BACKGROUND:Mn can participate in oxidation-reduction reactions in various organisms.For example,as a metal-assisted group in superoxide dismutase 2,Mn plays a role in helping to remove reactive oxygen species.Therefore,the development of novel anti-oxidative stress materials containing Mn has become a research focus in recent years.OBJECTIVE:To investigate the protective effect of Mn bioceramic powder material on oxidative stress damage to chondrocytes by reducing the reactive oxygen species pathway.METHODS:Bioceramic powders containing Mn were prepared by molten salt method.Primary mouse chondrocytes were isolated and cultured.Bioceramic powder containing 0,0.15,and 0.30 mg/mL of Mn was added into H2O2 solution.The H2O2 clearance rate was detected after incubation without light.The passage 2 to passage 4 chondrocytes were co-cultured with complete media containing Mn-containing bioceramic powder with different mass concentrations(0,0.15,and 0.30 mg/mL).Cell viability was detected by cell live/dead staining.The passage 2-4 chondrocytes(or cartilage tissue)were divided into four groups for intervention:Complete culture medium was added to the blank control group.The H2O2 group was added and cultured with complete medium containing H2O2.H2O2+low mass concentration Mn powder group was cultured by adding H2O2+0.15 mg/mL Mn-containing bioceramic powder.The complete medium containing H2O2+0.30 mg/mL Mn-containing bioceramic powder was added to the H2O2+high mass concentration Mn powder group.Viability of chondrocytes was detected by CCK-8 assay.Generation of reactive oxygen species of chondrocytes was detected by 2,7-dichlorofluorescein diacetate probe.Expression of chondrocyte-related factors was detected by qRT-PCR.The tissue structure and function of cartilage were detected by toluidine blue staining.RESULTS AND CONCLUSION:(1)Both doses of Mn-containing bioceramic powders could significantly remove H2O2 in vitro,and they were concentration dependent.The results of cell live/death staining showed that 0.15 mg/mL bioceramic powder containing Mn had chondrocyte safety,and 0.30 mg/mL bioceramic powder containing Mn had chondrocytotoxicity.(2)The results of CCK-8 assay showed that the two mass concentrations of Mn-containing bioceramic powders could significantly reduce the inhibitory effect of H2O2 on chondrocyte viability,and inhibit the generation of reactive oxygen species induced by H2O2 in chondrocytes in a mass concentration dependent manner.Both kinds of Mn-containing bioceramic powders could reverse the H2O2-induced increase of mRNA expression of a disintegrin and metalloproteinase with thrombospondin motifs-5 and decrease of proteoglycan mRNA expression in chondrocytes.(3)Toluidine blue staining results showed that both concentrations of Mn-containing bioceramic powder could protect the integrity of cartilage tissue structure under oxidative stress,and 0.30 mg/mL of Mn-containing bioceramic powder could also reduce the functional damage of cartilage tissue.(4)The results indicate that the Mn-containing bioceramic powder can protect chondrocytes under oxidative stress by clearing reactive oxygen species,maintaining the extracellular matrix homeostasis.However,0.30 mg/mL Mn-containing bioceramic powder has certain chondrocytotoxicity,so 0.15 mg/mL Mn-containing bioceramic powder is preferred for follow-up studies.

With the rapid development of competitive sports, the incidence of anterior cruciate ligament (ACL) injury is on the rise. Such injuries may shorten athletes′ career and lead to other long-term adverse consequences. Although athletes generally recover well after ACL reconstruction, many still struggle to return to their pre-injury performance levels. Advances in the understanding of ACL anatomy and injury mechanisms, along with the evolution of surgical techniques and rehabilitation methods, have provided more individualized and tailored options for athletes following ACL injuries. However, there is currently no consensus in China regarding surgical and rehabilitation strategies for competitive athletes aiming to return to sports after ACL injuries. To this end, the Sports Medicine Committee of the Chinese Research Hospital Association and the Editorial Board of the Chinese Journal of Trauma jointly formulated the Expert consensus on surgical treatment and rehabilitation for competitive sports athletes returning to sports after anterior cruciate ligament injury ( version 2025), and presented 14 recommendations covering surgical indications, preoperative rehabilitation, surgical timing, surgical strategies and postoperative rehabilitation strategies, aiming to improve the surgical treatment and rehabilitation system for ACL injuries in competitive athletes and facilitate their return to high-level sports performance after injury.

BACKGROUND: The achievement of an optimal return to sport (RTS) has remained a key goal after sports-related injuries, with the ongoing debate on the effectiveness of different surgical approaches for anterior cruciate ligament (ACL) rupture. This study aims to assess clinical outcomes and RTS across various surgical methods, such as anatomical single-bundle reconstruction (ASBR), central-axial single-bundle reconstruction (CASBR), and double-bundle reconstruction (DBR). METHODS: A randomized clinical trial was conducted, comprising 191 patients who underwent ACL rupture. These patients were divided into three groups based on the ACL reconstruction techniques they received (ASBR, CASBR, DBR). Over the 2-year follow-up period, the study assessed RTS through four single-hop tests, isokinetic extension tests, and limb asymmetry indices. Postoperative graft status was determined using the signal-to-noise quotient (SNQ), while knee function was evaluated using the International Knee Documentation Committee 2000 (IKDC-2000) score, Lysholm score, Tegner score, and degree of knee laxity. A binary logistic regression model was developed to forecast the factors influencing ideal RTS. RESULTS: DBR (67.63%) and CASBR (58.00%) exhibited higher RTS passing rates compared to ASBR (30.39%; χ2 = 19.57, P <0.05). Quadriceps strength symmetry in the lower limbs was identified as the key determinant of RTS ( χ2 = 17.08, P <0.05). The RTS rate was influenced by SNQs of the graft's tibial site (odds ratio: 0.544) and quadriceps strength of the reconstructed knee joint at 60°/s (odds ratio: 6.346). Notably, the DBR group showed enhanced knee stability, evidenced by superior results in the Lachman test ( χ2 = 13.49, P <0.01), objective IKDC-2000 ( χ2 = 27.02, P = 0.002), and anterior instability test ( χ2 = 9.46, P <0.01). Furthermore, DBR demonstrated superior clinical outcomes based on the Lysholm score (DBR: 89.57 ± 7.72, CASBR: 83.00 ± 12.71, ASBR: 83.21 ± 11.95; F = 10.452, P <0.01) and IKDC-2000 score (DBR: 90.95 ± 7.00, CASBR: 84.64 ± 12.68, ASBR: 83.63 ± 11.41; F = 11.78, P <0.01). CONCLUSION: For patients with ACL rupture, more ideal RTS rate and clinical outcomes were shown in the DBR group than in the ASBR and CASBR groups. Autograft status and quadriceps strength are postively related to RTS. TRIAL REGISTRATION ClinicalTrials.gov (NCT05400460).
Humans ; Anterior Cruciate Ligament Reconstruction/methods* ; Male ; Female ; Adult ; Anterior Cruciate Ligament Injuries/surgery* ; Young Adult ; Return to Sport ; Adolescent ; Anterior Cruciate Ligament/surgery* ; Treatment Outcome

BACKGROUND:Mn can participate in oxidation-reduction reactions in various organisms.For example,as a metal-assisted group in superoxide dismutase 2,Mn plays a role in helping to remove reactive oxygen species.Therefore,the development of novel anti-oxidative stress materials containing Mn has become a research focus in recent years.OBJECTIVE:To investigate the protective effect of Mn bioceramic powder material on oxidative stress damage to chondrocytes by reducing the reactive oxygen species pathway.METHODS:Bioceramic powders containing Mn were prepared by molten salt method.Primary mouse chondrocytes were isolated and cultured.Bioceramic powder containing 0,0.15,and 0.30 mg/mL of Mn was added into H2O2 solution.The H2O2 clearance rate was detected after incubation without light.The passage 2 to passage 4 chondrocytes were co-cultured with complete media containing Mn-containing bioceramic powder with different mass concentrations(0,0.15,and 0.30 mg/mL).Cell viability was detected by cell live/dead staining.The passage 2-4 chondrocytes(or cartilage tissue)were divided into four groups for intervention:Complete culture medium was added to the blank control group.The H2O2 group was added and cultured with complete medium containing H2O2.H2O2+low mass concentration Mn powder group was cultured by adding H2O2+0.15 mg/mL Mn-containing bioceramic powder.The complete medium containing H2O2+0.30 mg/mL Mn-containing bioceramic powder was added to the H2O2+high mass concentration Mn powder group.Viability of chondrocytes was detected by CCK-8 assay.Generation of reactive oxygen species of chondrocytes was detected by 2,7-dichlorofluorescein diacetate probe.Expression of chondrocyte-related factors was detected by qRT-PCR.The tissue structure and function of cartilage were detected by toluidine blue staining.RESULTS AND CONCLUSION:(1)Both doses of Mn-containing bioceramic powders could significantly remove H2O2 in vitro,and they were concentration dependent.The results of cell live/death staining showed that 0.15 mg/mL bioceramic powder containing Mn had chondrocyte safety,and 0.30 mg/mL bioceramic powder containing Mn had chondrocytotoxicity.(2)The results of CCK-8 assay showed that the two mass concentrations of Mn-containing bioceramic powders could significantly reduce the inhibitory effect of H2O2 on chondrocyte viability,and inhibit the generation of reactive oxygen species induced by H2O2 in chondrocytes in a mass concentration dependent manner.Both kinds of Mn-containing bioceramic powders could reverse the H2O2-induced increase of mRNA expression of a disintegrin and metalloproteinase with thrombospondin motifs-5 and decrease of proteoglycan mRNA expression in chondrocytes.(3)Toluidine blue staining results showed that both concentrations of Mn-containing bioceramic powder could protect the integrity of cartilage tissue structure under oxidative stress,and 0.30 mg/mL of Mn-containing bioceramic powder could also reduce the functional damage of cartilage tissue.(4)The results indicate that the Mn-containing bioceramic powder can protect chondrocytes under oxidative stress by clearing reactive oxygen species,maintaining the extracellular matrix homeostasis.However,0.30 mg/mL Mn-containing bioceramic powder has certain chondrocytotoxicity,so 0.15 mg/mL Mn-containing bioceramic powder is preferred for follow-up studies.

With the rapid development of competitive sports, the incidence of anterior cruciate ligament (ACL) injury is on the rise. Such injuries may shorten athletes′ career and lead to other long-term adverse consequences. Although athletes generally recover well after ACL reconstruction, many still struggle to return to their pre-injury performance levels. Advances in the understanding of ACL anatomy and injury mechanisms, along with the evolution of surgical techniques and rehabilitation methods, have provided more individualized and tailored options for athletes following ACL injuries. However, there is currently no consensus in China regarding surgical and rehabilitation strategies for competitive athletes aiming to return to sports after ACL injuries. To this end, the Sports Medicine Committee of the Chinese Research Hospital Association and the Editorial Board of the Chinese Journal of Trauma jointly formulated the Expert consensus on surgical treatment and rehabilitation for competitive sports athletes returning to sports after anterior cruciate ligament injury ( version 2025), and presented 14 recommendations covering surgical indications, preoperative rehabilitation, surgical timing, surgical strategies and postoperative rehabilitation strategies, aiming to improve the surgical treatment and rehabilitation system for ACL injuries in competitive athletes and facilitate their return to high-level sports performance after injury.

Background::To perform anatomical anterior cruciate ligament reconstruction (ACLR), tunnels should be placed relatively higher in the femoral anterior cruciate ligament (ACL) footprint based on the findings of direct and indirect femoral insertion. But the clinical results of higher femoral tunnels (HFT) in double-bundle ACLR (DB-ACLR) remain unclear. The purpose was to investigate the clinical results of HFT and lower femoral tunnels (LFT) in DB-ACLR.Methods::From September 2014 to February 2016, 83 patients who underwent DB-ACLR and met the inclusion and exclusion criteria were divided into HFT-ACLR (group 1, n = 37) and LFT-ACLR (group 2, n = 46) according to the position of femoral tunnels. Preoperatively and at the final follow-up, clinical scores were evaluated with International Knee Documentation Committee (IKDC), Tegner activity, and Lysholm score. The stability of the knee was evaluated with KT-2000, Lachman test, and pivot-shift test. Cartilage degeneration grades of the International Cartilage Repair Society (ICRS) were evaluated on magnetic resonance imaging (MRI). Graft tension, continuity, and synovialization were evaluated by second-look arthroscopy. Return-to-sports was assessed at the final follow-up. Results::Significantly better improvement were found for KT-2000, Lachman test, and pivot-shift test postoperatively in group 1 ( P >0.05). Posterolateral bundles (PL) showed significantly better results in second-look arthroscopy regarding graft tension, continuity, and synovialization ( P <0.05), but not in anteromedial bundles in group 1. At the final follow-up, cartilage worsening was observed in groups 1 and 2, but it did not reach a stastistically significant difference ( P >0.05). No statistically significant differences were found in IKDC subjective score, Tegner activity, and Lysholm score between the two groups. Higher return-to-sports rate was found in group 1 with 86.8% (32/37) vs. 65.2% (30/46) in group 2 ( P = 0.027). Conclusion::The HFT-ACLR group showed better stability results, better PL, and higher return-to-sports rate compared to the LFT-ACLR group.

Humans ; Arthroplasty, Replacement, Knee ; Follow-Up Studies ; Cohort Studies ; Treatment Outcome ; Minimally Invasive Surgical Procedures ; Knee Joint/surgery* ; Knee Prosthesis ; Osteoarthritis, Knee/surgery*

Objective:To characterize the femoral dense insertion (FDI) of the anterior cruciate ligament (ACL) using 3D magnetic resonance imaging (MRI) so as to guide the femoral tunnel placement in ACL reconstruction.Methods:The 3D MRI data of the contralateral healthy knees were collected from 20 young and middle-aged patients who had been followed up for 2 years at the Department of Sports Medicine, Peking University Third Hospital from June to October 2019 after ACL reconstruction. There were 10 males and 10 females with an age of (34.5±7.8) years. The 3D models of FDI of ACL, as well as of the lateral femoral condyle and its cartilage were reconstructed using Mimics 15.01. The heights and front and rear positions of anteromedial (AM) bundle, center, and posterolateral (PL) bundle of FDI were measured with reference to the apex of deep cartilage (ADC), the deep cortical border of the lateral condyle, and the shallow and inferior cartilage margins.Results:In 3D MRI models, dense fibers of ACL femoral insertion were near the shallow and inferior cartilage margins to the shallow side, and extended obliquely deep and superior toward the over-the-top (OTP) in a band-like shape. The oblique angle was 12.5°. The AM bundle, FDI center, and PL bundle were all higher than ADC, being (4.5±0.7) mm, (3.5±0.8) mm and (2.2±0.6) mm away from ADC, respectively. The median distances to the deep cortical border of the lateral condyle and the shallow cartilage margin were (6.9±1.2) mm and (16.4±1.8) mm for the AM bundle, (11.0±1.4) and (12.1±1.6) mm for the FDI center, and (14.9±1.8) mm and (8.0±1.3) mm for the PL bundle.Conclusions:Dense fibers of ACL femoral insertion are near the shallow and inferior cartilage margin to the shallow side, and extend obliquely deep and superior toward the OTP in a band-like shape. As the height and depth measurements of the FDI in 3D MRI models supplement to the anatomy of ACL femoral insertion, they could be used to guide femoral tunnel placement in ACL reconstruction.

The anterior cruciate ligament (ACL) injury is a common sports injury that has a significant impact on knee function and patients′ mobility. With the popularity of national fitness campaign in China, the incidence of ACL injury is increasing year by year. Currently, there still lacks clinical standards or guidelines on how to choose appropriate treatment methods, surgical plans and rehabilitation protocols for ACL injury. In order to timely reflect the new treatment concept of ACL injury, standardize its diagnosis and treatment and improve the curative effect, the Sports Medicine Society of Chinese Research Hospital Association and the Editorial Board of Chinese Journal of Trauma organized domestic orthopedic and sports medicine experts to formulate the "clinical evidence-based guideline for the diagnosis and treatment of anterior cruciate ligament injury (2022 version)" based on the level of evidence-based medicine and in compliance with the principle of scientificity, practicability and advancement. The present guideline includes 12 recommendations for the diagnosis, treatment and rehabilitation of ACL injury in order to provide guidance and assistance for the clinical diagnosis and treatment of ACL injury in China.

Objective To compare the femur tibia angle(FTA) and tibia tubercle to trochlear groove (TT-TG) measured on the magnetic resonance imaging(MRI) between patients with anterior cruciate ligament(ACL) rupture and healthy controls with intact ACL,and to observe the change of the tibia-femur rotation and explore its relationship with the patellofemoral cartilage injury.Methods Fifty patients with ACL ruptures were divided into an experimental group,while another 50 healthy counterparts were chosen into a control group.All subjects were given MRI to get FTA and TT-TG.For the experimental group,all parameters were measured before and after ACL reconstruction.The results were analyzed by variance analysis and t test.Results MRI measurements showed that the average FTA in the experimental group was 6.5° ± 6.1° and 6.0° ± 5.6° before and after the ACL reconstruction,significantly higher than that in the control group,which was 3.6° ± 4.9° (P=0.0003 and P=0.033,respectively).No significant differences were found in the average TT-TG of the experimental group,6.4 ± 3.3 mm before ACL reconstruction and 6.9 mm ± 4.0 mm after ACL reconstruction,and that of the control group,6.3 ± 3.6 mm(P=0.678).Moreover,all patients in the experimental group underwent a second check under the arthroscopy,which revealed that the patellofemoral cartilage injury was aggravat ed in 26 patients measured by the Outerbridge grading.However,there was no significant difference in FTA and TT-TG between patients with and without aggravated patellofemoral cartilage degeneration.Conclusions After ACL reconstruction,the external rotation angle of the knee could not completely recover to the normal level with the knee extension at 0°.Patellofemoral cartilage degeneration after the ACL reconstruction is caused by many factors.The results of the second arthroscopy after the ACL reconstruction find no relationship between patellofemoral cartilage degeneration and the increased tibia external rotation angle relative to the femur.Moreover,after the ACL reconstruction,if the femur tibia angle is bigger than the range of motion of the knee,it cannot be concluded that the anterior cruciate ligament is reruptured.