel length of the modified TT technique was significantly shorter than in the AM portal technique (p < 0.001). The mean length of the femoral tunnel was significantly longer for the modified TT technique than for the AM portal technique (p < 0.001). The mean coronal angle of the tibial tunnel was significantly lower for the modified TT technique than for the AM portal technique (p < 0.001). The mean coronal angle of the femoral tunnel was significantly lower for the AM portal technique than for the modified TT technique (p < 0.001). The AM portal technique resulted in a graft bending angle that was significantly more angulated in the coronal (p < 0.001) and the sagittal planes (p < 0.001) compared with the modified TT technique. Discussion: Comparison of the preoperative planning and postoperative femoral tunnel positions showed that the mean difference of the tunnel position was 1.8 ± 0.4 mm. It suggested that the surgical navigation robot could make predictable tunnel position with high accuracy. The findings may support that the modified TT technique has benefits on femoral tunnel length and obliquity compared with AM portal technique. The modified TT technique showed a larger femoral tunnel angle in the coronal plane than the AM portal technique. Compared with the modified TT technique, the more horizontal trajectory of the femoral tunnel in the AM portal technique creates a shorter femoral tunnel length and a more acute graft bending angle.

Healthy Tendon Stem Cell-Derived Exosomes Promote Tendon-To-Bone Healing of Aged Chronic Rotator Cuff Tears by Breaking the Positive-Feedback Cross-Talk between Senescent Tendon Stem Cells and Macrophages through the Modulation of Macrophage Polarization.

The re-tear rate of rotator cuff tears (RCT) after surgical repair is high, especially in aged patients with chronic tears. Senescent tendon stem cells (s-TSCs) generally exist in aged and chronically torn rotator cuff tendons and are closely associated with impaired tendon-to-bone healing results. The present study found a positive feedback cross-talk between s-TSCs and macrophages. The conditioned medium (CM) from s-STCs can promote macrophage polarization mainly toward the M1 phenotype, whose CM reciprocally accelerated further s-TSC senescence. Additional healthy tendon stem-cells derived exosomes (h-TSC-Exos) can break this positive feedback cross-talk by skewing macrophage polarization from the M1 phenotype to the M2 phenotype, attenuating s-TSCs senescence. S-TSC senescence acceleration or attenuation effects induced by M1 or M2 macrophages are associated with the inhibition or activation of the bone morphogenetic protein 4 signaling pathway following RNA sequencing analysis. Using an aged-chronic rotator cuff tear rat model, it is found that h-TSC-Exos can shift the microenvironment in the tendon-to-bone interface from a pro-inflammatory to an anti-inflammatory type at the acute postoperative stage and improve the tendon-to-bone healing results, which are associated with the rejuvenated s-TSCs. Therefore, this study proposed a potential strategy to improve the healing of aged chronic RCT.

Clinical and Radiological Outcomes After Combined ACL and MPFL Reconstruction Versus Isolated ACL Reconstruction for ACL Injury With Patellar Instability.

BACKGROUND: An anterior cruciate ligament (ACL) injury accompanied by patellar instability (PI) is a topic that has gained orthopaedic surgeons' attention recently. Untreated PI is reportedly associated with worse clinical outcomes after isolated ACL reconstruction (ACLR) in patients after an ACL injury with PI. Nevertheless, the appropriate surgical approach and its long-term therapeutic effects in these patients remain unclear. PURPOSE: (1) To compare the clinical and radiological outcomes between isolated ACLR (iACLR) and combined ACLR and medial patellofemoral ligament reconstruction (cAMR) in patients after an ACL injury with PI and (2) to explore the correlations between these 2 procedures and clinical and radiological outcomes. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 106 patients diagnosed with an ACL injury accompanied by PI between January 2016 and April 2021 were analyzed in this study. There were 34 patients excluded because of missing postoperative radiological data. Among the remaining 72 patients, 34 patients underwent iACLR, while 38 patients underwent cAMR. Demographic characteristics, intraoperative findings, and patient-reported outcomes (Lysholm score, subjective International Knee Documentation Committee score, and Tegner activity score) were prospectively collected. Patellar alignment parameters and worsening patellofemoral osteoarthritis (PFOA) features (evaluated with the modified Whole-Organ Magnetic Resonance Imaging Score) were analyzed longitudinally on magnetic resonance imaging. The Kujala score was used to evaluate the functional recovery of the patellofemoral joint, and redislocations of the patella were prospectively recorded. Finally, multivariate logistic regression analysis was used to explore the correlations between these 2 procedures and clinical (not achieving the minimal detectable change [MDC] for the Lysholm score) and radiological (worsening PFOA features) outcomes. RESULTS: The mean follow-up duration was 28.9 ± 6.2 and 27.1 ± 6.8 months for the iACLR and cAMR groups, respectively (P = .231). Significantly higher Lysholm scores (88.3 ± 9.9 vs 82.1 ± 11.1, respectively; P = .016) and subjective International Knee Documentation Committee scores (83.6 ± 11.9 vs 78.3 ± 10.2, respectively; P = .046) were detected in the cAMR group compared with the iACLR group postoperatively. The rates of return to preinjury sports were 20.6% and 44.7% in the iACLR and cAMR groups, respectively (difference, 24.1% [95% CI, 3.3%-45.0%]; P = .030). Moreover, the rates of worsening PFOA features were 44.1% and 18.4% in the iACLR and cAMR groups, respectively (difference, 25.7% [95% CI, 4.9%-46.4%]; P = .018). In addition, significantly higher Kujala scores (87.9 ± 11.3 vs 80.1 ± 12.0, respectively; P = .006), lower redislocation rates (0.0% vs 11.8%, respectively; difference, 11.8% [95% CI, 0.9%-22.6%]; P = .045), and significantly better patellar alignment were detected in the cAMR group compared with the iACLR group postoperatively. Furthermore, multivariate logistic regression analysis determined that iACLR and partial lateral meniscectomy were significantly correlated with not achieving the MDC for the Lysholm score and worsening PFOA features in our study population. CONCLUSION: In patients after an ACL injury with PI, cAMR yielded better clinical and radiological outcomes compared with iACLR, with better patellar stability and a lower proportion of worsening PFOA features. Furthermore, not achieving the MDC for the Lysholm score and worsening PFOA features were significantly correlated with iACLR and partial lateral meniscectomy. Our study suggests that cAMR may be a more appropriate procedure for patients after an ACL injury with PI, which warrants further high-level clinical evidence.

Biomechanical Analysis Reveals Shoulder Instability With Bipolar Bone Loss Is Best Treated With Dynamic Anterior Stabilization for On-Track Lesions and with Remplissage for Off-Track Lesions.

PURPOSE: To compare the biomechanical effects of augmenting Bankart repair (BR) with either remplissage or dynamic anterior stabilization (DAS) in the treatment of anterior shoulder instability with on-track or off-track bipolar bone loss. METHODS: Eight fresh-frozen cadaveric shoulders were tested at 60° of glenohumeral abduction in the intact, injury, and repair conditions. Injury conditions included 15% glenoid bone loss with an on-track or off-track Hill-Sachs lesion as previously recommended. Repair conditions included isolated BR, BR with remplissage, and BR with DAS (long head of biceps transfer). The glenohumeral stability was assessed by measuring the anterior translation under 0, 10, 20, 30, 40, 50 N load and maximum load without causing instability at mid-range (60°) and end-range (90°) external rotation (ER). Maximum range of motion (ROM) was measured by applying a 2.2-N·m torque in passive ER and internal rotation. RESULTS: Isolated BR failed to restore native glenohumeral stability in both on-track and off-track bipolar bone loss models. Both remplissage and DAS significantly decreased the anterior instability in the bipolar bone loss models, showing better restoration than the isolated BR. In the on-track lesions, DAS successfully restored native glenohumeral stability and mobility, whereas remplissage significantly decreased anterior translation without load (-2.12 ± 1.07 mm at 90° ER, P = .003; -1.98 ± 1.23 mm at 60° ER, P = .015). In the off-track lesions, remplissage restored native glenohumeral stability but led to significant ROM limitation (-8.6° ± 2.3° for internal rotation, P < .001; -13.9° ± 6.2° for ER, P = .003), whereas DAS failed to restore native stability at 90° ER regarding the increased anterior translation under 50 N (4.10 ± 1.53 mm, P < .001) and decreased maximum load (-13.8 ± 9.2 N, P = .021). CONCLUSIONS: At time-zero, both remplissage and DAS significantly reduced residual anterior instability compared with isolated BR in the bipolar bone loss models and restored the native glenohumeral stability under most translational loads. However, remplissage could decrease the anterior translation without load for on-track lesions and may restrict ROM for off-track lesions, whereas DAS failed to restore native stability under high translational loads for off-track lesions. CLINICAL RELEVANCE: DAS could be recommended to treat on-track bipolar bone loss with less biomechanical adverse effects, whereas remplissage might be the preferred procedure to address off-track bipolar bone loss for better stability.

Synthesis of sulfinamides via photocatalytic alkylation or arylation of sulfinylamine.

Sulfinamides are a versatile class of compounds that find applications in both organic synthesis and pharmaceuticals. Here we developed an efficient photocatalytic approach for the convenient preparation of sulfinamides. Commercially available potassium trifluoro(organo)borates and readily available sulfinyl amines are rationally used and converted to a series of alkyl or aryl sulfinamides in moderate to high yields. The reaction allows for the gram-scale preparation of sulfinamides. Moreover, sulfonimidamides, sulfonimidate esters and sulfonyl amides could be obtained in one pot.

Characterization of the CT-based risk factors for concomitant patellofemoral instability in patients with anterior cruciate ligament injury.

OBJECTIVES: Underestimation of concomitant patellofemoral instability in patients with anterior cruciate ligament (ACL) injury has aroused extensive attention. However, the characteristics of the combined injury is not well recognized. Hence, we aimed to characterize the features of the combined injury, and determine the radiographic risk factors. METHODS: Fifteen radiological parameters were identified after discussion and pilot-tested. Radiographic measurements were compared using the analysis of variance model with Tukey post hoc analysis. A stepwise binomial logistic regression was performed and a nomogram model combining the significant risk factors was created. The model performance was validated by C-index, calibration plot, and decision curve. RESULTS: A total of 204 patients (mean [SD] age, 25.1 [6.7] years; 108 [52.9%] male) were included. The final model was updated through regression analysis using 4 parameters as significant risk factors: lateral femoral condyle ratio (OR (95% CI), 1.194 (1.023 to 1.409)), medial anterior tibial subluxation (mATS) (OR (95% CI), 1.234 (1.065 to 1.446)), medial posterior plateau tibial angle (mPPTA) (OR (95% CI), 1.266 (1.088 to 1.500)), and trochlear depth (OR (95% CI), 0.569 (0.397 to 0.784)). C-index for the nomogram was 0.802 (95% CI, 0.731 to 0.873) and was confirmed to be 0.784 through bootstrapping validation. Calibration plot established a good agreement between prediction and observation. Decision curve analysis showed that if threshold probability was over 10%, using the nomogram adds more benefit than either all or none scheme. CONCLUSIONS: Lateral femoral condyle ratio, mATS, mPPTA, and trochlear depth are strong adverse predictors of patellofemoral instability in patients with ACL injury. CLINICAL RELEVANCE: This study characterizes the radiological features of the combined injury. Patellofemoral instability should be noted when treating ACL injuries. KEY POINTS: • The radiological characteristics of the combined ACL injury and patellofemoral instability is not well recognized. • Lateral femoral condyle ratio, mATS, mPPTA, and trochlear depth are predominant risk factors for patellofemoral instability in patients with ACL injury. • Patellofemoral instability should be noted when treating ACL injuries.

The Value of Minimal Clinically Important Difference, Substantial Clinical Benefit, and Patient-Acceptable Symptomatic State for Commonly Used Patient-Reported Outcomes in Recurrent Patellar Instability Patients After Medial Patellofemoral Ligament Reconstruction and Tibial Tubercle Transfer.

PURPOSE: To identify the minimal clinically important difference (MCID), substantial clinical benefit (SCB) and patient-acceptable symptomatic state (PASS) for commonly used patient-reported outcomes (PROs) in recurrent patellar instability patients after medial patellofemoral ligament reconstruction (MPFLR) and tibial tubercle transfer (TTT), and to determine the impact of potential prognostic factors on the likelihood of achieving these values. METHODS: From April 2015 to February 2021, patients who underwent MPFLR and TTT were retrospectively reviewed. PROs included Kujala, Knee Injury and Osteoarthritis Outcome (KOOS), Lysholm, International Knee Documentation Committee (IKDC), and Tegner score. Relevant anchor questions were provided. A distribution- or anchor-based method was adopted to determine the MCID, SCB, and PASS. Minimal detectable change (MDC) was included to confirm the validity. Univariate regression analyses were conducted to determine the potential prognostic factors. RESULTS: One hundred forty-two patients were included. The MCID were 9.1 (Kujala), 11.1 (Lysholm), 0.9 (Tegner), 9.9 (IKDC), 9.0 (KOOS-Pain), 10.8 (KOOS-Symptoms), 10.0 (KOOS-Activities of Daily Living [ADL]), 17.8 (KOOS-Sports and Recreation [Sports/Rec]), and 12.7 (KOOS-Quality of Life [QoL]). The SCB were 14.5 (Kujala), 12.5 (Lysholm), 1.5 (Tegner), 14.5 (IKDC), 13.9 (KOOS-Pain), 14.3 (KOOS-Symptoms), 18.4 (KOOS-ADL), 47.5 (KOOS-Sports/Rec), and 15.0 (KOOS-QoL). The PASSs were 85.5 (Kujala), 75.5 (Lysholm), 3.5 (Tegner), 73.2 (IKDC), 87.5 (KOOS-Pain), 73.2 (KOOS-Symptoms), 92.0 (KOOS-ADL), 77.5 (KOOS-Sports/Rec), and 53.1 (KOOS-QoL). All SCBs were valid except KOOS-QoL. All MCIDs were valid at the 95% confidence interval (CI) except KOOS scores, the majority of which were valid at the 90% CI. A younger age was an independent prognostic factor of reaching PASS for Lysholm, IKDC, Tegner, and KOOS-ADL score. A higher baseline score was a negative prognostic factor for achieving MCID or SCB but had a slightly positive influence on the achievement of PASS. CONCLUSIONS: This study established the MCID, SCB, and PASS for commonly used PROs and confirmed their validity in recurrent patellar instability patients after MPFLR and TTT. Younger age and lower baseline scores were prognostic factors of achieving MCID and SCB, whereas patients with higher baseline scores were more likely to report satisfaction. LEVEL OF EVIDENCE: Level III, retrospective comparative prognostic trial.

A Deep Learning Model Enhances Clinicians' Diagnostic Accuracy to More Than 96% for Anterior Cruciate Ligament Ruptures on Magnetic Resonance Imaging.

PURPOSE: To develop a deep learning model to accurately detect anterior cruciate ligament (ACL) ruptures on magnetic resonance imaging (MRI) and to evaluate its effect on the diagnostic accuracy and efficiency of clinicians. METHODS: A training dataset was built from MRIs acquired from January 2017 to June 2021, including patients with knee symptoms, irrespective of ACL ruptures. An external validation dataset was built from MRIs acquired from January 2021 to June 2022, including patients who underwent knee arthroscopy or arthroplasty. Patients with fractures or prior knee surgeries were excluded in both datasets. Subsequently, a deep learning model was developed and validated using these datasets. Clinicians of varying expertise levels in sports medicine and radiology were recruited, and their capacities in diagnosing ACL injuries in terms of accuracy and diagnosing time were evaluated both with and without artificial intelligence (AI) assistance. RESULTS: A deep learning model was developed based on the training dataset of 22,767 MRIs from 5 centers and verified with external validation dataset of 4,086 MRIs from 6 centers. The model achieved an area under the receiver operating characteristic curve of 0.987 and a sensitivity and specificity of 95.1%. Thirty-eight clinicians from 25 centers were recruited to diagnose 3,800 MRIs. The AI assistance significantly improved the accuracy of all clinicians, exceeding 96%. Additionally, a notable reduction in diagnostic time was observed. The most significant improvements in accuracy and time efficiency were observed in the trainee groups, suggesting that AI support is particularly beneficial for clinicians with moderately limited diagnostic expertise. CONCLUSIONS: This deep learning model demonstrated expert-level diagnostic performance for ACL ruptures, serving as a valuable tool to assist clinicians of various specialties and experience levels in making accurate and efficient diagnoses. LEVEL OF EVIDENCE: Level III, retrospective comparative case series.

Decellularization-Based Modification Strategy for Bioactive Xenografts Promoting Tendon Repair.

Xenografts have emerged as a promising option for severe tendon defects treatment. However, despite undergoing decellularization, concerns still remain regarding the immunogenicity of xenografts. Because certain components within the extracellular matrix also possess immunogenicity. In this study, a novel strategy of post-decellularization modification aimed at preserving the endogenous capacity of cells on collagen synthesis to mask antigenic epitopes in extracellular matrix is proposed. To implement this strategy, a human-derived rosiglitazone-loaded decellularized extracellular matrix (R-dECM) is developed. R-dECM can release rosiglitazone for over 7 days in vitro. By suppressing M1 macrophage polarization, R-dECM protects the migration and collagen synthesis abilities of tendon-derived stem cells (TDSCs), while also stabilizing the phenotype of M2 macrophages in vitro. RNA sequencing reveals R-dECM can mitigate the detrimental crosstalk between TDSCs and inflammatory cells. When applied to a rat patellar tendon defect model, R-dECM effectively inhibits early inflammation, preventing chronic inflammation. Its duration of function far exceeds the release time of rosiglitazone, implying the establishment of immune evasion, confirming the effectiveness of the proposed strategy. And R-dECM demonstrates superior tendon repair outcomes compared to dECM. Thus, this study provides a novel bioactive scaffold with the potential to enhance the long-term clinical outcomes of xenogeneic tendon grafts.

Longitudinal Changes in Overall 3D Supraspinatus Muscle Volume and Intramuscular Fatty Infiltration After Arthroscopic Rotator Cuff Repair.

BACKGROUND: There is considerable debate regarding the longitudinal changes in overall rotator cuff (RC) muscle atrophy and intramuscular fatty infiltration (FI) following RC repair. We analyzed the longitudinal changes in overall 3D supraspinatus muscle volume and intramuscular FI (3D FI) to determine the effect of tear size and repair integrity on 3D muscle volume and intramuscular FI. METHODS: Forty-seven patients who underwent arthroscopic RC repair and had 6-point Dixon shoulder magnetic resonance imaging (MRI) preoperatively and 3 and 12 months postoperatively were enrolled. The 3D supraspinatus muscle volume and intramuscular FI were calculated at the 3 time points, and their changes over time were evaluated in the entire cohort as well as according to tear size and repair integrity. The agreement of the difference between time points among the patients was assessed by Bland-Altman analysis. RESULTS: In the cohort as a whole, there were no significant longitudinal changes in the 3D supraspinatus volume (19.65 ± 7.26 to 19.48 ± 7.46 cm 3 , p = 0.911) or 3D FI (17.18% ± 8.85% to 17.30% ± 9.18%, p = 0.977) from preoperatively to the final 12-month time point, overall and in the tear size and repair integrity subgroups. The 3D supraspinatus volume was significantly decreased at 3 months (17.39 ± 6.12 cm 3 , p < 0.001) but then increased again by 12 months (p < 0.001), reaching a value similar to the preoperative level. The 3D FI had a small increase at 3 months (18.18% ± 9.65%, p = 0.097) but subsequently decreased slightly again (p = 0.211), such that there were no significant longitudinal changes. The differences in the 3D supraspinatus volume and FI between these time points showed high agreement among patients. CONCLUSIONS: The overall 3D supraspinatus volume and 3D FI showed no longitudinal change between the preoperative baseline and the 12-month follow-up after arthroscopic RC repair. Tear size and repair integrity had no impact on the longitudinal patterns of muscle volume and intramuscular FI changes. The 3D supraspinatus volume decreased during the first 3 months but recovered to baseline at 12 months postoperatively; 3D FI was relatively stable throughout the 12 months of follow-up after repair. LEVEL OF EVIDENCE: Therapeutic Level II . See Instructions for Authors for a complete description of levels of evidence.

Prevalence and a correlation analysis of discoid meniscus and femoral trochlear dysplasia.

BACKGROUND: Discoid meniscus (DM) and femoral trochlear dysplasia (FTD) are common knee disorders. Both as congenital malformation, whether there is a connection between them is unclear and the research on their prevalence in the general population is inadequate. This study aimed to investigate the prevalence of FTD and DM in the general population through a large sample size, and to explore the relationship between them. STUDY DESIGN: Retrospective study. METHODS: Patients undergoing knee magnetic resonance imaging (MRI) examinations at our outpatient clinic were screened and 1003 patients were enrolled in DM group with 989 patients in non-DM (NDM) group. The type of DM and FTD was classified with Watanabe classification and Dejour's classification, respectively. The prevalence of FTD and DM in the general population and the relationship between them were evaluated. RESULTS: The prevalence of DM and FTD was 10.0% and 14.5%, respectively. The overall percentage of FTD was higher in DM group (P < 0.001). The DM group has a higher percentage of all types of FTD except type D (P < 0.05), and a higher percentage of both low- and high-grade FTD (P < 0.001). There were 633 cases of type I DM and 370 cases of type II DM. The overall percentage of FTD was not significantly different between the two types (P = 0.106). No significant difference was detected for all types of FTD except type B (P < 0.05). The Type I DM group has a significant higher percentage of high-grade FTD than Type II group (P < 0.05). CONCLUSION: Patients with a DM are more likely to have FTD regardless of the type of DM, while those with a type I DM are more prone to have a high grade FTD.

Micro-nano hierarchical scaffold providing temporal-matched biological constraints for tendon reconstruction.

Due to the limitations of tendon biology, high-quality tendon repair remains a clinical and scientific challenge. Here, a micro-nano hierarchical scaffold is developed to promote orderly tendon regeneration by providing temporal-matched biological constraints. In short, fibrin (Fb), which provides biological constraints, is loaded into poly (DL-lactide-co-glycolide) nanoyarns with suitable degradation cycles (Fb-loaded nanofiber yarns (Fb-NY)). Then further combined with braiding technology, temporary chemotactic Fb scaffolds with tendon extracellular matrix-like structures are obtained to initiate the regeneration process. At the early stage of healing (2 w), the regeneration microenvironment is regulated (inducing M2 macrophages and restoring the early blood supply necessary for healing) by Fb, and the alignment of cells and collagen is induced by nanoyarn. At the late healing stage (8 w), with the degradation of Fb-NY, non-functional vascular regression occurs, and the newborn tissues gradually undergo load-bearing remodeling, restoring the anvascularous and ordered structure of the tendon. In summary, the proposed repair strategy provides temporal-matched biological constraints, offering a potential pathway to reconstruct the ordered structure and function of tendons.

One-pot cascade synthesis of dibenzothiophene-based heterobiaryls from dibenzothiophene-5-oxide.

A sulfoxide directed C-H metalation/boration/B2Pin2 mediated reduction/Suzuki coupling process to synthesize 4-substituted dibenzothiophene (DBT) in one-pot from dibenzothiophene-5-oxide (DBTO) was developed. A variety of DBT-based heterobiaryls were prepared in satisfactory to good yields. A mechanism was proposed. The application of this methodology was demonstrated by synthesizing a luminescent material.

An environmentally benign protocol for the synthesis of sugar 1,2-orthoesters in poly(ethylene glycol) dimethyl ether (DMPE).

An environmentally benign procedure has been developed for the synthesis of sugar orthoesters using anhydrous sodium acetate in poly (ethylene glycol)dimethyl ether (DMPE). Various sugar orthoesers were prepared without using volatile organic solvent and quaternary ammonium salt. The sugar orthoesters were obtained in good to excellent yields.