The lumber ligaments play an important role in spinal bsomechanics. The results of three-dimensional finite element analysis showed that one of functions of lumbar ligaments is transmission of the tensile load between the lumbar vertebrae. The anterior longitudinal ligament is loaded in extension of lumbar spine and the resistance to the tensile load in flexion is provided by other ligaments. These ligaments are subject to much more tension with degsneration of the intervertebral disc so that a series of pathological changes occur. Relevant significance in clinical aspect is also discussed.

Objective:To investigate the effect of ultrasound-guided transversus abdominis plane block on intraoperative and postoper-ative analgesia in laparoscopic abdominal surgery.Methods:Sixty ASAⅠ-Ⅱpatients with abdominal tumor,undergoing laparoscopic/robotic surgery were randomly assigned into two groups:one group undergoing general anesthesia(G group)and the other undergo-ing general anesthesia combined with transversus abdominis plane block(G+T group).After induction of general anesthesia in the G+T group,the patients received transversus abdominis plane block with injection of 15 Ml of 0.25% ropivacaine on each side,guided by ultrasound.The operation time,resuscitation time,orientation recovery time,and the dosage of remifentanyl were recorded and com-pared.During surgery,the MAP and HR at different time points(5 min before,after surgical incision;30 min after the surgery begin-ning;surgery finished)between the two groups were recorded and compared.Additionally,the VAS scores at different postoperative time points were compared between the two groups.Results:Compared to the G group,the resuscitation time,orientation recovery time and the dosage of remifentanyl in the G+T group were significantly decreased(P<0.05).In G group,compared to the basic value, the MAP and HR at 5 min and 30 min after surgical incision were significantly increased(P<0.05);whereas in the G+T group,the MAP and HR remained stable at different time points(P>0.05).Moreover,compared to the G group,the VAS score in the G+T group was sig-nificantly lower at 2,6,and 12 hours postoperatively(P<0.05).Conclusions:General anesthesia combined with transversus abdominis plane block in patients undergoing laparoscopic abdominal surgery reduces the intraoperative and postoperative remifentanil con-sumption,improves the efficacy of perioperative analgesia,and enhances the patient's recovery after surgery.

Objective:To investigate the annual amounts of knee and hip arthroplasty in China and their changing trends.Methods:Self-designed questionnaires were conducted by convenience sampling to investigate the annual sales of all brands of artificial joints in China from 2011 to 2019. The data in Beijing were collected from the joint department in all the secondary and tertiary hospitals in Beijing. The national data were collected from the principal of marketing department or sales department of the manufacturer. Statistical analysis was performed subsequently.Results:The number of questionnaire was 541 with recovery rate 87.2%. The annual amounts of knee and hip arthroplasty in China between 2011 and 2019 were 221,920 (2011), 250,473 (2012), 328,192 (2013), 437,100 (2014), 455,640 (2016), 567,397 (2017), 688,583 (2018), 951,986 (2019) respectively. However, the 2015 data was missing. The annual growth rates were 12.87% (2012), 31.03% (2013), 33.18% (2014), 24.53% (2017), 21.36% (2018), 38.25% (2019). The average of annual growth rate between 2011 and 2019 was 19.96%. Amongst the total amounts of joint arthroplasty in China, hip prosthesis (domestic and imported) accounted for 75.72% (2011), 72.61% (2012), 67.73% (2013), 64.74% (2014), 62.47% (2016), 65.04% (2017), 62.78% (2018) and 59.44% (2019), while the domestic prosthesis (hip and knee) engaged 33.15% (2011), 39.27% (2012), 45.16% (2014), 42.19% (2016), 47.55% (2017), 54.33% (2018) and 55.97% (2019). The annual amounts of THA and TKA in Beijing between 2011 and 2019 were 11,077 (2011), 12,005 (2012), 16,822 (2013), 18,147 (2014), 19,102 (2015), 19,247 (2016), 18,467 (2017), 20,258 (2018), 21,381 (2019). The annual growth rates were 8.38% (2012), 40.12%(2013), 7.88% (2014), 5.26% (2015), 0.76% (2016), -4.10% (2017), 9.76% (2018), 5.54% (2019). The average of annual growth rate between 2011 and 2019 was 8.56%. Amongst the total amounts of joint arthroplasty in Beijing, hip prosthesis (domestic and imported) accounted for 48.26% (2011), 48.90% (2012), 46.54% (2013), 46.17% (2014), 46.33%(2015), 45.31%(2016), 43.33% (2017), 41.64% (2018) and 43.66% (2019).Conclusion:The total amounts of joint arthroplasty reached up to 951,986 in 2019 with the average annual growth rate of 19.96% between 2011 and 2019. The national amount of hip and knee arthroplasty increased stably, while the amount of hip and knee arthroplasty in Beijing grew slowly. The number of hip arthroplasty was more than that of knee arthroplasty nationwide, while the trend was converse in Beijing. Domestic prosthesis had a higher growth rate than imported prosthesis. The amount of domestic prosthesis surpassed that of imported prosthesis from 2018.

Objective Objective To evaluate the biomechanical effects of using a new injectable calcium phosphate cement to consolidate the fixation of osteoporotic intertrochanteric fracture. Method Five matched pairs of human cadaver femora were used to produce the model of intertrochanteric fracture. All fractures were fixed with dynamic hip screws(DHS),and divided into two groups. In the CPC consolidation group of each pair, CPC was used to grout the hip screw and to fill the posteromedial defect. All femora were subjected to biomechanical test. Result Under the loading of 500 N, in the CPC consolidation group, the mean axial stiffness was (691.93±18.90) N/mm and the horizontal shear stiffness was (5553.84±27.47) N/mm. The mean lateral and medial strength was 5.15±0.35 MPa and (4.13±0.24) MPa. The torsion stiffness was 0.41 and the ultimate loading was (3580±286)N. In the control group, the mean axial stiffness was (453.45±19.75) N/mm, the horizontal shear stiffness was (3848.87±22.63) N/mm, the mean lateral and medial strength was (3.12±0.37) MPa and (1.80±0.21) MPa, and, the torsion stiffness was 0.35 and the ultimate loading was (2512±189)N. Consolidation fixation with CPC increased each of the biomechanical efficiency（P<0.05）. Conclusion CPC consolidation of osteoprotic femoral head and the medial defect of intertrochanteric fracture could significantly improve the overall stability and decrease the rate of postoperative complication.

The document represented the consensus amongst the professionals from the Society of TMD & Occlusion, Chinese Stomatological Association and provided guidelines with the MRI examination specification and diagnostic criteria of temporomandibular joint disc displacement.

The document represented the consensus amongst the professionals from the Society of TMD & Occlusion, Chinese Stomatological Association and provided guidelines with the cone-beam CT examination specification and diagnostic criteria of temporomandibular disorders.

Temporomandibular joint (TMJ) diseases are common clinical conditions. The number of patients with TMJ diseases is large, and the etiology, epidemiology, disease spectrum, and treatment of the disease remain controversial and unknown. To understand and master the current situation of the occurrence, development and prevention of TMJ diseases, as well as to identify the patterns in etiology, incidence, drug sensitivity, and prognosis is crucial for alleviating patients′suffering.This will facilitate in-depth medical research, effective disease prevention measures, and the formulation of corresponding health policies. Cohort construction and research has an irreplaceable role in precise disease prevention and significant improvement in diagnosis and treatment levels. Large-scale cohort studies are needed to explore the relationship between potential risk factors and outcomes of TMJ diseases, and to observe disease prognoses through long-term follw-ups. The consensus aims to establish a standard conceptual frame work for a cohort study on patients with TMJ disease while providing ideas for cohort data standards to this condition. TMJ disease cohort data consists of both common data standards applicable to all specific disease cohorts as well as disease-specific data standards. Common data were available for each specific disease cohort. By integrating different cohort research resources, standard problems or study variables can be unified. Long-term follow-up can be performed using consistent definitions and criteria across different projects for better core data collection. It is hoped that this consensus will be facilitate the development cohort studies of TMJ diseases.