No abstract available.
Animal ; Bone and Bones/blood supply* ; Bone and Bones/innervation ; Bone and Bones/physiology ; Comparative Study ; Dogs ; Human ; Joints/blood supply* ; Joints/innervation ; Joints/physiology ; Muscle Contraction ; Oxygen Consumption ; Rabbits ; Rats

This paper introduces the hardware and software of a biomechanical robot-based testing device. The bottom control orders, posture and torque data transmission, and the control algorithms are integrated in a unified visual control platform by Visual C+ +, with easy control and management. By using hybrid force-displacement control method to load the human spine, we can test the organizational structure and the force state of the FSU (Functional spinal unit) well, which overcomes the shortcomings due to the separation of the force and displacement measurement, thus greatly improves the measurement accuracy. Also it is esay to identify the spinal degeneration and the load-bearing impact on the organizational structure of the FSU after various types of surgery.
Algorithms ; Biomechanical Phenomena ; Equipment Design ; Humans ; Joints ; physiology ; Robotics ; instrumentation ; methods ; Software ; Spine ; physiology

The present study was aimed at the optimal solution of the main muscular force distribution in the lower extremity during standing balance of human. The movement musculoskeletal system of lower extremity was simplified to a physical model with 3 joints and 9 muscles. Then on the basis of this model, an optimum mathematical model was built up to solve the problem of redundant muscle forces. Particle swarm optimization (PSO) algorithm is used to calculate the single objective and multi-objective problem respectively. The numerical results indicated that the multi-objective optimization could be more reasonable to obtain the distribution and variation of the 9 muscular forces. Finally, the coordination of each muscle group during maintaining standing balance under the passive movement was qualitatively analyzed using the simulation results obtained.
Algorithms ; Gait ; Humans ; Joints ; Models, Biological ; Models, Theoretical ; Movement ; Muscles ; physiology ; Postural Balance

The scaling method of the loss degree of joint motion is very common in clinical forensic medicine. However, there is no uniform criterion until now. Therefore, this had made a negative effect to ensure the impartiality and justice in law and the identification. The advantages and disadvantages of the four methods recorded in literatures by practical case, which include major and minor methods, additional methods, directive average methods, axial directive average methods, were discussed and compared. Now three basic critics about how to choosing the applicable technique in forensic medicine were supposed according to the impartiality and justice principle, scientific and objective principle, simple and easy principle. It was hoped that we can reach a consensus in our legal-medical circumscription that all of us can choose the Axial Directive Average Methods as our standard for the loss degree of joint motion, to avoid the disadvantages of this aspect.
Adult ; Forensic Medicine/methods* ; Humans ; Joints/injuries* ; Male ; Range of Motion, Articular/physiology* ; Wrist Injuries/physiopathology*

The development process of joint kinematics and kinetics is expatiated from the aspects of technology and method. Firstly, the classical mechanics-based methods are introduced. Secondly, the computer assisted methods are analyzed from the technical aspects of video tracking, fluoroscopy and MR imaging separately. Then the assistance of robotic technique in this field is discussed. Finally the potential trend in the joint kinematics and kinetics is concluded.
Biomechanical Phenomena ; Computer Simulation ; Humans ; Image Interpretation, Computer-Assisted ; methods ; Joints ; physiology ; Magnetic Resonance Imaging ; Movement ; physiology ; Range of Motion, Articular ; physiology

OBJECTIVETo assess the amount of sound transmission loss in order to deeply understand the mechanism of middle ear sound transmission for ossicular reconstruction and for guidance of crimping between prosthesis and stapes on sound transmission in stapes surgery.

METHODSIn order to get a correcting magnetic field 2 temporal bone models was used first. Temporal bone models was developed using 17 human temporal bones from fresh cadavers. To measure the sound transmission properties in the middle ear, 15 temporal bone models were detected by scanning laser Doppler interferometry with acoustical stimulation and electromechanical stimulation. An algorithm was developed to simulate acoustical stimulation with electromechanical stimulation. A sound transmission loss within the incudostapedial joint was detected by electromechanical stimulation in 10 temporal bone models.

RESULTSThe average transmission loss within the incudostapedial joint remained 3 dB over the frequencies detected.

CONCLUSIONSThere was a sound transmission loss within the incudostapedial joint, which was a physiological and protection way.

Acoustic Stimulation ; Aged ; Aged, 80 and over ; Algorithms ; Ear, Middle ; physiology ; Female ; Humans ; Joints ; physiology ; Male ; Middle Aged ; Models, Biological ; Sound ; Temporal Bone ; physiology

OBJECTIVETo measure the changes of plantar pressure of the first tarsometatarsal joint fracture and dislocation by three different implants to provide experimental reference in selecting implants.

METHODSEight fresh foot specimens were made into the models of the first tarsometatarsal joint fracture and dislocation, which were fixed with 3.5 mm cortical screw, 1/4 tubular plate and compressive staple in turn. After the loading of 600 N, the changes of the plantar pressure in forefoot were measured by the method of the F-scan plantar pressure system.

RESULTSAfter first tarsometatarsal joint fracture and dislocation, the peak pressure under the first metatarsal head would decrease, while the pressure under the second metatarsal head would increased,whose differences were statistically significant (P<0.05). When the first tarsometatarsal joint was fixed with screw or plate respectively; the peak pressure under the two metatarsal heads would tend to be normal. However,the staple fixation showed the statistical significant difference compared with normal state, although the peak pressure under the first and second metatarsal heads were recovered in some extent(P<0.05).

CONCLUSIONAfter the first tarsometatarsal joint fracture-dislocation, the plantar pressure might be compensated partly by the adjacent metatarsal heads according to the regulation of the load transfer mechanism. While the first tarsometatarsal joint fracture-dislocation was fixated by screw or plate, the plantar pressure of the forefoot would return to the normal state. However,if the joint was fixated by the staple, it would still be difficult to return the plantar pressure to be normal.

Foot Joints ; injuries ; surgery ; Forefoot, Human ; physiology ; Fracture Fixation, Internal ; methods ; Fractures, Bone ; surgery ; Humans ; Joint Dislocations ; surgery ; Pressure

The synovial membrane of the temporomandibular joint lines all the intraarticular structures except the articular cartilage of the articular eminence, fossa, the mandibular condyle and the articular disc. The synovial membrane consists of two layers. The first layer is a lining cell layer facing the joint space and called synovial intima. The second layer is called subintimal or subsynovial tissue. The synovial membrane fulfills several important functions in maintaining normal joint physiology and joint function. Synovitis occurs when the level of cellular debris and the concentration of chemical mediators of inflammation produce levels that the synovial membrane is unable to ingest, absorb or process. So degeneration of temporomandibular joint may be increased by deficiency of synovial fluid. After general anesthesia by intramuscular injection of ketamin, exposure of TMJ of rabbit was done by preauricular approach. After exposure, rubber drain was inserted into the upper joint cavity, to prevent accumulation of synovial fluid. Penicillin G was used to prevent secondary infection for 3 days. Fifteen Rabbits were used for experiment, and subdivided into 5 groups (one normal group and 4 experimental groups, each subdivided group consisted in 3 rabbits). Experimental groups were taken after period of 1, 2, 3, 4 weeks. After euthansia, enbloc excision of TMJ was done to make biopsy specimen. The results were as follows; 1. Layers of synovial intima were increased in experimental group, 8~10 layers in first week group and 4~5 layers in fourth week group as compared with 2~3 layers in normal group. 2. Inflammation, vascular change and subintimal edema were highest in second week group, but continued to fourth week group. 3. Subintimal fibrosis occured in second week group, and increased to fourth week group. 4. Due to fibrosis of joint cavity, narrowing of joint space occured in the third week group, and increased to fourth week group. 5. Degeneration of articular disc occured in second week group and increased to fourth week group.
Anesthesia, General ; Biopsy ; Cartilage, Articular ; Coinfection ; Edema ; Fibrosis ; Inflammation ; Inflammation Mediators ; Injections, Intramuscular ; Joints* ; Mandibular Condyle ; Penicillin G ; Physiology ; Rabbits* ; Rubber ; Synovial Fluid* ; Synovial Membrane ; Synovitis ; Temporomandibular Joint

The purpose of this study was to evaluate how soft tissue surgery for correcting equinus deformity affects the kinematic and kinetic parameters of the ankle and proximal joints. Sixteen children with spastic hemiplegic cerebral palsy and equinus deformities (age range 3-16 years) were included. Soft tissue surgeries were performed exclusively on the ankle joint area in all subjects. Using computerized gait analysis (Vicon 370 Motion Analysis System), the kinematic and kinetic parameters during barefoot ambulation were collected preoperatively and postoperatively. In all 16 children, the abnormally increased ankle plantar flexion and pelvis anterior tilting on the sagittal plane were significantly improved without a weakening of push-off (p < 0.05). In a group of 8 subjects with a recurvatum knee gait pattern before operation, the postoperative kinematic and kinetic parameters of the knee joint were significantly improved (p < 0.05). In a group of 8 subjects with ipsilateral pelvic external rotation before operation, the postoperative pelvic deviations on the transverse plane were significantly decreased (p < 0.05). These findings suggest that the soft tissue surgery for correcting equinus deformity improves not only the abnormal gait pattern of the ankle, but also that of the knee and pelvis.
Male ; Kinetics ; Joints/physiopathology/surgery ; Humans ; Hemiplegia/*surgery ; Gait/physiology ; Female ; Equinus Deformity/*surgery ; Child, Preschool ; Child ; Cerebral Palsy/*surgery ; Biomechanics ; Ankle Joint/physiopathology/surgery ; Adolescent

Fractures in children differ from those in adults. Because the anatomy, biomechanics, and physiology of a child's skeleton very differ from those of an adult, orthopedic surgeons frequently see differences in the pattern of fractures, the problems of diagnosis, and the method of treatment. So the present study is an clinical analysis of 622 cases of children's fractures under the age of 18 years, who were treated at the department of orthopedic surgery, Presbyterian Medical Center for the past 9 years from 1973 to 1981. Results obtained are as follows: 1. The peak age was 5. 2. The incidence in male was 2 times higher than in female. 3. The most common cause of fractures was traffic accident (65.6% of all cases). 4. The fracture in femur was most common (17.7%). 5. The most common injury combined with fracture was head injury (40.3%). 6. Among the joints elbow was most commonly injuried. 7. The incidence of epiphyseal injury was 10.3%. 8. The most common type of epiphyseal injury by Salter & Harris classification was type II and it's incidence was 57.8% of all epiphyseal injury. 9. 83% of all fractures were conservatively treated. 10. The incidence of complication of all cases was 8.5%.
Accidents, Traffic ; Adult ; Child ; Classification ; Clinical Study ; Craniocerebral Trauma ; Diagnosis ; Elbow ; Female ; Femur ; Humans ; Incidence ; Joints ; Male ; Methods ; Orthopedics ; Physiology ; Protestantism ; Skeleton ; Surgeons