Diagnosis and treatment of anterior cruciate ligament injuries: Consensus of Chinese experts part II: Graft selection and clinical outcome evaluation.

Background: In the recent decade, there has been substantial progress in the technologies and philosophies associated with diagnosing and treating anterior cruciate ligament (ACL) injuries in China. The therapeutic efficacy of ACL reconstruction in re-establishing the stability of the knee joint has garnered widespread acknowledgment. However, the path toward standardizing diagnostic and treatment protocols remains to be further developed and refined. Objective: In this context, the Chinese Association of Orthopaedic Surgeons (CAOS) and the Chinese Society of Sports Medicine (CSSM) collaboratively developed an expert consensus on diagnosing and treating ACL injury, aiming to enhance medical quality through refining professional standards. Methods: The consensus drafting team invited experts across the Greater China region, including the mainland, Hong Kong, Macau, and Taiwan, to formulate and review the consensus using a modified Delphi method as a standardization approach. As members of the CSSM Lower Limb Study Group and the CAOS Arthroscopy and Sports Medicine Study Group, invited experts concentrated on two pivotal issues: "Graft Selection" and "Clinical Outcome Evaluation" during the second part of the consensus development. Results: This focused discussion ultimately led to a strong consensus on nine specific consensus terms. Conclusion: The consensus clearly states that ACL reconstruction has no definitive "gold standard" graft choice. Autografts have advantages in healing capability but are limited in availability and have potential donor site morbidities; allografts reduce surgical trauma but incur additional costs, and there are concerns about slow healing, quality control issues, and a higher failure rate in young athletes; synthetic ligaments allow for early rehabilitation and fast return to sport, but the surgery is technically demanding and incurs additional costs. When choosing a graft, one should comprehensively consider the graft's characteristics, the doctor's technical ability, and the patient's needs. When evaluating clinical outcomes, it is essential to ensure an adequate sample size and follow-up rate, and the research should include patient subjective scoring, joint function and stability, complications, surgical failure, and the return to sport results. Medium and long-term follow-ups should not overlook the assessment of knee osteoarthritis.

Finite element analysis of anterior cruciate ligament reconstruction techniques: A comparison of the mechanical properties of all-inside fixation and traditional fixation.

Objective: The main purpose of this study was to explore the mechanical properties of the anterior cruciate ligament and its attachments following reconstruction with the all-inside technique after anterior cruciate ligament injury. Methods: Knee joint computed tomography data were collected from healthy volunteers, and knee joint models were created using Mimics software. A normal knee joint model, an all-inside reconstructed anterior cruciate ligament model, and a traditional reconstructed anterior cruciate ligament model were established. A tensile force of 134 N and a bending moment of 5 N/m were applied at the anterior aspect of the proximal tibia in these three models. The knee joint was subjected to external rotation, internal rotation, varus, valgus, flexion, and extension under this bending moment. The magnitude and distribution of stress on the ligament or graft and the magnitude and distribution of stress on the graft attachments were observed under different loading conditions. Results: Under different external forces, the maximum stress on the ligament in the normal model fluctuated from 1.949 to 18.302 MPa, with an uncertain distribution of maximum stress. The maximum stress on the graft in the all-inside reconstructed anterior cruciate ligament model fluctuated from 0.705 to 3.465 MPa and was mainly distributed at the junction of the graft and the tibial footprint. In the traditional reconstructed anterior cruciate ligament model, the maximum stress on the graft fluctuated from 5.012 to 59.269 MPa and was primarily distributed at the junction of the interference screw and the graft. The concentration of stress on the loop and plate in the all-inside reconstructed anterior cruciate ligament model fluctuated from 70.461 to 346.363 MPa, with maximum stress distributed at the junction of the loop and the tibial surface. The maximum stress on the interference screw in the traditional reconstructed anterior cruciate ligament model fluctuated from 10.184 to 92.298 MPa, with maximum stress primarily distributed at the end of the interference screw. Conclusion: Under different external forces, the graft used in all-inside anterior cruciate ligament reconstruction is subjected to fewer external forces than that used in traditional anterior cruciate ligament reconstruction, which may indicate a relatively stable mechanical environment. The strength of the loop and plate can theoretically tolerate daily knee joint movements of patients without injury.

Bone Morphogenetic Protein 7-Loaded Gelatin Methacrylate/Oxidized Sodium Alginate/Nano-Hydroxyapatite Composite Hydrogel for Bone Tissue Engineering.

Background: Bone tissue engineering (BTE) is a promising alternative to autologous bone grafting for the clinical treatment of bone defects, and inorganic/organic composite hydrogels as BTE scaffolds are a hot spot in current research. The construction of nano-hydroxyapatite/gelatin methacrylate/oxidized sodium alginate (nHAP/GelMA/OSA), abbreviated as HGO, composite hydrogels loaded with bone morphogenetic protein 7 (BMP7) will provide a suitable 3D microenvironment to promote cell aggregation, proliferation, and differentiation, thus facilitating bone repair and regeneration. Methods: Dually-crosslinked hydrogels were fabricated by combining GelMA and OSA, while HGO hydrogels were formulated by incorporating varying amounts of nHAP. The hydrogels were physically and chemically characterized followed by the assessment of their biocompatibility. BMP7-HGO (BHGO) hydrogels were fabricated by incorporating suitable concentrations of BMP7 into HGO hydrogels. The osteogenic potential of BHGO hydrogels was then validated through in vitro experiments and using rat femoral defect models. Results: The addition of nHAP significantly improved the physical properties of the hydrogel, and the composite hydrogel with 10% nHAP demonstrated the best overall performance among all groups. The selected concentration of HGO hydrogel served as a carrier for BMP7 loading and was evaluated for its osteogenic potential both in vivo and in vitro. The BHGO hydrogel demonstrated superior in vitro osteogenic induction and in vivo potential for repairing bone tissue compared to the outcomes observed in the blank control, BMP7, and HGO groups. Conclusion: Using hydrogel containing 10% HGO appears promising for bone tissue engineering scaffolds, especially when loaded with BMP7 to boost its osteogenic potential. However, further investigation is needed to optimize the GelMA, OSA, and nHAP ratios, along with the BMP7 concentration, to maximize the osteogenic potential.

[Hip joint biomechanical analysis of the acetabular anatomical reconstruction and nonanatomical reconstruction in total hip arthroplasty for Crowe type â ¢ developmental dysplasia of the hip by finite element method].

OBJECTIVE: To analyze the hip joint biomechanics of the acetabular anatomical reconstruction and nonanatomical reconstruction in total hip arthroplasty (THA) for Crowe type Ⅲ developmental dysplasia of the hip (DDH) by finite element method, which provided theoretical foundation and experimental basis for the anatomical acetabular reconstruction during THA in clinical practice. METHODS: One patient with left end-stage hip arthritis secondary to Crowe type Ⅲ DDH was selected in this study, who underwent total hip arthroplasty in the orthopedic department of the First Affiliated Hospital of Bengbu Medical College in April 2020. This patient was female, 57 years old. The preoperative and postoperative three dimentional CT scan of the patient's pelvis were performed. Fourteen acetabular cup models with different anteversion, inclination and rotation center height were established in Mimics and 3-Matic software. The boundary and load conditions were set in Abaqus software. The Von Mises and stress distribution of the hip joint were calculated and observed. RESULTS: In the Crowe type Ⅲ DDH THA, if the hip rotation center was restored anatomically and the acetabular cup's inclination was set as 40°, the cup's anteversion varied from 5° to 25°, the lowest Von Mises value of acetabular cup and polyethylene liner occured in 20°anteversioin;if the hip rotation center was restored anatomically and the acetabular cup's anteversion was set as 15°, the cup's inclination varied from 35° to 55°, the lowest Von Mises value of acetabular cup and polyethylene liner occured in 35° inclination;if the acetabular cup's anteversion and inclination were set as 15°and 40°respectively, the up migration of hip rotaion center varied from 0 mm to 20 mm, the lowest Von Mises value of acetabular cup and polyethylene liner occured in 10 mm up migration. In all fourteen models, the Von Mises value of the acetabulum, acetabulum cup and polyethylene liner were lowest when the acetabular cup's anteversion and inlcination were 15°, 35° respectively, as well as the rotation center was restored anatomically. CONCLUSION: In total hip arthroplasty for Crowe type Ⅲ DDH, the anatomical restoration of hip rotation center with 15° anteversion and 35° inclination of the acetabular cup are suggested, bone graft above the acetabular cup and additional screws are recommended simultaneously to further reduce the Von Mises of hip joint.

[Correlation between femoral offset, rotation center and leg length discrepancy after total hip arthroplasty based on digital analysis].

OBJECTIVE: CT scans combined with Mimics software were used to measure femoral offset (FO), rotation center height (RCH) and lower leg length discrepancy (LLD) following total hip arthroplasty (THA), and the relationship between FO, RCH and LLD after THA is discussed. METHODS: Retrospective analysis was performed on 40 patients with unilateral THA who met standard cases from October 2020 to June 2022. There were 21 males and 19 females, 18 patients on the left side and 22 patients on the right side, aged range from 30 to 81 years old, with an average age of (58.90 ±14.13) years old, BMI ranged from 17.3 to 31.5 kg·m-2 with an average of (25.3±3.4) kg·m-2. There were 30 cases of femoral head necrosis (Ficat type Ⅳ), 2 cases of hip osteoarthritis (Tönnis type Ⅲ), 2 cases of developmental hip dislocation combined with end-stage osteoarthritis (Crowe type Ⅲ), and 6 cases of femoral neck fracture (Garden type Ⅳ). Three-dimensional CT reconstruction of pelvis was taken preoperative and postoperative, and three-dimensional reconstruction model was established after processing by Mimics software. FO, RCH and LLD were measured on the model. The criteria for FO reconstruction were as follows:postoperative bilateral FO difference less than 5 mm;the standard for equal length of both lower limbs was as follows:postoperative LLD difference less than 5 mm. RESULTS: Bilateral FO difference was positively correlated with LLD (r=0.744, P<0.001). Chi-square test was performed between the FO reconstructed group and the non-reconstructed eccentricity group:The results showed that the isometric ratio of lower limbs in the FO reconstructed group was significantly higher than that in the FO reconstructed group (χ2=6.320, P=0.012). The bilateral RCH difference was significantly negatively correlated with LLD(r=-0.877, P<0.001). There is a linear relationship between bilateral FO difference and bilateral RCH difference and postoperative LLD, and the linear regression equation is satisfied:postoperative LLD=0.038x-0.099y+0.257(x:postoperative bilateral FO difference, y:postoperative bilateral RCH difference; Unit:cm), F=77.993, R2=0.808, P=0.009. CONCLUSION: After THA, LLD increased with the increase of FO and decreased with the increase of RCH. The effect of lower limb isometric length can be obtained more easily by reconstruction of FO. There is a linear relationship between the bilateral FO difference and the bilateral RCH difference after THA and LLD, and the regression equation can provide a theoretical reference for judging LLD.

[Application and research progress of artificial intelligence technology in trauma treatment].

Objective: To review the application and research progress of artificial intelligence (AI) technology in trauma treatment. Methods: The recent research literature on the application of AI and related technologies in trauma treatment was reviewed and summarized in terms of prehospital assistance, in-hospital emergency care, and post-traumatic stress disorder risk regression prediction, meanwhile, the development trend of AI technology in trauma treatment were outlooked. Results: The AI technology can rapidly analyze and manage large amount of clinical data to help doctors identify patients' situation of trauma and predict the risk of possible complications more accurately. The application of AI technology in surgical assistance and robotic operations can achieve precise surgical plan and treatment, reduce surgical risks, and shorten the operation time, so as to improve the efficiency and long-term effectiveness of the trauma treatment. Conclusion: There is a promising future for the application of AI technology in the trauma treatment. However, it is still in the stage of exploration and development, and there are many difficulties of historical data bias, application condition limitations, as well as ethical and moral issues need to be solved.

Protective effect of bone morphogenetic protein-7 induced differentiation of bone marrow mesenchymal stem cells in rat with acute spinal cord injury.

The principal aim of present study was to assess the therapeutic efficacy of bone morphogenetic protein-7 (BMP-7) induced differentiation of bone marrow mesenchymal stem cells (BMSCs) in a rat acute spinal cord injury (SCI) model. BMSCs were isolated from rats, and then divided into a control and a BMP-7 induction groups. The proliferation ability of BMSCs and glial cell markers were determined. Forty Sprague-Dawley (SD) rats were randomly divided into sham, SCI, BMSC, and BMP7 + BMSC groups (n = 10). Among these rats, the recovery of hind limb motor function, the pathological related markers, and motor evoked potentials (MEP) were identified. BMSCs differentiated into neuron-like cells after the introduction of exogenous BMP-7. Interestingly, the expression levels of MAP-2 and Nestin increased, whereas the expression level of GFAP decreased after the treatment with exogenous BMP-7. Furthermore, the Basso, Beattie, and Bresnahan (BBB) score reached 19.33 ± 0.58 in the BMP-7 + BMSC group at day 42. Nissl bodies in the model group were reduced compared to the sham group. After 42 days, in both the BMSC and BMP-7 + BMSC groups, the number of Nissl bodies increased. This is especially so for the number of Nissl bodies in the BMP-7 + BMSC group, which was more than that in the BMSC group. The expression of Tuj-1 and MBP in BMP-7 + BMSC group increased, whereas the expression of GFAP decreased. Moreover, the MEP waveform decreased significantly after surgery. Furthermore, the waveform was wider and the amplitude was higher in BMP-7 + BMSC group than that in BMSC group. BMP-7 promotes BMSC proliferation, induces the differentiation of BMSCsinto neuron-like cells, and inhibits the formation of glial scar. BMP-7 plays a confident role in the recovery of SCI rats.

Differentiation of rat bone marrow mesenchymal stem cells into neurons induced by bone morphogenetic protein 7 in vitro.

OBJECTIVES: Spinal cord injury (SCI) is caused by external direct or indirect factors with high disability rate, which may even endanger the life of patients. To explore the role of bone morphogenetic protein 7 (BMP-7) in the differentiation of rat bone marrow mesenchymal stem cells (BMSCs) into neurons in vitro. METHODS: BMSCs were isolated and cultured by whole bone marrow adherence method. Adipogenic induction and osteogenic differentiation were used to test the multi⁃directional differentiation ability of BMSCs. RESULTS: After 28 days of adipogenic induction, BMSCs showed lipid droplets in the cytoplasm. After osteogenic induction, there were opaque lumps of mineral nodules in BMSCs. There were also orange-red or red mineral nodules in the extracellular matrix. The BMSCs in the 75 ng/ml BMP-7 group were morphologically similar to the neurons. After induction with BMP-7 for 2 h, the NF200 mRNA expression was higher, mRNA expression levels of SYN1, MAP2 and GFAP were higher. Positive rate of immunofluorescence staining in the BMP-7 group was notably increased. The positive rate of NSE immunofluorescence staining in the BMP-7 group was higher. CONCLUSION: BMP-7 can induce rat BMSCs to differentiate into neurons in vitro.

Bone Morphogenetic Protein-7 (BMP-7) Promotes Neuronal Differentiation of Bone Marrow Mesenchymal Stem Cells (BMSCs) In Vitro.

This study is aimed at investigating the effects of bone morphogenetic protein-7 (BMP-7) on the differentiation of bone marrow mesenchymal stem cells (BMSCs) into neuron-like cells in vitro. The rat BMSCs were isolated and identified, which were divided into the control, empty, recombinant rhBMP-7 transfection, and Lv-BMP-7 transfection groups. BMSCs were induced under different conditions. CCK-8 assay was performed to detect cell proliferation. ALP was used to detect cell activity. Cellular morphology after induction was observed. Immunofluorescence was conducted to detect the expression and location of nerve cell markers. Quantitative real-time PCR and Western blot analysis were performed to detect the mRNA and protein expression levels, respectively. The rhBMP-7 and Lv-BMP-7 promoted the proliferation of BMSCs, accompanied with increased ALP activities. Morphological observations revealed that rhBMP-7 and Lv-BMP-7 induced BMSCs to differentiate into neuron-like cells. Immunofluorescence revealed that the rhBMP-7 and Lv-BMP-7 groups showed positive expression of MAP-2 and Nfh in BMSCs. MAP-2 was mainly distributed in the cell body and cellular protrusion, while Nfh was mainly distributed in the cytoplasm and cell protrusion. Positive mRNA and protein expressions of MAP-2 and Nfh were observed in the cells of the rhBMP-7 and Lv-BMP-7 groups, and the expression levels were significantly higher than the control and empty groups. Both exogenous BMP-7 (rhBMP-7) and endogenous BMP-7 (Lv-BMP-7) can induce BMSCs to differentiate into neuron-like cells highly expressing the neuronal markers MAP-2 and Nfh.

Local injection of bone morphogenetic protein 7 promotes neuronal regeneration and motor function recovery after acute spinal cord injury.

After spinal cord injury, the number of glial cells and motor neurons expressing bone morphogenetic protein 7 (BMP7) increases, indicating that upregulation of BMP7 can promote nerve repair. We, therefore, tested whether direct injection of BMP7 into acutely injured rat spinal cord can affect neurological recovery. Allen's impactor was used to create spinal cord injury at T10. The injury site was then injected with 50 ng BMP7 (BMP7 group) or physiological saline (control group) for 7 consecutive days. Electrophysiological examination showed that the amplitude of N1 in motor evoked potentials (MEP) decreased after spinal cord injury. At 8 weeks post-operation, the amplitude of N1 in the BMP7 group was remarkably higher than that at 1 week post-operation and was higher than that of the control group. Basso, Beattie, Bresnahan scale (BBB) scores, hematoxylin-eosin staining, and western blot assay showed that at 1, 2, 4 and 8 weeks post-operation, BBB scores were increased; Nissl body staining was stronger; the number of Nissl-stained bodies was increased; the number of vacuoles gradually decreased; the number of synapses was increased; and the expression of neuronal marker, neurofilament protein 200, was increased in the hind limbs of the BMP7 group compared with the control group. Western blot assay showed that the expression of GFAP protein in BMP7 group and control group did not change significantly and there was no significant difference between the BMP7 and control groups. These data confirmed that local injection of BMP7 can promote neuronal regeneration after spinal cord injury and promote recovery of motor function in rats.

Effect of Id1 knockdown on formation of osteolytic bone lesions by prostate cancer PC3 cells in vivo.

The formation of osteolytic bone lesions is a key process for osteolytic cancer to metastasize to the bone and is under the control of a set of transcription factors. Recently, the inhibitor of differentiation 1 (Id1) has been linked with angiogenesis, tumorigenesis, metastasis and bone formation. However, the function of Id1 during the process of bone destruction caused by cancer in vivo has not yet been elucidated. We, therefore, examined whether and how Id1 affects the ability of cancer to form osteolytic lesion in vivo. The study used a lentiviral vector overexpressing short hairpin RNA (shRNA) targeting Id1 gene. PC3 cells, a prostate cancer cell line, were transduced with Id1 shRNA or negative control (NC) shRNA before implantation in BALB/c mice. Cells were implanted in a tibial injection model. Tumor formation in bone was monitored by X-ray. The relationship between parathyroid hormone-related protein (PTHrP), an osteolytic factor, and Id1 was analyzed by using immunohistochemistry in tissue sections from osteolytic lesion of the BALB/c mice. Our results showed that Id1 shRNA delivery to PC3 cells by lentivirus caused efficient and stable Id1 gene silencing. In the intratibial model, PC3 cells produced primarily osteolytic lesions in the bone. Eleven of 14 mice in Id1 shRNA group but only 4 of 14 mice in the NC shRNA group developed osteolytic lesions with cortical destruction at 4th week. Mice treated with Id1 shRNA had larger tumor volume in the bone and larger cortical destruction. The expression of PTHrP protein in PC3 cells was not affected by Id1 knockdown in vivo. These results indicate that Id1 may down-regulate the ability of PC3 cells to form osteolytic lesions in vivo and the signal pathway needs to be further investigated.