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Context : In March 2020, public health concerns resulted in school closure throughout the United States . The prolonged sport cessation may affect knee injury risk in high school athletes. The purpose of this study was to describe and compare risk of knee injuries in high school athletes during 2019-2020 and 2020-2021 academic years, and stratify by gender, severity, mechanism of injury, injury type, and knee anatomic region . Design : Historical-prospective cohort study . Methods : This historical- prospective cohort study included 176 schools in 6 states matched by sport participation in control and COVID years from July 1, 2019 to June 30,2021. Injury rates per 1000 athletes per year were calculated with 95% confidence intervals. A negative binomial regression was performed to assess potential differences in knee injuries between academic years . Results: 94, 847 and 72,521 high school athletes participated in the 2019-2020(19-20) and 2020-2021 (20-21) seasons. Knee injury risk was higher in the 20-21 season (19-20: 28.89% [27.82-29.96-]; 20-21: 33.82% [32.50-35.14]). Risk increased for male athletes from 2019- 2020 to 2020-2021 (19-20: 29.42% [28.01-30.83]; 20-21 : 40.32% [38.89-41.75]). Female knee injury risk was similar between years (19-20: 25.78% [24.29-27.27]; 20-21: 26.03% [24.31-27.75]). Knee injuries increased by a ratio of 1.2 ([95% CI, 1.1- 1.3], P <.001) during 2020-2021. Conclusions,· Knee injury risk and relative risk increased among males in 2020-2021. Results indicate changes in knee injury risk following return from COVID shelter in place among high school athletes and implicate potential negative downstream effects of interrupted sports training and participation on high school injury risk. [ABSTRACT FROM AUTHOR]

Prior studies have explored the relationship between knee valgus and musculoskeletal variables to formulate injury prevention programs, primarily for females. Nonetheless, there is insufficient evidence pertaining to professional male soccer players. Here, the aim was to test the correlation of lateral trunk inclination, hip adduction, hip internal rotation, ankle dorsiflexion range of motion, and hip isometric strength with knee valgus during the single-leg vertical jump test. Twenty-four professional male soccer players performed a single-leg vertical hop test, hip strength assessments, and an ankle dorsiflexion range of motion test. A motion analysis system was employed for kinematic analysis. Maximal isometric hip strength and ankle dorsiflexion range of motion were tested using a handheld dynamometer and a digital inclinometer, respectively. The correlation of peak knee valgus with peak lateral trunk inclination was.43 during the landing phase (P =.04) and with peak hip internal rotation was −.68 (P <.001). For knee valgus angular displacement, only peak lateral trunk inclination presented a moderate positive correlation (r =.40, P =.05). This study showed that trunk and hip kinematics are associated with knee valgus, which could consequently lead to increased knee overload in male professional soccer players following a unilateral vertical landing test. [ABSTRACT FROM AUTHOR]

The hamstring plays an important role in reducing loads born by the anterior cruciate ligament. As anterior cruciate ligament injuries occur rapidly after ground contact, how the hamstring is activated prior to landing can influence injury risk. The purpose was to determine sex-related differences in hamstring activation immediately before landing and the effect of fatigue on "preactivation." Twenty-four participants (13 males and 11 females, age = 24.3 [6.5] y, mass = 72.2 [19.3] kg, height = 169 [9.7] cm) participated in this study. Participants completed a drop-vertical jump protocol before and after a lower body fatigue protocol. Hamstring electromyography (EMG) amplitude at 5 periods prior to landing, peak vertical ground reactions forces (in newtons/body weight), rate of loading (in body weight/second), and landing error scoring system were measured. Females had higher EMG amplitude before and after fatigue (P <.024), with decreased EMG amplitude for both sexes after fatigue (P =.025). There was no change on vertical ground reaction force, rate of loading, or landing error scoring system. Males and females demonstrated similar landing performance before and after fatigue but have different hamstring neuromuscular coordination strategies. The acute reduction in hamstring EMG amplitude following fatigue may increase loading on the anterior cruciate ligament. [ABSTRACT FROM AUTHOR]

PurposeTo develop a 3D phase modulated UTE adiabatic T1ρ (PM-UTE-AdiabT1ρ ) sequence for whole knee joint mapping on a clinical 3 T scanner.MethodsThis new sequence includes six major features: (1) a magnetization reset module, (2) a train of adiabatic full passage pulses for spin locking, (3) a phase modulation scheme (i.e., RF cycling pair), (4) a fat saturation module, (5) a variable flip angle scheme, and (6) a 3D UTE Cones sequence for data acquisition. A simple exponential fitting was used for T1ρ quantification. Phantom studies were performed to investigate PM-UTE-AdiabT1ρ 's sensitivity to compositional changes and reproducibility as well as its correlation with continuous wave-T1ρ measurement. The PM-UTE-AdiabT1ρ technique was then applied to five ex vivo and five in vivo normal knees to measure T1ρ values of femoral cartilage, meniscus, posterior cruciate ligament, anterior cruciate ligament, patellar tendon, and muscle.ResultsThe phantom study demonstrated PM-UTE-AdiabT1ρ 's high sensitivity to compositional changes, its high reproducibility, and its strong linear correlation with continuous wave-T1ρ measurement. The ex vivo and in vivo knee studies demonstrated average T1ρ values of 105.6 ± 8.4 and 77.9 ± 3.9 ms for the femoral cartilage, 39.2 ± 5.1 and 30.1 ± 2.2 ms for the meniscus, 51.6 ± 5.3 and 29.2 ± 2.4 ms for the posterior cruciate ligament, 79.0 ± 9.3 and 52.0 ± 3.1 ms for the anterior cruciate ligament, 19.8 ± 4.5 and 17.0 ± 1.8 ms for the patellar tendon, and 91.1 ± 8.8 and 57.6 ± 2.8 ms for the muscle, respectively.ConclusionThe 3D PM-UTE-AdiabT1ρ sequence allows volumetric T1ρ assessment for both short and long T2 tissues in the knee joint on a clinical 3 T scanner.

This document discusses a case of a painless knee mass in a young adult. The MRI showed a soft tissue lesion in the posterior recess of the knee, closely related to the anterior cruciate ligament. A provisional diagnosis of a complex ACL ganglion was made based on the MRI findings. However, an aspiration biopsy revealed a synovial sarcoma, a rare and aggressive soft tissue sarcoma. The document emphasizes the importance of histopathological analysis in cases of ganglion aspiration to avoid misdiagnosis. The management of synovial sarcoma involves surgical resection and, in some cases, radiotherapy or neoadjuvant chemoradiotherapy. [Extracted from the article]

Objectives: To evaluate the type and prevalence of associated injuries by using magnetic resonance imaging (MRI) in patients with anterior cruciate ligament (ACL) tears. Methods: Data from the Natural Corollaries and Recovery after ACL injury multicenter longitudinal cohort study were analyzed. Between May 2016 and October 2018, patients aged between 15 and 40 years, who had experienced an ACL tear within the last 6 weeks and sought medical attention at one of seven healthcare clinics in Sweden, were invited to participate. The mean time from injury to MRI was 19.6 ± 15.2 days. An orthopedic knee surgeon and a musculoskeletal radiologist reviewed all the MRI scans. The following structures were assessed: posterior cruciate ligament (PCL), medial collateral ligament (MCL) complex, lateral collateral ligament (LCL), popliteus tendon, medial meniscus (MM), lateral meniscus (LM), and cartilage. In addition, the presence of bone bruising, impaction fractures in the lateral femoral condyle (LFC) or posterolateral tibia (PLT), and Segond fractures were also assessed. Results: A total of 254 patients (48.4% males) with a mean age of 25.4 ± 7.1 years were included. The prevalence of associated injuries was as follows: PCL (0.4%), MCL {41.3% [superficial MCL and deep MCL (dMCL) 16.5%; isolated dMCL 24.8%]}, LCL (2.4%), MM (57.4%), LM (25.2%), cartilage (15.0%), bone bruising (92.9%), impaction fracture in the LFC (45.7%) and PLT (4.7%), and Segond fracture (7.5%). Conclusions: The prevalence of associated injuries in patients with ACL tears was high. The findings reported in this study may serve as a reference tool for orthopedic surgeons and radiologists in the diagnosis of associated injuries using MRI in patients with ACL tears. [ABSTRACT FROM AUTHOR]

Introduction Anterior Cruciate Ligament (ACL) injuries continue to be a major source of morbidity in gymnastics. The gold standard is to perform an ACL Reconstruction (ACLR). However, injuries to the proximal femoral attachment of the ACL have demonstrated an ability to regenerate. An alternative surgical intervention to the ACLR in this ACL tear subgroup is an ACL repair. The purpose of this case report is to provide a rehabilitation progression for a female gymnast after an ACL repair with Internal Brace Ligament Augmentation (IBLA). Case Description The subject was a 16-year-old female who presented with a Sherman Type 1 proximal avulsion of her ACL. She underwent an ACL repair with IBLA. Physical therapy interventions followed a sequential and multi-phased approach based on time for tissue physiologic healing and individual progression. Patient reported outcomes including the International Knee Documentation Committee (IKDC), the Anterior Cruciate Ligament Return to Sport After Injury (ACL-RSI) and the Optimal Screening for Prediction of Referral and Outcome Yellow Flag (OSPRO-YF) were assessed in conjunction with isokinetic strength and hop performance testing to determine return to sport readiness. Outcomes The subject completed 42 sessions over the course of 26 weeks in addition to a home exercise program. At return to sport, clinically meaningful improvement was observed in patient reported outcomes including the IKDC, ACL-RSI, and OSPRO-YF. Additionally, strength and hop performance surpassed established thresholds of clinical significance. The subject returned to sport at six months post-operatively. Conclusion The subject in this case report returned to full participation in gymnastics six months after an ACL repair with internal bracing following a sequential and multi-phased rehabilitation. The primary ACL repair with IBLA appeared beneficial to this patient and could benefit from additional study in other athletes and athletic populations. Level of Evidence Level 5 [ABSTRACT FROM AUTHOR]

Background Muscular strength deficits are common after ACL injury. While the Limb Symmetry Index (LSI), using the uninvolved limb as a reference, is widely used, negative strength adaptations may affect both limbs post-injury. It is uncertain how the strength of the uninvolved limb in those with an ACL injury compares to uninjured individuals, making it unclear whether it is appropriate as a benchmark for determining sufficient strength. Purpose To compare the strength of key lower extremity muscles of the uninvolved limb in those with history of ACL injury (ACL-I) to the dominant limb in individuals with no history of ACL injury (control). Study Design Cross-sectional study. Methods: A total of 5,727 military cadets were examined, with 82 females and 126 males in the ACL-I group and 2,146 females and 3,373 males in the control group. Maximum isometric strength was assessed for six muscle groups measured with a hand-held dynamometer. Separate two-way ANOVAs with limb and sex were performed for each muscle group. Results Significant main effects for limb were observed with the uninvolved limb in the ACL-I group displaying greater strength compared to the dominant limb in the control group for the quadriceps, hamstrings, and gluteus medius, but effect sizes were small (Cohen's d <0.25). Significant main effects for sex were observed with greater male muscular strength in all six muscle groups with small to large effect sizes (Cohen's d 0.49-1.46). No limb-by-sex interactions were observed. Conclusions There was no evidence of reduced strength in the uninvolved limb in those with a history of ACL injury compared to the dominant limb in those with no prior ACL injury. This finding suggests that, after clearance to return to activities, the uninvolved limb can be used as a standard for comparison of sufficient strength, including when using the LSI. Level of Evidence: Level 3 [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a degenerative joint disease primarily affecting the elderly. It is characterized by the progressive decline of joint cartilage and alterations in the underlying bone. Several probiotic strains have exhibited immunomodulatory and anti‐inflammatory properties. Here, we examined the functions of live and dead Clostridium butyricum GKB7 (GKB7‐L and GKB7‐D) in a preclinical anterior cruciate ligament transection (ACLT)‐enhanced OA procedure. Oral administration of GKB7‐L and GKB7‐D ameliorated ACLT‐induced bone pain as assessed by weight‐bearing behavioral testing but did not affect body weight. Micro‐computed tomography (CT) results showed that GKB7‐L and GKB7‐D diminished ACLT‐induced bone destruction and loss. GKB7‐L and GKB7‐D‐enriched therapies also reduced ACLT‐induced production of the pro‐inflammatory cytokines interleukin (IL)‐1β and tumor necrosis factor (TNF)‐α, as well as the chondrolytic factor matrix metalloproteinase (MMP)‐3, leading to inhibition of aggrecan and collagen type II degradation and thereby blocking cartilage breakdown. We therefore suggest that oral supplementation with GKB7‐L or GKB7‐D can be beneficial in the prevention and treatment of OA. [ABSTRACT FROM AUTHOR]

Background: The development of less invasive all‐inside techniques regarding anterior cruciate ligament (ACL) reconstruction surgery has been associated with various advantages, including fewer complications and reduced postoperative pain. Silva et al. described a quadruple semitendinosus graft construct and suspensory button fixation for ACL reconstruction as an alternative technique. At the end of this technique, the tibial tunnel is filled with a bone autograft plug. This paper aims to examine the incorporation of the autograft and thus evaluate whether the "Silva technique" provides the same benefits as all‐inside techniques. Methods: A prospective study assessed 31 patients undergoing ACL reconstruction surgery using the "Silva technique." The cases involved in the study were skeletally mature patients with no previous history of ACL surgery or multiligamentous instability. All patients followed the same rehabilitation program and were examined at three standardized follow‐up visits: 4 months, 8 months, and 1 year postoperatively. Tegner–Lysholm knee score (TLKS), visual analog score (VAS) for pain, and the IKDC subjective knee score were completed at every visit. A knee MRI scan was performed at every scheduled visit to assess bone graft incorporation and remodeling. Results: TLKS scores revealed a considerable improvement compared to preoperative figures, from 57.2 points preoperatively to an average of 99.4 at the 12‐month follow‐up (p < 0.0001). VAS scores were substantially ameliorated after the operation and until the second follow‐up visit, from 5 before surgery to zero 8 months after the operation, with no noteworthy alterations afterward (p < 0.0001). IKDC subjective knee score outcomes were found to have increased at the last follow‐up, from 59.3 prior to surgery to 99.8 12 months postoperatively (p < 0.0001). Regarding the MRI features of the bone autograft, the tibial tunnel was entirely filled by bone formation at the last MRI scan, suggesting complete integration of the autograft in all patients. Conclusions: Bone autograft employed to seal the tibial tunnel was completely incorporated in all cases 1 year postoperatively. The "Silva technique" appears to feature all the avails of all‐inside techniques, whilst it seems to be simpler and easier than them after the surgeon is familiarized with its particular aspects. It is a robust option in orthopedic surgeons' arsenal. However, further large‐scale pertinent research is requisite to confirm the findings of this study. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the ultrastructural anatomy of the developing ACL tibial enthesis. We hypothesized that enthesis architecture would progressively mature and remodel, eventually resembling that of the adult by the early postnatal stage. Five fresh‐frozen human pediatric cadaveric knees aged 1–36 months underwent anatomical dissection to harvest the ACL insertion and underlying tibial chondroepiphysis. The samples were prepared for scanning electron microscopy (SEM) to examine the ultrastructural anatomy of the enthesis and underwent histological staining for circular polarized light (CPL) and light microscopy imaging. SEM analysis of the 1‐ and 8‐month‐old samples revealed a shallow interdigitation between the dense fibrous (ligamentous) tissue and unmineralized chondrogenic tissues, with a minimal transition zone. By 11‐month, a more complex transition zone was present. By age 19‐ and 36‐month‐old, a progressively more complex and defined fibrocartilage zone was observed. CPL analysis revealed distinct collagen fiber continuity, alignment, and organization changes over time. By 19 and 36 months, the samples exhibited complex fiber arrangements and a progression toward uniform fiber orientation. Similarly, histological analysis demonstrated progressive remodeling of the enthesis with increasing age. Our results suggest that the ACL enthesis of the developing knee begins to mimic that of an adult as early as 19 months of age, as a more complex transition between ligamentous and chondro‐epiphyseal tissue can be appreciated. We hypothesize that the observed changes are likely due to mechanical loading of the enthesis with the onset of weightbearing. Future investigations of ACL reconstruction and repair will benefit from improved understanding of the chondro‐epiphyseal/ACL regions. [ABSTRACT FROM AUTHOR]

Purpose Methods Results Conclusion Level of Evidence Posterior elongation of the physiological terminal sulcus (TS) due to lateral femoral condyle impaction fracture (LFC‐IF) after an anterior cruciate ligament (ACL) tear could potentially decrease the weight‐bearing area of the tibiofemoral joint, decrease the tension on lateral meniscus and cause flattening of the LFC which would influence rotational knee motion and cause anisometry of the lateral and anterolateral stabilizers. Therefore, the purpose of the study was to assess if the LFC‐IF elongates the physiological TS posteriorly.One hundred patients magnetic resonance images (MRIs) (75 males, 25 females, mean age 32.2 years, SD = 8.2) were included with a 1:1 ratio between the full‐thickness ACL tear group and the control group (patients with knee MRI performed due to other reasons, with no tear of ACL on MRI and negative clinical tests). Two independent raters evaluated the sagittal T1‐weighted preselected MRI scans. The principal measurement of interest was the distance from the intersection of the Blumensaat line with subchondral bone to the posterior border of the TS/LFC‐IF.The median distance from the Blumensaat line to the posterior border of the TS/LFC‐IF was significantly higher in the ACL tear group: 14.3 mm, interquartile range (IQR) = 11.6–16.4 mm versus control group: 12.8 mm, IQR = 9.0–15.0 mm, p = 0.038. Intrarater and inter‐rater reliabilities were >0.90.LFC‐IF after full‐thickness ACL tear significantly elongates the physiological TS in the posterior direction.Level III. [ABSTRACT FROM AUTHOR]

Chronic inflammation significantly contributes to the progression of osteoarthritis (OA), and an anti‐inflammatory small molecule derived from medicinal herbs could be a potential drug candidate for OA. Herein, we investigated the function and mechanism of Evodiamine (EAE), the active ingredient from Evodia rutaecarpa, in chondrocytes and macrophages in vitro and in vivo. The cytotoxicity of EAE was determined using an MTT assay. And the anti‐inflammatory and anti‐extracellular matrix (ECM) degradation effects of EAE were investigated using qRT‐PCR, western blot (WB), immunofluorescence (IF). Inductively Coupled Plasma Atomic Emission Spectrometry (ICP‐AES), Fluo‐4 AM, IF and AutoDock were used to elucidate the molecular mechanisms and signalling pathways of the reducing‐inflammatory properties of EAE on chondrocytes in vitro. Moreover, the effect of EAE on macrophage polarization was detected by IF and flow cytometry (FC). Ultimately, we explored the in vivo therapeutic efficacy of EAE in an anterior cruciate ligament transection (ACLT)‐induced OA model. The finding demonstrated that EAE blocked the phosphorylation of IKBα and Ca2+ influx, thereby curbing inflammation and ECM degradation. Additionally, EAE can prevent the polarization towards the M1 phenotype. Thus, our findings suggest that EAE has great potential as a therapeutic drug for the treatment of OA. [ABSTRACT FROM AUTHOR]

Background/Objectives: Anterior cruciate ligament (ACL) reconstruction (ACLR) is often followed by significant muscle atrophy and subsequent loss of strength. Blood flow restriction training (BFRT) has recently emerged as a potential mode of rehabilitation to mitigate these effects. The goal of this systematic review was to evaluate the efficacy of BFRT in functional recovery when compared to traditional rehabilitation methods. Methods: A literature review was conducted across July and August 2024 using multiple databases that reported randomised controlled trials comparing BFRT to traditional rehabilitation methods. Primary outcomes were changes to thigh muscle mass and knee extensor/flexor strength with secondary outcomes consisting of patient-reported functional measures (IKDC and Lysholm scores). The RoB-2 tool was used to assess the risk of bias. Results: Eight studies met the inclusion criteria; however, substantial heterogeneity prevented a meta-analysis being conducted for the primary outcomes. Three out of the five studies measuring muscle mass reported significant (p < 0.05) findings favouring BFRT. There was variation amongst the strength improvements, but BFRT was generally favoured over the control. Meta analysis of the secondary outcomes showed significant improvements (p < 0.05) favouring BFRT despite moderate heterogeneity. Conclusions: BFRT shows promise for maintaining muscle mass and improving patient reported outcomes following ACL reconstruction. However, the high risk of bias limits the strength of these conclusions. Further high-quality research needs to be conducted to establish optimal BFRT protocols for this cohort and to determine if BFRT has a place in ACL rehabilitation. [ABSTRACT FROM AUTHOR]

Background: This study aimed to evaluate the predictive value of anthropometric measurements for two-stranded peroneus longus tendon (PLT) graft thickness using ultrasonography Materials and methods: A prospective study was conducted on 204 healthy volunteers (102 males and 102 females) aged 18–40 years. Anthropometric measurements were recorded, including height, weight, body mass index (BMI), fibular length, calf circumference, and ankle circumference. The Tegner Activity Scale (TAS) was used to assess activity levels. PLT cross-sectional area (CSA) was measured using ultrasonography. Two-stranded PLT graft thickness was calculated using the previously reported formula by Luo et al. A thickness of less than 8 mm of PLT graft was accepted as an insufficient autograft for anterior cruciate ligament reconstruction (ACLR). Correlation and regression analyses were performed to identify predictors of two-stranded PLT graft thickness. Receiver operating characteristic (ROC) analysis was performed to establish the best threshold values. Results: Males had a significantly greater PLT CSA (0.17 ± 0.03 cm2) and predicted two-stranded PLT graft thickness (8.1 ± 0.6 mm) compared with females (0.15 ± 0.03 cm2 and 7.5 ± 0.6 mm, respectively; p < 0.001 for both). Correlation analysis revealed that two-stranded PLT graft thickness positively correlated with height, weight, BMI, fibular length, calf circumference, ankle circumference, and Tegner Activity Scale in both genders, with stronger correlations observed in females. The logistic regression model identified height and calf circumference as significant predictors of sufficient two-stranded PLT graft thickness (≥ 8 mm) in males, while calf circumference and the TAS were significant predictors in females. ROC analysis demonstrated that calf circumference and the TAS had acceptable discriminatory abilities in females, with 36.25 cm and ≥ 4 cutoff points, respectively. However, no anthropometric variables in males exhibited strong discriminatory abilities for predicting two-stranded PLT graft thickness Conclusions: Calf circumference and the TAS are significant predictors for two-stranded PLT autograft thickness in females. However, no anthropometric variables in males could be used strongly for prediction. These anthropometric measurements can assist in preoperative planning and decision-making, potentially improving ACLR outcomes by ensuring adequate graft thickness in females. Level of evidence: Level II prospective study [ABSTRACT FROM AUTHOR]

Non-contact anterior cruciate ligament injuries (NC-ACLs) represent a significant concern in sports medicine, particularly among athletes and physically active individuals. These injuries not only result in immediate functional impairment but also predispose individuals to long-term issues such as recurrent instability and early-onset osteoarthritis. This narrative review examines the biomechanical, neuromuscular, and environmental factors that contribute to the high incidence of NC-ACLs and evaluates the effectiveness of current prevention and rehabilitation strategies. The review identifies key risk factors, including improper landing mechanics, deficits in neuromuscular control, and muscle imbalances, which are pivotal in the etiology of NC-ACLs. Prevention programs that incorporate plyometric exercises, strength training, and neuromuscular education have shown efficacy in reducing injury rates. Rehabilitation protocols that emphasize a gradual return to sport, focusing on pain management, restoration of range of motion, and progressive strengthening, are critical for successful recovery and prevention of re-injury. The evidence suggests that an integrated approach, combining prevention and rehabilitation strategies tailored to the individual, is essential for minimizing NC-ACL risk and improving outcomes in affected populations. [ABSTRACT FROM AUTHOR]

Introduction: Osteoarthritis (OA) is a prevalent chronic degenerative disease, marked by a complex interplay of mechanical stress, inflammation, and metabolic imbalances. Recent studies have highlighted the potential of spermidine (SPD), a naturally occurring polyamine known for its antiinflammatory and antioxidant properties, as a promising therapeutic agent for OA. This study delves into the therapeutic efficacy and mechanistic pathways of SPD in mitigating OA symptoms. Methods: Forty Sprague-Dawley rats were randomly assigned to four groups, including the CG (sham operation), model (anterior cruciate ligament transection [ACLT], and treatment (ACLT + two different doses of SPD) groups. In vivo, correlations between OA severity and different interventions were assessed by ELISA, X-rays, CT imaging, histological staining, and immunohistochemistry. In vitro, IL-1β was used to trigger chondrocyte inflammation, and SPD's cytotoxicity was assessed in primary rat chondrocytes. Next, inflammatory markers, extracellular matrix (ECM) proteins, and pathway marker proteins were detected in chondrocytes administered IL-1β alone, SPD, or aryl hydrocarbon receptor (AhR) silencing, by qRT-PCR, Griess reaction, ELISA, Western blot, and immunofluorescence. Morphological alterations and pyroptosis in chondrocytes were examined by transmission electron microscopy (TEM) and flow cytometry. Results: Our research reveals that SPD exerts significant anti-inflammatory and antipyroptotic effects on IL-1β-treated chondrocytes and in anterior cruciate ligament transection (ACLT) rat models of OA, primarily through interaction with the Aryl hydrocarbon receptor (AhR). Specifically, SPD's binding to AhR plays a crucial role in modulating the inflammatory response and cellular pyroptosis by inhibiting both the AhR/NF-κB and NLRP3/caspase-1/GSDMD signaling pathways. Furthermore, the knockdown of AhR was found to negate the beneficial effects of SPD, underscoring the centrality of the AhR pathway in SPD's action mechanism. Additionally, SPD was observed to promote the preservation of cartilage integrity and suppress ECM degradation, further supporting its potential as an effective intervention for OA. Discussion: Collectively, our findings propose SPD as a novel therapeutic approach for OA treatment, targeting the AhR pathway to counteract the disease's progression and highlighting the need for further clinical evaluation to fully establish its therapeutic utility. [ABSTRACT FROM AUTHOR]

Background: Our study aims to examine stress–strain data of the four major knee ligaments—the anterior cruciate ligament (ACL), the posterior cruciate ligament (PCL), the medial collateral ligament (MCL), and the lateral collateral ligament (LCL)—under transient impacts in various knee joint regions and directions within the static standing position of the human body. Subsequently, we will analyze the varying biomechanical properties of knee ligaments under distinct loading conditions. Methods: A 3D simulation model of the human knee joint including bone, meniscus, articular cartilage, ligaments, and other tissues, was reconstructed from MRI images. A vertical load of 300 N was applied to the femur model's top surface to mimic the static standing position, and a 134 N load was applied to the impacted area of the knee joint. Nine scenarios were created to examine the effects of anterior, posterior, and lateral external forces on the upper, middle, and lower regions of the knee joint. Results: The PCL exhibited the highest stress levels among the four ligaments when anterior loads were applied to the upper, middle, and lower parts of the knee, with maximum stresses at the PCL-fibula junction measuring 59.895 MPa, 27.481 MPa, and 28.607 MPa, respectively. Highest stresses on the PCL were observed under posterior loads on the upper, middle, and lower knee areas, with peak stresses of 57.421 MPa, 38.147 MPa, and 26.904 MPa, focusing notably on the PCL-tibia junction. When a lateral load was placed on the upper knee joint, the ACL showed the highest stress 32.102 MPa. Likewise, in a lateral impact on the middle knee joint, the ACL also had the highest stress of 29.544 MPa, with peak force at the ACL-tibia junction each time. In a lateral impact on the lower knee area, the LCL had the highest stress of 22.279 MPa, with the highest force at the LCL-fibula junction. Furthermore, the maximum stress data table indicates that stresses in the ligaments are typically higher when the upper portion of the knee is affected compared to when the middle and lower parts are impacted. Conclusions: This study recommends people avoid impacting the upper knee and use the middle and lower parts of the knee effectively against external forces to minimize ligament damage and safeguard the knee. [ABSTRACT FROM AUTHOR]

Anterior cruciate ligament rupture is rare in children and adolescents, and unlike in adults, it occurs as an avulsion fracture at the tibial attachment rather than a mid-substance tear. Proximal avulsion fractures are extremely rare, and bone fragments may not be observed on radiographs in children, resulting in a delayed diagnosis. This paper reports a case of avulsion fracture of femoral attachment of anterior cruciate ligament with delayed diagnosis in a seven-year-old girl. [ABSTRACT FROM AUTHOR]

Anterior cruciate ligament (ACL) injury is a concerning problem in the paediatric population, impacting joint health and longevity. Moreover, ACL injury hampers physical activity, which is important for children's social network and general well‐being. Recent data demonstrates a rise in paediatric ACL reconstructions, affecting both girls and boys. However, it is unclear whether this rise reflects a higher injury rate or a more proactive approach towards surgery, as information on nonoperated patients is lacking. Regarding gender differences, increasing evidence implies that girls engaged in pivoting sports experience a higher incidence of ACL injuries and reinjuries compared to boys. Furthermore, data suggest that girls have inferior outcomes and lower return‐to‐sport rates than boys. The social context in which girls compete in sports is likely a significant contributing factor to the risk of serious knee injuries. Lack of attention and insufficient data on gender‐based differences in ACL injuries, outcomes and evidence‐based treatment guidelines highlight the need for further research on this topic. Level of Evidence: Level IV. [ABSTRACT FROM AUTHOR]

Background: The Knee Numeric-Entity Evaluation Score (KNEES-ACL) is a 41-item condition-specific patient-reported outcome measure (PROM) that was developed for patients with an anterior cruciate ligament (ACL) deficiency and patients after ACL reconstruction. This measure is intended to be used for longitudinal clinical studies. The KNEES-ACL has demonstrated face and content validity and superior responsiveness compared with other PROMs commonly used in patients with an ACL injury. However, this PROM was developed in Danish and has not been appropriately translated and culturally adapted into North American English. Purpose: To translate and culturally adapt the KNEES-ACL from Danish to North American English. Study Design: Cross-sectional study. Methods: Translation from Danish to English and cultural adaptation to a North American context were performed according to the dual panel method. First, the Danish KNEES-ACL was translated by a bilingual panel, which provided multiple English wording options for each item. Second, an English lay panel focus group was formed to determine the wording for each item that best reflected everyday spoken language. Finally, individual think-aloud cognitive interviews were conducted with patients after an ACL injury to evaluate the relevance, comprehensiveness, and comprehensibility of the PROM content and questions. Repeated modifications and testing were performed until a final English version of the KNEES-ACL was constructed. Results: Participants in the lay panel focus group were able to reach unanimous decisions for each of the 41 items. Further changes to 17 items were made after 8 think-aloud interviews with patients with ACL injuries at various time points to ensure that items were relevant and being interpreted consistently among different types of patients. The final KNEES-ACL consisted of 6 domains: Problems with Daily Activities, Mental Impact, Stability, Strength and Control, Pain, and Sport and Physical Activity. Conclusion: The English KNEES-ACL for patients with ACL injuries has undergone appropriate translation and cultural adaptation using established dual panel and cognitive interviewing methods in the population of interest. The psychometric properties of the English KNEES-ACL will likely mirror those established with the Danish version. However, direct validation of the psychometric properties of the English version would be beneficial before widespread use. [ABSTRACT FROM AUTHOR]

Background: There have been a large number of patient-reported outcome measures (PROMs) used to assess outcomes after anterior cruciate ligament (ACL) reconstruction (ACLR). Purpose/Hypothesis: The purpose was to determine which PROMs are being commonly used in randomized clinical trials (RCTs) to assess patients undergoing ACLR and to compare the responsiveness between them. It was hypothesized that the International Knee Documentation Committee (IKDC) score would be the most commonly used and responsive PROM among patients undergoing ACLR. Study Design: Meta-analysis. Level of evidence, 2. Methods: PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed, and relevant studies were extracted from the PubMed/MEDLINE and Web of Science databases. The inclusion criteria were English-language RCTs reporting on PROMs after ACLR. For articles meeting our inclusion criteria for responsiveness analysis (≥2 PROMs reported, 1 year minimum follow-up, and reported pre- and postoperative PROM means and standard deviations), the responsiveness between PROMs was compared using effect size (ES) and relative efficiency (RE). Results: A total of 108 articles met the inclusion criteria, comprising 9034 patients (mean age, 29.9 years; mean body mass index, 24.3; mean follow-up time, 36.1 months). There were 34 PROMs identified. The top 3 most commonly reported PROMs were the IKDC (n = 68; 63.0%), Lysholm (n = 65; 60.2%), and Tegner (n = 47; 43.5%) scores. The 2 PROMs with the highest ES were the ACL–Quality of Life (QoL) (3.37) and Knee Injury and Osteoarthritis Outcome Score (KOOS) QoL (2.07) scores. Compared with other PROMs, Lysholm and KOOS QoL scores had the greatest RE values. The Lysholm score had a greater RE than the KOOS Pain (RE, 1.17), KOOS Symptoms (RE, 1.22), KOOS Activities of Daily Living (ADL) (RE, 1.42), KOOS Sport/Recreation (RE, 1.55), KOOS QoL (RE, 1.41), and Tegner (RE, 2.89) scores. KOOS QoL had a greater RE than the IKDC (RE, 1.32), KOOS Pain (RE, 1.60), KOOS Symptoms (RE, 2.12), KOOS ADL (RE, 3.03), KOOS Sport/Recreation (RE, 1.27), and Tegner (RE, 2.06) scores. Conclusion: The IKDC score is the most commonly reported PROM in RCTs after ACLR; however, the Lysholm and KOOS QoL scores demonstrated the highest responsiveness in patients undergoing ACLR compared with other PROMs. [ABSTRACT FROM AUTHOR]

Objective: Over the past few years, histopathological studies have demonstrated that the ligamentum mucosum (LM) contains neural and vascular structures. These findings suggest that LM can be used for proprioception and revascularization in the repair of anterior cruciate ligament (ACL). The aim of this study was to evaluate the LM structure in knees with ACL injuries. Methods: The data of patients who underwent knee arthroscopy at our clinic between 2017 and 2022 were retrospectively analyzed. Three groups were included in the study; acute ACL tears (n=89), chronic ACL tears (n=111) and intact ACLs (n=101). The arthroscopic video records of all patients were evaluated retrospectively. LM was defined in three different forms: (1) Intact, (2) ruptured, and (3) non-presence. Results: The non-presence of the LM was significantly more common in chronic ACL tears compared to the other groups (p=0.021), while the presence of the LM (either intact or ruptured) was similar between acute ACL tears and intact ACLs. In acute tears, the number of intact LM was significantly lower than that of intact ACLs (p<0.001). However, it was significantly greater than that of chronic tears (p=0.001). Conclusion: According to the present study, the likelihood of intact LM in chronic ACL tears is quite low. In this regard, we suggest that performing surgery in the acute phase of ACL injury will increase the chances of using the LM as a neurovascular source. In addition, because of the possible effect of the LM on proprioception, we recommend preserving the structure during knee arthroscopy procedures if a healthy LM is present. [ABSTRACT FROM AUTHOR]

Objective: Cartilage and meniscus are important structures that maintain the health of the knee joint. Early detection of changes in the internal components of cartilage and meniscus before morphological changes occur is essential to prevent and delay the development of osteoarthritis (OA). This study was designed to determine the changes in the matrix composition of morphologically intact cartilage and meniscus during the acute phase of an anterior cruciate ligament (ACL) rupture, as well as the effect of different states of meniscus (intact or tear) on adjacent cartilage during the acute phase. Methods: This cross‐sectional study compared and analyzed 50 patients in the acute phase of ACL rupture who underwent surgical treatment and 66 age‐, weight‐ and height‐matched healthy volunteers from May 2022 to May 2023 at our institution. Mean T2 relaxation times and effect sizes in different regions of tibiofemoral articular cartilage and meniscus were compared between the two groups using the Mann–Whitney nonparametric t‐test, and correlations between different meniscal states and adjacent cartilage were analyzed. Results: Both in the lateral and medial compartments of the knee, T2 relaxation times were significantly higher in all subregions of cartilage and meniscus in the ACL rupture group (p < 0.05), and the site of injury was predominantly centered in the medial compartment (femur, p = 0.000; tibia, p = 0.000; anterior horn, p = 0.000). In the respective compartments, the posterior horn of the lateral meniscus showed a significant positive correlation with the mid‐cartilage of the femoral and tibial (r = 0.566, p = 0.035; r = 0.611, p = 0.02); and the posterior horn of the medial meniscus showed a significant positive correlation with the posterior tibial cartilage (r = 0.668, p = 0.018). Conclusion: During the acute phase of ACL rupture, the internal composition of the cartilage and meniscus undergoes significant changes, even if the morphology is intact. More importantly, the state of the meniscus significantly affects the internal composition of the adjacent cartilage. This is an early warning sign of OA, which should be closely monitored and carefully managed in clinical practice. [ABSTRACT FROM AUTHOR]

Women's football has grown in popularity, competitiveness and professionalism, increasing the demands placed on players and their injury risk. This study aimed to identify differences in the match workload and international travel between injured and non‐injured professional women's footballers. The study was conducted as an observational, retrospective, case‐control study over two football seasons (2021/2022 and 2022/2023) in four top‐tier European women's football leagues. Fifty‐eight professional women football players (81 injuries) formed the injury group and were matched with 81 elite women football players (162 non‐injuries), from the same league, to form the control group. For each injury, cumulative match workload (minutes played, appearances, days between matches, rest) and international travel (distances, time, time zones crossed) were calculated over a 28‐day period preceding the injury, for both the injured players and matched controls. The injured group had a higher number of instances of less than 5 days between matches compared to the controls (p = 0.03, effect size = 0.3, small). The anterior cruciate ligament injury group made more appearances (p = 0.09, effect size = 0.8, moderate), had more instances of less than 5 days between matches (p = 0.09, effect size = 0.8, moderate) and had less rest time (p = 0.12, effect size = 0.8, moderate) than the control group. No meaningful differences were observed between the hamstring injury group and the control group. These findings underscore the importance of careful consideration when developing match fixture schedules in elite women's football, particularly concerning the number of matches scheduled in a short period. Strategies to increase rest and recovery are recommended to safeguard players against injuries. Highlights: Instances of less than 5 days between matches in elite women's football were significantly higher in the injured group compared to the non‐injured group.Elite female footballers who sustained anterior cruciate ligament (ACL) injuries made more appearances, had more instances of less than 5 days between matches and had less rest time in the 28 days prior to the injury than the non‐injured players.Elite female footballers who sustained ACL injuries also travelled further, for longer and crossed more time zones than the non‐injured players. [ABSTRACT FROM AUTHOR]

Research of non-contact anterior cruciate ligament (ACL) injury risk aims to identify modifiable risk factors that are linked to the mechanisms of injury. Information from these studies is then used in the development of injury prevention programmes. However, ACL injury risk research often leans towards methods with three limitations: 1) a poor preservation of the athlete-environment relationship that limits the generalisability of results, 2) the use of a strictly biomechanical approach to injury causation that is incomplete for the description of injury mechanisms, 3) and a reductionist analysis that neglects profound information regarding human movement. This current opinion proposes three principles from an ecological dynamics perspective that address these limitations. First, it is argued that, to improve the generalisability of findings, research requires a well-preserved athlete-environment relationship. Second, the merit of including behaviour and the playing situation in the model of injury causation is presented. Third, this paper advocates that research benefits from conducting non-reductionist analysis (i.e., more holistic) that provides profound information regarding human movement. Together, these principles facilitate an ecological dynamics approach to injury risk research that helps to expand our understanding of injury mechanisms and thus contributes to the development of preventative measures. [ABSTRACT FROM AUTHOR]

This paper explores the use of biomechanics in identifying the mechanistic causes of musculoskeletal tissue injury and degeneration. It appraises how biomechanics has been used to develop training programmes aiming to maintain or recover tissue health. Tissue health depends on the functional mechanical environment experienced by tissues during daily and rehabilitation activities. These environments are the result of the interactions between tissue motion, loading, biology, and morphology. Maintaining health of and/or repairing musculoskeletal tissues requires targeting the "ideal" in vivo tissue mechanics (i.e., loading and deformation), which may be enabled by appropriate real-time biofeedback. Recent research shows that biofeedback technologies may increase their quality and effectiveness by integrating a personalised neuromusculoskeletal modelling driven by real-time motion capture and medical imaging. Model personalisation is crucial in obtaining physically and physiologically valid predictions of tissue biomechanics. Model real-time execution is crucial and achieved by code optimisation and artificial intelligence methods. Furthermore, recent work has also shown that laboratory-based motion capture biomechanical measurements and modelling can be performed outside the laboratory with wearable sensors and artificial intelligence. The next stage is to combine these technologies into well-designed easy to use products to guide training to maintain or recover tissue health in the real-world. [ABSTRACT FROM AUTHOR]

Purpose: To compare the anterior and posterior trans-septal (TS) portal approaches in anterior cruciate ligament reconstruction (ACLR) by evaluating femoral tunnel positioning and passive anterior tibial subluxation (PATS). Methods: A total of 205 patients who underwent primary ACLR using the outside-in technique between March 2018 and December 2021 were retrospectively enrolled. Patients were classified into two groups based on the viewing techniques: the anterior group was treated using anteromedial or anterolateral portals (n = 155), and the TS group was treated using posterior TS portal (n = 55). The relative locations of the femoral tunnel were evaluated using the deep-shallow planes (X-axis) and superior-inferior planes (Y-axis) with the quadrant method in the lateral femoral condyle on a 3-dimensional computed tomography image. Anterior tibial subluxation for the lateral and medial compartments relative to the femoral condyles was evaluated as measured on magnetic resonance imaging. Knee laxity was assessed using the pivot-shift test and stress radiography. Results: In the posterior TS group, the femoral tunnel was usually located deeper on the X-axis and more superior on the Y-axis, which corresponds to a more proximal position, than in the anterior group (deeper on the X-axis and superior on the Y-axis). Moreover, the femoral tunnel locations in this group were more compactly distributed than those in the anterior group. The TS group showed significantly better reduction of postoperative PATS in the lateral compartments than the anterior group (anterior group vs. TS group: lateral compartment, 3.2 ± 3.1 vs. 4.5 ± 3.2 mm; p =.016). Significantly better results were found in the TS group for knee stability as assessed by the pivot-shift grade (p =.044); however, there were no significant differences between the two groups with respect to patient-reported outcome measures (p >.05) and other complications (p =.090). Conclusion: Our results suggest that positioning the femoral tunnel using the posterior TS portal approach may lead to better outcomes in terms of PATS and rotational stability compared to the anterior portal approach in ACLR. [ABSTRACT FROM AUTHOR]

Background and Objectives: Remodeling and healing of the graft are crucial processes for long-term graft survival after anterior cruciate ligament reconstruction (ACLR). However, few studies have objectively evaluated the differences in graft healing between autografts and allografts. This study aimed to compare the status of the anterior cruciate ligament (ACL) grafts between hamstring tendon (HT) autografts and tibialis anterior tendon (TAT) allografts using second-look arthroscopy. Materials and Methods: The outcomes of 193 consecutive patients (153 males and 40 females, with an average age of 30.38 and BMI of 25.43 kg/m2) who underwent second-look arthroscopy following primary ACLR were retrospectively reviewed. Prior to participating in this study, all patients provided written informed consent. The patients were divided into two groups: those with HT autografts and those with TAT allografts. Confounding factors were matched between the two groups using propensity score matching (PSM). ACL graft status was assessed during second-look arthroscopy using a numeric scale system based on the degree of four parameters: graft tension, continuity, synovium coverage, and vascular marking. Clinical outcomes were assessed using the Lysholm and International Knee Documentation Committee (IKDC) scores. Graft status and clinical outcomes were compared between the two groups. Additionally, a subgroup analysis based on the timing of the second-look arthroscopy (12–24 months vs. >24 months after the initial ACLR) was conducted. Results: After PSM, 62 patients were included in each group. The second-look arthroscopy was conducted at 23.6 ± 6.6 months for the HT group and at 24.0 ± 7.9 months for the TAT group (p = 0.749). The continuity and tension of the ACL graft were not significantly different between the two groups (p = 0.146 and 0.075, respectively). However, the TAT group exhibited significantly inferior synovial coverage and vascular marking of the ACL graft compared with the HT group (p = 0.021 and 0.007, respectively). These findings were consistent regardless of the timing of the second-look arthroscopy. Clinical outcomes, according to the Lysholm and IKDC scores, significantly improved in both groups with no significant differences (p = 0.386 and 0.733, respectively). Conclusions: Although there were no differences in graft tension and continuity between HT autografts and TAT allografts, the biological healing of ACL grafts, in terms of synovialization and vascularization, was superior in HT autografts compared to TAT allografts. [ABSTRACT FROM AUTHOR]

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To confirm the protective mechanism of genistein on osteoarthritis (OA). Firstly, we constructed an anterior cruciate ligament transection (ACLT) rat model and administered two doses of genistein via gavage. The effects of the drug on cartilage damage repair and synovitis in OA rats were evaluated through pain-related behavioral assessments, pathological staining, detection of inflammatory factors, and western blot analysis. Secondly, we constructed IL-1-induced chondrocytes and synovial fibroblast models, co-incubated them with genistein, and evaluated the protective effects of genistein on both types of cells through cell apoptosis and cytoskeleton staining. To verify the role of this pathway, we applied the GSK3β inhibitor TWS119 and the Wnt/β-catenin inhibitor XAV939 to ACLT rats and two types of cells to analyze the potential mechanism of genistein's action on OA. Our results confirmed the protective effect of genistein on joint cartilage injury in ACLT rats and its alleviating effect on synovitis. The results of cell experiments showed that genistein can protect IL-1β-induced chondrocytes and synovial fibroblasts, inhibit IL-1β-induced cell apoptosis, increase the fluorescence intensity of F-actin, and inhibit inflammatory response. The results of in vivo and in vitro mechanism studies indicated that TWS119 and XAV939 can attenuate the protective effects of genistein on OA rats and IL-1-induced cell damage. Our research confirmed that genistein may be an effective drug for treating osteoarthritis. Furthermore, we discussed and confirmed that the GSK3β/Wnt/β-catenin axis serves as a downstream signaling pathway of genistein, providing theoretical support for its application. [ABSTRACT FROM AUTHOR]

Failure rates among primary Anterior cruciate ligament reconstruction range from 3.2 to 11.1 %. Recently, there has been increased focus on surgical and anatomic considerations which predispose patients to failure, including excessive posterior tibial slope (PTS), unaddressed high-grade pivot shift, and improper tunnel placement. The purpose of this review was to provide a current summary and analysis of the literature regarding patient-related and technical factors surrounding revision ACLR, rehabilitation considerations, overall outcomes, and return to sport (RTS) for patients who undergo revision ACLR. In revision ACLR patients, those receiving autografts are 2.78 times less likely to experience a re-rupture compared to patients who receive allografts. Additionally, individuals with properly positioned tunnels and removable implants are considered strong candidates for one-stage revision procedures. Conversely, cases involving primary tunnel widening of approximately 15 mm are typically indicative of two-stage revision ACLR. These findings underscore the importance of graft selection and surgical approach in optimizing outcomes for patients undergoing revision ACLR. Given the high rates of revision surgery in young, active patients who return to pivoting sports, the literature recommends strong consideration of a combined ACLR + anterolateral ligament (ALL) or lateral extra-articular tenodesis (LET) procedure in this population. Unrecognized posterolateral corner (PLC) injury is a common cause of ACLR failure and current literature suggests concurrent operative management of high-grade PLC injuries. Excessive PTS has been identified as an independent risk factor for ACL graft failure. Consider revision ACLR with combined slope-reducing tibial osteotomy in cases of posterior tibial slope greater than 12°. [ABSTRACT FROM AUTHOR]

Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose Methods Results Conclusions Level of Evidence A lack of standardization exists for functional tasks in return‐to‐activity (RTA) guidelines for adolescents with anterior cruciate ligament injury (ACLi). Identifying the variables that discern ACLi status among adolescents is a first step in the creation of such guidelines following surgical reconstruction. This study investigated the use of classification models to discern ACLi status of adolescents with and without injury using spatiotemporal variables from functional tasks typically used in RTA guidelines for adults.Sixty‐four adolescents with ACLi and 70 uninjured adolescents completed single‐limb hops, lunges, squats, countermovement jumps and drop‐vertical jumps. Jumping distances, heights, and depths were collected. Decision trees (DTs) were used to classify ACLi status and were evaluated using the F‐measure (F1), kappa statistic (ĸ) and area under the precision–recall curve (PRC). Independent t tests and effect sizes were calculated for each important classifier of the DT models.A five‐variable model classified ACLi status with an accuracy of 67.5% (F1 = 0.6842; ĸ = 0.350; PRC = 0.491) with sex as a classifier. Significant differences were found in three of the four spatiotemporal variables (p ≤ 0.002). Separate models then classified ACLi status in males and females with an accuracy of 53.3% (F1 = 0.5882; ĸ = 0.0541; PRC = 0.476) and 76.9% (F1 = 0.7692; ĸ = 0.541; PRC = 0.528), respectively, with significant differences for all variables (p ≤ 0.013).Among the DT models, females were better able to classify ACLi status compared to males, highlighting the importance of sex‐specific rehabilitation guidelines for adolescents.Level III. [ABSTRACT FROM AUTHOR]

Purpose Methods Results Conclusion Level of Evidence Similar to the anterior cruciate ligament, the femoral footprint of the posterior cruciate ligament (PCL) is composed of different fibre areas, possibly having distinct biomechanical functions. The aim of this study was to determine the role of different fibre areas of the femoral footprint of the PCL in restraining posterior tibial translation (PTT).A sequential cutting study was performed on eight fresh‐frozen human knee specimens, utilizing a six‐degrees‐of‐freedom robotic test setup. The femoral attachment of the PCL was divided into 15 areas, which were sequentially cut from the bone in a randomized sequence. After determining the native knee kinematics, a displacement‐controlled protocol was performed replaying the native motion, while constantly measuring the force. The reduction of the restraining force presented the percentage contribution of each cut, according to the principle of superposition.The PCL was found to contribute 29 ± 16% in 0°, 51 ± 24% in 30°, 60 ± 22% in 60° and 55 ± 18% in 90°, to restricting a PTT. The fibre areas contributing the most were located at the proximal border of the PCL footprint, away from the cartilage, and directly adjacent to the medial intercondylar ridge (p < 0.05). Of these, one fibre area showed the highest contribution at all flexion angles. This area was located at the posterior half of the medial intercondylar ridge. No clear assignment of the areas to either the anterolateral or posteromedial bundle was possible.An area towards the proximal and posterior part of the femoral PCL footprint was found to significantly restrain a posterior tibial force. Based on the data of this testing setup, a PCL graft positioned at the identified area may best mimic the part of the native PCL, which bears the most load in resisting a PTT force.No evidence level (laboratory study). [ABSTRACT FROM AUTHOR]

BACKGROUND: Anterior cruciate ligament rupture is one of the injuries that seriously affect life and sports performance, and the anterior cruciate ligament as a stabilizing structure is irreplaceable in maintaining sports performance. In view of its severe injury manifestations, the current treatment for anterior cruciate ligament rupture is a surgery for anterior cruciate ligament reconstruction. Since an anterior cruciate ligament injury can cause loss of mechanoreceptors, which in turn causes a reduction in proprioception, it is a great problem for patients to recover their motor performance. OBJECTIVE: To summarize the effects of proprioceptive training on clinical outcomes after anterior cruciate ligament reconstruction and to explore the underlying mechanisms, thereby providing more references for clinical prevention and treatment. METHODS: A computerized search of PubMed, CNKI, WanFang Data, and VIP databases was conducted for literature (from January 2013 to March 2023) related to proprioceptive training after anterior cruciate ligament reconstruction that improves joint stability and motor balance ability. A total of 108 articles were finally included for review. RESULTS AND CONCLUSION: Proprioceptive training can effectively improve the proprioceptive functions of patients, such as positional sense and kinesthetic sense after anterior cruciate ligament reconstruction, and improve joint stability, postural control and motor ability. The proprioceptive training improves the proprioceptive function through three mechanisms: stimulation of periprosthetic receptors around the knee joint, activation of spinal reflex stimulation, reinforcement of motor control in the brain, and enhancement of cognitive processing. The proprioceptive training may improve proprioceptive functions by activating the potential mechanisms of growth associated protein-43 activity, Piezo2 mechanotransducer, and NT-3/TrkC signaling pathway. Hydrotherapy is the mainstay in the early stages, while neuromuscular training, individual strength training and visual feedback training are prioritized in the middle and late stages. There exists an as-yet-unsegmented reconstructive surgery graft, sex, and a lack of devices or proprioceptive training methods based on the idea of combining multiple sensory stimuli. [ABSTRACT FROM AUTHOR]

Background: The positioning error of femoral tunnel was the key factor leading to the failure of anterior cruciate ligament (ACL) reconstruction. This study aimed to propose a new femoral tunnel classification to guide revision ACL reconstruction. Methods: Totals of 150 patients with ACL reconstruction failure from 2017 to 2023 were enrolled in this retrospective study. According to the tunnel diameter, shape, posterior wall and the positioning relationship with the Lateral Intercondylar Ridge on the three-dimensional CT imaging, we divided the femoral tunnels into four types: Type I off-target type, Type II straddled type, Type III anatomical type, and Type IV irregular type. Finally, explored the inter-observer reliability within two groups of doctors (Group A, 12 high seniorities; Group B, 12 low seniorities), and evaluated the intra-observer reliability within 6 doctors after two months. Clinical evaluation was performed using the Lysholm score, Tenger activity score, Pivot Shift and anterior knee laxity measurements. Results: Among 150 cases of femoral tunnel three-dimensional CT reconstructed imaging, 144 cases were successfully included in the classification system, and 6 cases were confirmed as uncertain type. We measured the Kappa (κ) coefficient of group A was significantly higher than that of group B (κ 0.72 VS 0.68), and the κ coefficient of group A was still higher than group B (κ 0.69 VS 0.62) after further dividing Type III anatomical type into three subtypes. In addition, the κ coefficients of intra-observer reliability were all exceeded 0.73. Clinical follow-up showed that 9 patients had good knee joint motor function and stability after operation. Conclusion: The new femoral tunnel classification was reliable and had clinical guiding significance based on three-dimensional CT imaging. Level of evidence: Level III. [ABSTRACT FROM AUTHOR]

Objectives Methods Results Conclusions The type of ligamentous tear and the degree of knee laxity have important guiding significance for the diagnosis and management of anterior cruciate ligament (ACL) tears. Instrumental measurement is necessary for ACL tears since physical examination and magnetic resonance imaging (MRI) cannot provide an objective and quantitative assessment of knee laxity. This study aimed to compare the application of a novel knee arthrometer and simultaneous stress radiography in differentiating between complete and partial acute ACL tears, and further assess the correlation between the two measurements.A total of 106 patients with complete acute ACL tears and 52 patients with partial acute ACL tears were included in the study. Preoperative arthrometry and simultaneous stress radiography were performed using the Ligs arthrometer at 90, 120, and 150 N to assess side‐to‐side difference (SSD) in anterior knee laxity. The optimal threshold was determined using the receiver operating characteristic (ROC) curve. The area under the ROC curve (AUC) was used to assess the diagnostic value of the measurement. Pearson's correlation coefficient was used to assess the correlation between the two measurements.The optimal differential SSD thresholds in the Ligs arthrometer were 2.7 mm at 90 N, 3.8 mm at 120 N, and 4.6 mm at 150 N. Similarly, the optimal differential SSD thresholds in simultaneous stress radiography were 3.8 mm at 90 N, 5.1 mm at 120 N, and 5.6 mm at 150 N. The AUC analysis revealed that the Ligs arthrometer was fairly informative at 90 N (AUC = 0.851), 120 N (AUC = 0.878), and 150 N (AUC = 0.884), and simultaneous stress radiography was highly informative at 90 N (AUC = 0.910), 120 N (AUC = 0.925), and 150 N (AUC = 0.948). Moreover, the AUC of the combined measurements was 0.914 at 90 N, 0.931 at 120 N, and 0.951 at 150 N. A significantly strong correlation was found between the two measurements at 90 N (r = 0.743, p < 0.001), 120 N (r = 0.802, p < 0.001), and 150 N (r = 0.823, p < 0.001).The Ligs arthrometer and simultaneous stress radiography proved to be valid diagnostic tools to differentiate between complete and partial acute ACL tears, with a strong correlation between the two measurements in SSD values. Compared with single instrumental measurement, the combination of the two measurements can further improve the diagnostic value in this regard. [ABSTRACT FROM AUTHOR]

Background: Anterior cruciate ligament reconstruction (ACLR) using double adjustable fixation gained popularity in the last decade due to its minimally invasive technique. However, suspensory fixation devices could be related to recurrent instability, poor clinical outcomes, and patient dissatisfaction. The present study aims to evaluate the clinical outcomes following ACLR using double adjustable-loop suspensory fixation devices in the demanding population of young patients. Methods: Between 2019 and 2022, 95 patients with knee post-traumatic anterior cruciate ligament insufficiency were treated with primary ACLR using semitendinosus quadrupled graft and double adjustable-loop suspensory fixation devices and followed for at least two years. Concomitant lesions were also treated at the same surgical time. The knee examination form of the International Knee Documentation Committee (IKDC) was used to assess clinical evaluation, and the return to physical activities using the Tegner Activity Scale was recorded. Patient-reported objective measures (PROMs) were also evaluated, including the IKDC subjective and Lysholm scores. Results: Sixty-six males and twenty-nine females with a mean age of 23.8 (range 18–37) and a mean BMI of 24.9 (SD ± 2.42) kg/m2 were included in this study. All patients were evaluated clinically as normal or nearly normal at the final follow-up. PROMs also significantly improved postoperatively (p < 0.05) compared to the preoperative values. The Tegner Activity Scale increased from 2 to 7, the IKDC mean score improved from 43.9 (±8.9) to 93.3 (±12.3), and the modified Lysholm from 47.3 (±11.1) to 92.9 (±16.6). No complications or adverse events were recorded. Conclusions: Anterior cruciate ligament reconstruction utilizing double adjustable-loop suspensory fixation devices provides good clinical and functional outcomes in young patients at a two-year follow-up. [ABSTRACT FROM AUTHOR]

Simple Summary: Cranial cruciate ligament (CCL) disease often involves damage to the caudal horn of the medial meniscus, resulting in pain and the progression of osteoarthritis. Current treatments, primarily partial caudal meniscectomy, have shown disappointing long-term outcomes as osteoarthritis progresses. Consequently, restoring and preserving meniscal tissue is becoming increasingly important for maintaining the integrity and functionality of the meniscus whenever possible. Although meniscal suture techniques have been documented in canine cases, their clinical application remains limited. This study aims to assess the practicability of a minimally invasive double-needle technique (DNT) designed to facilitate meniscal sutures during arthroscopy with the use of joint distraction. The technique was applied in ten canine stifles undergoing arthroscopy for CCL disease with confirmed medial meniscal lesions of the caudal horn appropriate for suturing. The described DNT proved to be a viable method for suturing the caudal horn of the medial meniscus. It can be effectively applied in canine stifles, provided there is adequate visualization during the procedure. Current treatments for medial meniscus lesions in association with CCL ruptures have shown disappointing long-term outcomes. Meniscal suturing may improve the outcome, but their clinical application remains limited. This study aims to assess the practicability of a minimally invasive DNT to facilitate meniscal suturing in dogs. Ten stifles of eight client-owned dogs with arthroscopically confirmed CCL disease and medial meniscal tears in the abaxial third of the meniscus were included. The described suture technique was applied under joint distraction using the Titan joint distractor. Surgical stabilization of all stifles was then accomplished via an X-Porous TTA procedure. The DNT allowed for the precise placement of meniscal sutures. Minor intraoperative complications included reduced arthroscopic visibility (n = 2) and suture breakage during its passage through the meniscus (n = 3). No complications related to the meniscal sutures were noted throughout the six-month follow-up period. The described DNT proved to be a viable and effective method for suturing lesions of the caudal horn of the medial meniscus, provided there is adequate visualization during the procedure. Appropriate stifle stabilization postoperatively is mandatory for protecting the suture and avoiding concomitant meniscal lesions due to joint instability. [ABSTRACT FROM AUTHOR]

Introduction: Accurate assessment of anterior cruciate ligament (ACL) function is vital for guiding treatment. Nevertheless, the presence of tibial subluxation in the neutral position of a patient with an ACL injury may potentially introduce a confounding factor. This study aims to investigate whether tibial subluxation in the neutral position affects the diagnosis of anterior instability in patients with ACL injuries, potentially impacting the reliability and diagnostic accuracy of stress radiography. Methods: This study included 88 patients: 30 with acute complete ACL tears (acute group), 28 with chronic complete ACL tears (chronic group), and 30 patients who underwent knee arthroscopic surgery other than ACL reconstruction (control group). Side-to-side differences (SSD) in stress radiography were measured using the Telos load status and the SSD of the gap between the Telos load and unload statuses. Diagnostic accuracy of the two methods was assessed using areas under the receiver operating characteristic curves (AUCs). Results: The load SSD (5.92 ± 5.28 mm) was higher than the load-unload SSD (4.27 ± 5.99 mm) in the chronic group (P = 0.017). The load SSD demonstrated a significantly higher diagnostic value than that of the load-unload SSD in the combined group (AUC = 0.920 vs. 0.830; P = 0.012) and chronic group (AUC = 0.913 vs. 0.754; P = 0.002). After adjusting the symptoms for radiographic duration from 6 to 3 months in the chronic group, the load SSD exhibited a significantly higher diagnostic value (AUC = 0.902) than that of the load-unload SSD (AUC = 0.740; P < 0.001). Conclusion: The load SSD provides superior diagnostic accuracy compared to the load-unload SSD in ACL tear cases, where static anterior tibial subluxation may result in false negatives. Although load-unload SSD may have diagnostic value within the first 3 months post-injury, the load SSD method provides a reliable assessment of ACL function for patients beyond this timeframe. [ABSTRACT FROM AUTHOR]

Background: The desire to return to sports (RTS) and return to performance at preinjury level (RTSP) is a common motivator for athletes undergoing anterior cruciate ligament (ACL) reconstructive surgery. However, for non-elite athletes little is known about the patient and surgical variables influencing RTS/RTSP. Purpose was to determine which patient or surgical variables had an effect on RTS/RTSP in non-elite athletes. We also analyzed whether patients that RTS and RTSP have more confidence in the knee and less difficulty pivoting. Methods: A single-centre retrospective cohort study. All patients who had undergone primary hamstring ACL reconstruction within a 5-year period were included. Patients were asked about their pre- and postoperative sports participation using the Tegner Activity Score (TAS) as well as about their RTS/RTSP. Confidence in the knee and difficulty with pivoting were asked about. To determine the potential adverse effect of patient variables at the time of surgery (sex, age, height, weight, TAS preop) and surgical variables (graft diameter, surgical technique, concomitant injury) influencing RTS/RTSP, univariate and multivariate logistic regression analysis were used. Results: 370 ACL reconstructions were included. Average follow-up was 4.6 years (SD 1.4). RTS rate was 65% and RTSP 43%. Median preinjury TAS was 7 (Q1:6, Q3:8)), postoperative 6 (Q1:4, Q3:7). Multivariate analysis showed that women were more likely to RTS (OR 2.40, 1.16–4.97). A lower preinjury TAS (OR 0.80, 0.67–0.95) resulted in higher RTSP levels. None of the surgical variables had a significant influence on RTS or RTSP. Patients who returned to sports or to preinjury-level performance displayed significantly more confidence in the operated knee and less difficulty pivoting than non-returning patients. Conclusion: Our study shows that 65% of non-elite athletes with an ACL reconstruction returned to sports, 43% at preinjury level. Women were over twice more likely to RTS than men. Preinjury TAS significantly influences RTSP, with a lower preinjury TAS leading to a higher percentage of RTSP. Patients returning to both scored better in their self-reported confidence in the knee and difficulty pivoting than non-returning patients. Level of evidence: Retrospective cohort III. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to determine if patients with chronic ankle instability (CAI) exhibit biomechanical changes associated with the increased risk of anterior cruciate ligament (ACL) injury during landing tasks. Study Design: This study was conducted through systematic review and meta-analysis. Data Sources: Searches were conducted in May 2024 across five electronic databases, including Web of Science, Scopus, PubMed, SPORTDiscus, and Cochrane Library. Eligibility Criteria: Studies were included if they (1) involved subjects with CAI and healthy controls and (2) assessed biomechanical variables such as ground reaction forces, joint angles, and joint torques. Results: Of the 675 identified studies, 171 were included in the review, and 13 were eligible for meta-analysis. The reviewed studies clearly defined research objectives, study populations, consistent participant recruitment, and exposures, and they used valid and reliable measures for outcomes. However, areas such as sample size calculation, study sample justification, blinding in assessments, and addressing confounders were not robust. This meta-analysis involved 542 participants (healthy group: n = 251; CAI group: n = 291). Compared with healthy individuals, patients with CAI exhibited a greater peak vertical ground reaction force (peak VGRF; SMD = 0.30, 95% CI: 0.07-0.53, p = 0.009), reduced hip flexion angles (SMD = -0.30, 95% CI: -0.51 to -0.17, p < 0.0001), increased trunk lateral flexion (SMD = 0.47, 95% CI: 0.05 to 0.9, p = 0.03), greater hip extension moments (SMD = 0.47, 95% CI: 0.09-0.84, p = 0.02), and increased knee extension moments (SMD = 0.39, 95% CI: 0.02-0.77, p = 0.04). Conclusion: During landing tasks, patients with CAI demonstrate increased hip extension moments and knee extension moments, decreased hip flexion angles, increased peak VGRF, and increased trunk lateral flexion angles. These biomechanical variables are associated with an elevated risk of ACL injuries. [ABSTRACT FROM AUTHOR]

Background: Facilitating the healing process of injured anterior cruciate ligament (ACL) tissue is crucial for patients to safely return to sports. Stem cell derived exosomes have shown positive effects on enhancing the regeneration of injured tendons/ligaments. However, clinical application of exosomes in terms of storage and pre-assembly is challenging. We hypothesized that lyophilized exosomes derived from human umbilical cord stem cells (hUSC-EX) could enhance the cell activity of chronically injured ACL cells. Materials and methods: We harvested the 8 weeks injured ACL cells from rabbit under IACUC (No. 110232) approval. The studied exosomes were purified from the culture medium of human umbilical cord stem cells (IRB approval No. A202205014), lyophilized to store, and hydrated for use. We compared exosome treated cells with non-exosome treated cells (control group) from the same rabbits. We examined the cell viability, proliferation, migration capability and gene expression of type I and III collagen, TGFβ, VEGF, and tenogenesis in the 8 weeks injured ACL cells after hUSC-EX treatment. Results: After hydration, the average size of hUSC-EX was 84.5 ± 70.6 nm, and the cells tested positive for the Alix, TSG101, CD9, CD63, and CD81 proteins but negative for the α-Tubulin protein. After 24 h of treatment, hUSC-EX significantly improved the cell viability, proliferation and migration capability of 8 weeks injured ACL cells compared to that of no exosome treatment group. In addition, the expression of collagen synthesis, TGFβ, VEGF, and tenogenesis gene were all significantly increased in the 8 weeks injured ACL cells after 24 h hUSC-EX delivery. Discussion: Lyophilized exosomes are easily stored and readily usable after hydration, thereby preserving their characteristic properties. Treatment with lyophilized hUSC-EX improved the activity and gene expression of 8 weeks injured ACL cells. Conclusion: Lyophilized hUSC-EX preserve the characteristics of exosomes and can improve chronically injured (8 weeks) ACL cells. Lyophilized hUSC-EX could serve as effective and safe biomaterials that are ready to use at room temperature to enhance cell activity in patients with partial ACL tears and after remnant preservation ACL reconstruction. [ABSTRACT FROM AUTHOR]

The anterior cruciate ligament (ACL) is crucial for knee stability and is often injured in sports, leading to significant issues like degenerative changes and meniscal tears. ACL tears are prevalent in high-school sports injuries, accounting for 50% of knee injuries in the U.S. Surgical reconstruction, often involving bone-patellar tendon-bone (BPTB) or hamstring autografts, is common, with varying success rates and complications. Emerging alternatives like the peroneus longus tendon show promise but require further comparative studies. This prospective and multicentric study included 110 patients who underwent ACL reconstruction from 2020 to 2022. Fifty-five patients received hamstring tendon autografts (Group H) and fifty-five received peroneus longus tendon autografts (Group P). Surgeries were performed by experienced surgeons using standardized techniques. Patients were evaluated using clinical tests and functional scores including the Lysholm Knee Questionnaire and IKDC-2000 at various postoperative intervals up to 24 months. Data were analyzed using SPSS with a significance level set at p < 0.05. Group H showed superior knee function preoperatively and at 24 months postoperatively compared to Group P. Group H had higher Lysholm and IKDC scores consistently throughout the study period. The anterior drawer and Lachman's tests indicated better knee stability for Group H. Complications were comparable between groups, with specific issues related to donor site morbidity and muscle weakness observed in each. The six-strand hamstring tendon autograft (Group H) demonstrated superior functional outcomes and knee stability compared to the peroneus longus tendon autograft (Group P) for ACL reconstruction. Despite some donor site morbidity, the hamstring tendon showed better long-term recovery and fewer complications. Future studies should explore larger, multicentric cohorts and integrate regenerative medicine techniques to further enhance ACL reconstruction outcomes. [ABSTRACT FROM AUTHOR]

Background: Anterior cruciate ligament (ACL) injuries are prevalent and represent a significant socioeconomic burden, as ACL injuries account for nearly 60% of all knees joint traumas. The purpose of this study is to emphasize the role of arthroscopic ACL reconstruction and the challenges in postoperative pain management. Methods: This study involved 90 patients undergoing ACL reconstruction, categorized into three groups receiving different pain management protocols. The focus was on evaluating the efficacy of multimodal analgesia using lidocaine and magnesium sulfate. The main outcome was pain assessment using the Visual Analog Scale (VAS). Results: Patients receiving fentanyl, lidocaine, and magnesium sulfate (FLM) reported significantly lower pain scores in the postoperative period. Minimal use of additional opioids was observed, suggesting effective pain management with the multimodal analgesia regimen. Conclusions: The study showed that multimodal analgesia, including FLM, effectively manages postoperative pain following ACL reconstruction. This study showed significantly lower pain scores with FLM, highlighting its potential in early postoperative pain relief. Future research should consider long-term outcomes and cost-effectiveness, emphasizing the need for more comprehensive evaluations of multimodal analgesia's impact. [ABSTRACT FROM AUTHOR]

Background: Bone–patellar tendon–bone (BPTB) and double-looped semitendinosus and gracilis (hamstring) grafts are commonly used for anterior cruciate ligament (ACL) reconstruction. Short-term and midterm studies show little or no differences between the 2 grafts; however, there are only a few long-term studies to compare results between the 2 grafts. Purpose: To compare the results after using either BPTB grafts or hamstring tendon grafts 18 years after ACL reconstruction. Study Design: Randomized controlled trial; Level of evidence 2. Methods: A total of 114 patients with ACL rupture between 2001 and 2004 were randomized to reconstruction with either a BPTB graft or a hamstring tendon graft. Patients were operated on at 4 major hospitals. The 18-year follow-up evaluation included anterior knee laxity measured with a KT-1000 arthrometer, defined as the primary outcome, while clinical examination (Lachman and pivot-shift tests), isokinetic testing of muscle strength, patient-reported outcome measures, and an assessment of radiographic osteoarthritis using the Kellgren-Lawrence classification were defined as secondary outcomes. Results: A total of 96 patients (84%, 47 BPTB and 49 hamstring grafts) were available for follow-up, 71 of these for clinical examination. Seven of 96 patients were excluded for ACL revision (n = 5) or knee replacement (n = 2) surgery. In total, 25 patients (10 BPTB and 15 hamstring grafts) had undergone additional surgery other than ACL revision or total knee arthroplasty. There were no significant differences between the groups in terms of anterior laxity test with KT-1000 arthrometer (primary outcome). In secondary outcomes, no significant differences between groups were reported regarding clinical examination, patient-reported outcome scores, or radiographic osteoarthritis (Kellgren-Lawrence grade 2-4 for patellofemoral joint [18 hamstring and 14 BPTB] or tibiofemoral joint [20 hamstring and 19 BPTB]), while isokinetic testing revealed that the hamstring group had a 10.7% reduction in mean peak flexion torque compared with the BPTB group at 60 deg/s (df = 59; P =.011). At 60 deg/s the mean total flexion work in the hamstring group was reduced by 17.2% compared with the BPTB group (df = 59; P =.002). Conclusion: The flexion strength in the hamstring group was significantly reduced in the operated knee after 18 years. There were no significant differences between the groups regarding subjective outcomes, patient-reported outcomes, range of motion, clinical and instrumented knee laxity, and the development of osteoarthritis. Registration: NCT05876013 (ClinicalTrials.gov identifier). [ABSTRACT FROM AUTHOR]

Anterior cruciate ligament (ACL) plays an important role in stabilising the knee joint, prevents excessive anterior translation of the tibia, and provides rotational stability. ACL injuries commonly occur as a result of rapid deceleration, sudden change in direction, or direct impact to the knee during sports activities. Although several deep learning techniques have recently been applied in the detection of ACL tears, challenges such as effective slice filtering and the nuanced relationship between varying tear grades still remain underexplored. This study used an advanced deep learning model that integrated a T-distribution-based slice attention filtering mechanism with a penalty weight loss function to improve the performance for detection of ACL tears. A T-distribution slice attention module was effectively utilised to develop a robust slice filtering system of the deep learning model. By incorporating class relationships and substituting the conventional cross-entropy loss with a penalty weight loss function, the classification accuracy of our model is markedly increased. The combination of slice filtering and penalty weight loss shows significant improvements in diagnostic performance across six different backbone networks. In particular, the VGG-Slice-Weight model provided an area score of 0.9590 under the receiver operating characteristic curve (AUC). The deep learning framework used in this study offers an effective diagnostic tool that supports better ACL injury detection in clinical diagnosis practice. [ABSTRACT FROM AUTHOR]