Objective To study the blood_flow_activating and blood_stasis_removi ng actions of Qushang Tablet (QT) and its safety. Methods Thirty rats were randomly allocated to Group A (normal control), Group B (models control) and G r oup C (treated with QT). Rat models with traumatic blood_stasis syndrome were in duc ed by the bruise of falling iron hammer. Effects of QT on blood rheology of rat model were studied. Acute and chronic toxic effect of QT was also studied. Res ults QT had obvious effect on blood rheology of rat model and could improve th e concentration, viscosity, aggregation and coagulability of blood. No acute and chronic toxic effect of QT was found. Conclusion QT exerts obvious blood_fl ow_activating and blood_stasis_removing actions and is safe to be applied in cli nic.

Objective To evaluate the short term results of repairing osteonecrosis of the femoral head by modified free vascularized fibular grafting through Smith-Peterson approach without cutting the rectus femoris.Methods Between January,2009 and September,2012,14 osteonecrotic hips of 14 patients who underwent free vascularized fibular grafting were retrospectively studied including 10 male and 4 female.The follow up period was 24 months.The preoperative and postoperative symptoms relief,recovery of hip function (Harris score),radiographic assessment (X-ray).Results All patients got postoperative ipsilateral hip pain relief.Average Harris hip score improved significantly (68.47 ± 5.33,86.80 ± 4.72 points in preoperation and postoperation,respectively; paired t test,t =18.724,P ＜ 0.01).Postoperative X-ray results showed there were no progresses of osteonecrosis and no collapse in the operative side within 2 years follow-up.Conclusion The short term treatment results of femoral head avascular necrosis were satisfactory by using free vascularized fibular graft through Smith-Peterson approach without cutting off the rectus femoris and it may be a relatively practical option of surgical approach.

Objective To investigate the effect and safety of comprehensive therapy based on femoral head arthroplasty in treating old femoral neck fracture in the elderly complicated with other severe basic medical conditions.Methods Thirty-six elderly patients with old femoral neck fracture were treated with femoral head arthroplasty.Mean age of the patients was 78.2 years, and mean duration since injury was 13.7 months.All the patients had at least one severe basic medical problem.Perioperative complications were retrospectively analyzed, and function of hip joint was evaluated 6 months after operation.Results One patient died because of severe pulmonary infection, while 16 electrolyte imbalance, 7 hypotension, 4 arrhythmia, 2 acute heart failure and 1 acute kidney injury were cured in the rest 35 patients.Harris hip score of the 35 patients increased from (22.0 ± 6.8) points pre-operatively to (69.2 ± 10.8) points 6 months post-operatively (P ＜ 0.01).Conclusions Comprehensive therapy based on femoral head arthroplasty is effective for old femoral neck fracture in the elderly suffering severe underlying diseases.Early treatment, perfect pre-operative preparation, correct manipulation and appropriate perioperative management play important roles.

Osteoarthritis are usual disease in middle aged and elderly people. High tibial osteotomy is a common method which performed to treat medial compartment osteoarthritis in varus knees. Unicondylar knee arthroplasty is an established treatment option for symptomatic osteoarthritis isolated to one compartment, and received remarkably effect. Total knee arthroplasty is the standard treatment of serious knee disease. The knee kinematics have changed after the knee was diseased, and the kinematics after surgery are different from the natural joint. The flexion-extension rotation, anterior-posterior translation and interior-exterior rotation are most important kinematics of tibia-femur joint. The anterior-posterior translation and interior-exterior rotation, which as the secondary kinematics, even are paradoxical after total knee arthroplasty. Secondary kinematics studies played an important role in prosthesis design and postoperative functional assessment. Measurement and description methods of knee joint secondary kinematics were reviewed in this article. The factors influencing secondary kinematics were investigated for natural knee joint, osteoarthritis knee joint and knee joint after total knee replacement separately, and the influence of total knee replacement design was emphasized. At last, the impact of knee secondary kinematics to biomechanics, friction and wear were also introduced. After comparison of multi-research results, the measurement precision was found to need further improvement due to the restrict of measuring technology and description methods. Many factors influence knee secondary kinematics, including activities, measurement environment and individual difference. The anterior-posterior translation was found complex after total knee replacement, and the prosthesis design played an important role. Posterior cruciate ligament-retaining knee replacement lead forward slide of the femoral component during flexion, which paradoxical from natural knee. The anatomical design prosthesis were hopeful to realize more natural kinematics. The component malalignment and soft tissue balance during surgey also have significant role in knee secondary kinematics. The knee secondary kinematics study is of great significance to biomechanics and wear.

A micro silicone oil liquid spring was designed and manufactured in this article. The performance of the liquid spring was studied by simulation analysis and mechanical test. A self-force source power-assisted knee orthosis was designed based on the liquid spring. This power-assisted knee orthosis can convert the kinetic energy of knee flexion into the elastic potential energy of liquid spring for storage, and release elastic potential energy to generate assisted torque which drives the knee joint for extension. The results showed that the average maximum reset force of the liquid spring was 1 240 N, and the average maximum assisted torque for the knee joint was 29.8 N·m. A musculoskeletal multibody dynamic model was used to analyze the biomechanical effect of the knee orthosis on the joint during knee bending (90°knee flexion). The results showed that the power-assisted knee orthosis could effectively reduce the biomechanical load of the knee joint for the user with a body weight of 80 kg. The maximum forces of the femoral-tibial joint force, patellar-femoral joint force, and quadriceps-ligament force were reduced by 24.5%, 23.8%, and 21.2%, respectively. The power-assisted knee orthosis designed in this article provides sufficient assisted torque for the knee joint. It lays a foundation for the subsequent commercial application due to its small size and lightweight.
Biomechanical Phenomena ; Knee Joint ; Femur ; Ligaments ; Orthotic Devices

The clinical performance and failure issues are significantly influenced by prosthetic malposition in unicompartmental knee arthroplasty (UKA). Uncertainty exists about the impact of the prosthetic joint line height in UKA on tibial insert wear. In this study, we combined the UKA musculoskeletal multibody dynamics model, finite element model and wear model to investigate the effects of seven joint line height cases of fixed UKA implant on postoperative insert contact mechanics, cumulative sliding distance, linear wear depth and volumetric wear. As the elevation of the joint line height in UKA, the medial contact force and the joint anterior-posterior translation during swing phase were increased, and further the maximum von Mises stress, contact stress, linear wear depth, cumulative sliding distance, and the volumetric wear also were increased. Furthermore, the wear area of the insert gradually shifted from the middle region to the rear. Compared to 0 mm joint line height, the maximum linear wear depth and volumetric wear were decreased by 7.9% and 6.8% at -2 mm joint line height, and by 23.7% and 20.6% at -6 mm joint line height, the maximum linear wear depth and volumetric wear increased by 10.7% and 5.9% at +2 mm joint line height, and by 24.1% and 35.7% at +6 mm joint line height, respectively. UKA prosthetic joint line installation errors can significantly affect the wear life of the polyethylene inserted articular surfaces. Therefore, it is conservatively recommended that clinicians limit intraoperative UKA joint line height errors to -2-+2 mm.
Humans ; Arthroplasty, Replacement, Knee ; Knee Joint ; Knee Prosthesis ; Mechanical Phenomena ; Polyethylene ; Osteoarthritis, Knee/surgery* ; Tibia/surgery* ; Biomechanical Phenomena

The simulation of excitation propagation's process in human heart is one of the main aspects of ECG forward problem. The simulation results not only are the criterion of the simulation model's precision and reliability, but also have great value in researches and diagnoses. We performed the simulation of QRST waves of complete left bundle branch block (LBBB) and right bundle branch block (RBBB) in virtue of a vector propagation algorithm (VPA), which is accurate, efficient and applicable to anisotropic computer heart models. The simulation results accord with the actual QRST wave in clinical practice.
Algorithms ; Bundle-Branch Block ; pathology ; Computer Simulation ; Electrocardiography ; Humans ; Models, Cardiovascular ; Reproducibility of Results

Posterior-stabilized total knee prostheses have been widely used in orthopedic clinical treatment of knee osteoarthritis, but the patients and surgeons are still troubled by the complications, for example severe wear and fracture of the post, as well as prosthetic loosening. Understanding the in vivo biomechanics of knee prostheses will aid in the decrease of postoperative prosthetic revision and patient dissatisfaction. Therefore, six different designs of posterior-stabilized total knee prostheses were used to establish the musculoskeletal multibody dynamics models of total knee arthroplasty respectively, and the biomechanical differences of six posterior-stabilized total knee prostheses were investigated under three simulated physiological activities: walking, right turn and squatting. The results showed that the post contact forces of PFC Sigma and Scorpio NGR prostheses were larger during walking, turning right, and squatting, which may increase the risk of the fracture and wear as well as the early loosening. The post design of Gemini SL prosthesis was more conductive to the knee internal-external rotation and avoided the edge contact and wear. The lower conformity design in sagittal plane and the later post-cam engagement resulted in the larger anterior-posterior translation. This study provides a theoretical support for guiding surgeon selection, improving posterior-stabilized prosthetic design and reducing the prosthetic failure.
Arthroplasty, Replacement, Knee/methods* ; Biomechanical Phenomena ; Humans ; Knee Joint/surgery* ; Knee Prosthesis ; Prosthesis Design ; Range of Motion, Articular/physiology* ; Tibia/surgery*

The surgical installation accuracy of the components in unicompartmental knee arthroplasty (UKA) is an important factor affecting the joint function and the implant life. Taking the ratio of the medial-lateral position of the femoral component relative to the tibial insert (a/A) as a parameter, and considering nine installation conditions of the femoral component, this study established the musculoskeletal multibody dynamics models of UKA to simulate the patients' walking gait, and investigated the influences of the medial-lateral installation positions of the femoral component in UKA on the contact force, joint motion and ligament force of the knee joint. The results showed that, with the increase of a/A ratio, the medial contact force of the UKA implant was decreased and the lateral contact force of the cartilage was increased; the varus rotation, external rotation and posterior translation of the knee joint were increased; and the anterior cruciate ligament force, posterior cruciate ligament force and medial collateral ligament force were decreased. The medial-lateral installation positions of the femoral component in UKA had little effect on knee flexion-extension movement and lateral collateral ligament force. When the a/A ratio was less than or equalled to 0.375, the femoral component collided with the tibia. In order to prevent the overload on the medial implant and lateral cartilage, the excessive ligament force, and the collision between the femoral component and the tibia, it is suggested that the a/A ratio should be controlled within the range of 0.427-0.688 when the femoral component is installed in UKA. This study provides a reference for the accurate installation of the femoral component in UKA.
Humans ; Arthroplasty, Replacement, Knee ; Knee Joint/surgery* ; Knee Prosthesis ; Gait ; Rotation

OBJECTIVETo study the chemical constituents of Halenia elliptica.

METHODThe air-dried whole plants of Halenia elliptica were extracted with 90% EtOH. The EtOH extract was condensed to a small amount of volume and extracted with petroleum ether, EtOAc and n-BuOH, successively. The compounds were isolated and purified by column chromatography from the EtOAc fraction, and identified based on spectral analyses (MS, 1H-NMR, 13C-NMR).

RESULT12 compounds were isolated from H. elliptica, and characterized as 8-hydroxy-2-methylchromone (1), 5-methoxy-2-methylchromone (2), 7-epi-vogeloside (3), coniferl aldehyde (4), sinapaldehyde (5), norbellidifolin (6), 1-hydroxyl-2,3,4,6-tetramethoxyxanthone (7), 1-hydroxyl-2,3,4,7-tetramethoxyxanthone (8), 1-hydroxyl-2,3,5-trimethoxyxanthone (9), together with azelaic acid, beta-sitosterol, and oleanolic acid.

CONCLUSIONCompounds 1, 2 were new natural compounds and compounds 3-6, 10 were obtained from H. elliptica for the first time and compound 6 showed inhibitory activities against HBsAg and HBeAg secretion with IC50 value of 0.77 and < 0.62 mmol x L(-1), respectively.

Acrolein ; analogs & derivatives ; analysis ; isolation & purification ; Chromatography ; Dicarboxylic Acids ; analysis ; isolation & purification ; Gentianaceae ; chemistry ; Iridoid Glycosides ; isolation & purification ; Magnetic Resonance Spectroscopy ; Mass Spectrometry ; Oleanolic Acid ; analysis ; isolation & purification ; Plant Extracts ; isolation & purification ; Sitosterols ; analysis ; isolation & purification ; Xanthones ; analysis ; isolation & purification