The clinical treatment of joint contracture due to immobilization remains difficult. The pathological changes of muscle tissue caused by immobilization-induced joint contracture include disuse skeletal muscle atrophy and skeletal muscle tissue fibrosis. The proteolytic pathways involved in disuse muscle atrophy include the ubiquitin-proteasome-dependent pathway, caspase system pathway, matrix metalloproteinase pathway, Ca-dependent pathway and autophagy-lysosomal pathway. The important biological processes involved in skeletal muscle fibrosis include intermuscular connective tissue thickening caused by transforming growth factor-β1 and an anaerobic environment within the skeletal muscle leading to the induction of hypoxia-inducible factor-1α. This article reviews the progress made in understanding the pathological processes involved in immobilization-induced muscle contracture and the currently available treatments. Understanding the mechanisms involved in immobilization-induced contracture of muscle tissue should facilitate the development of more effective treatment measures for the different mechanisms in the future.
Atrophy ; Autophagy ; Calcium ; metabolism ; Caspases ; metabolism ; Connective Tissue ; metabolism ; pathology ; Contracture ; etiology ; metabolism ; pathology ; therapy ; Fibrosis ; Humans ; Immobilization ; adverse effects ; Joints ; Lysosomes ; metabolism ; Matrix Metalloproteinases ; metabolism ; Muscle, Skeletal ; metabolism ; pathology ; Proteasome Endopeptidase Complex ; metabolism ; Proteolysis ; Signal Transduction ; physiology ; Transforming Growth Factor beta1 ; metabolism ; Ubiquitin ; metabolism

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 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

Isokinetic technology in testing and training is the most advanced practical technique in the evaluation of muscle function. This method is a continuous dynamic test in the full range of the joint motion which has strong pertinence at the aspect of assessing muscle strength, and is an objective and quantitative method for reflecting each point's muscle strength in the range of the joint motion. This article reviews the key concepts, brief history of development and influencing factors of isokinetic technology in testing and training, introduces the progress in the field of rehabilitation medicine and sport science, etc., and discusses the future exploration in forensic science.
Biomechanical Phenomena ; Forensic Medicine/methods* ; Humans ; Isometric Contraction/physiology* ; Joints/physiopathology* ; Muscle Contraction/physiology* ; Muscle Strength/physiology* ; Muscle Strength Dynamometer ; Muscle, Skeletal/physiopathology* ; Physical Education and Training/methods* ; Physical Exertion ; Physical and Rehabilitation Medicine ; Posture ; Range of Motion, Articular/physiology* ; Sports Medicine ; Wounds and Injuries/rehabilitation*

IL-17-producing CD4+ T cells (Th17) play important functions in autoimmune diseases and allograft rejection of solid organs. We examined the effects of IL 17 and its mechanism of action on arthritis in a murine collagen-induced arthritis (CIA) model using bone marrow transplantation (BMT) system. DBA/1J mice were administered a lethal radiation dose and then rescued with bone marrow derived from either wild-type (WT) or IL-17-/- mice on C57BL/6 background mice. CIA was induced after the bone marrow transplant, and disease progression was characterized. DBA/1J mice with CIA that received IL-17-/- donor bone marrow showed potently inhibited development and severity of clinical arthritis as compared with CIA mice that received WT bone marrow. Reduced secretion of the pro-inflammatory cytokines tumor necrosis factor-alpha, IL-1beta, and IL-6, and collagen-specific T cell responses were observed in mice that received IL-17-/- bone marrow. IL-17 blockade also inhibited effector T cell proliferation by reciprocally regulating the Treg/Th17 ratio. IL-17 blockade prevented joint destruction in mice with CIA. These findings suggest that CIA with BMT is a viable method of immunological manipulation and that IL-17 deficiency suppresses severe joint destruction and inflammation in CIA mice. There may be clinical benefits in blocking IL-17 and BMT in the treatment of rheumatoid arthritis.
Animals ; Antigens, Differentiation/metabolism ; Arthritis, Experimental/pathology/*prevention & control ; *Bone Marrow Transplantation ; Cell Differentiation ; Cell Proliferation ; Cells, Cultured ; Collagen Type II ; Cytokines/metabolism ; Humans ; Interleukin-17/*deficiency/genetics ; Joints/pathology ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Inbred DBA ; Mice, Knockout ; Osteoclasts/metabolism/physiology ; Signal Transduction ; T-Lymphocytes/metabolism/physiology ; Transplantation, Homologous

OBJECTIVE: To further improve the accuracy of bone age identification using the time of secondary ossification center appearance and epiphyseal fusion of 7 joints to estimate the age of living individuals. METHODS: DR films were taken from 7 parts including sternal end of clavical and the left side of shoulder, elbow, carpal, hip, knee and ankle joints of 1 709 individuals who came from eastern China, central China and southern China, whose ages were between 11.0 and 20.0 years. From those 7 joints 24 osteal loci were selected as bone age indexes, which could better reflect age growth of teenagers. The characteristics of secondary ossification center appearance and epiphyseal fusion were observed, and the mean and age range of secondary ossification center appearance and epiphyseal fusion were calculated. RESULTS: The fusion time of the 24 epiphyses were advanced at different degrees, the most obvious epiphyses the sternal end of clavicle, scapular acromial end, distal end of the radius, distal end of the ulna, iliac crest, ischial tuberosity, the upper and lower end of tibia and fibula. The appearance time of sternal end of clavicle, scapular acromial end, iliac crest and ischial tuberosity epiphyses were all found to be after the age of 12, and the female's age, approximately 1 year ahead of schedule in comparison with the male's. CONCLUSION The relevant forensic information and data for bone age identification should be updated every 10-15 years so as to provide accurate and objective evidence for court testimony, conviction and sentencing.
Adolescent ; Age Determination by Skeleton/methods* ; Asian People/ethnology* ; Bone Development/physiology* ; Bone and Bones/diagnostic imaging* ; Child ; China/ethnology* ; Clavicle/growth & development* ; Epiphyses/growth & development* ; Female ; Forensic Anthropology/methods* ; Humans ; Joints/growth & development* ; Male ; Sex Characteristics ; Tomography, X-Ray Computed ; Young Adult

The aim of present study was to investigate the effect of chronic intermittent hypobaric hypoxia (CIHH) on collagen-induced arthritis (CIA) in rat. Fifty male adult Sprague-Dawley rats were randomly divided into 5 groups: CIHH pre-treatment group (Pre-T), pre-control group (Pre-C), CIHH post-treatment group (Post-T), post-control group (Post-C) and blank control group (Con). The rats in Pre-T and Post-T groups were exposed to 28 d of hypobaric hypoxia (simulated 3 000 m altitude, 5 h per day, pO2 = 108.8 mmHg, 14% O2) in a hypobaric chamber before and 12 days after CIA induction, respectively. The rats in Pre-C and Post-C groups were only experienced CIA induction, being control groups for Pre-T and Post-T groups, respectively. The rats in Con group were not given any treatment. The thickness of two-hind paw of rat was measured with spiral micrometer and the degree of arthritis was evaluated by arthritis index (AI). Morphological changes of ankle joint were observed through HE staining. The apoptotic rate in synovial tissue was measured by terminal dUTP nick end labeling (TUNEL) and the apoptotic rate of CD3(+) T lymphocyte in spleen was measured by flow cytometry technique. The protein expressions of Bcl-2 and Bax were measured using immunohistochemistry SP method. The results showed that incidence rate of CIA in Pre-T rats was lower than that in Pre-C rats (P < 0.05). AI in Pre-T and Post-T rats were smaller than those in Pre-C and Post-C, respectively (P < 0.05). In Pre-C and Post-C rats, there were hyperplasia of synovial cell, pannus forming, infiltration with inflammatory cell, and destroyed cartilage and bone in ankle joint. On the contrary, pathological changes of ankle joint were alleviated significantly in Pre-T and Post-T rats. Compared with Pre-C and Post-C rats, apoptotic rates of synovial cell and T lymphocyte in Pre-T and Post-T rats were increased (P < 0.05). As to the possible anti-apoptosis mechanism, CIHH, no matter before and after CIA induction, decreased Bcl-2 expression and increased Bax expression in joint synovial cells and spleen T lymphocytes (P < 0.05), respectively. In conclusion, CIHH possesses a protective effect against CIA in rat by enhancing apoptosis of synovial cells and T lymphocytes, which may be related to the inhibition of Bcl-2 protein expression and the promotion of Bax protein expression.
Animals ; Apoptosis ; physiology ; Arthritis, Experimental ; pathology ; physiopathology ; prevention & control ; Hypoxia ; physiopathology ; Ischemic Postconditioning ; methods ; Ischemic Preconditioning ; methods ; Joints ; pathology ; Male ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Rats ; Rats, Sprague-Dawley ; Spleen ; cytology ; Synovial Membrane ; pathology ; T-Lymphocytes ; pathology ; bcl-2-Associated X Protein

OBJECTIVE: To analyze and compare different methods for assessment of the limbs joints function and to discuss the rationality of the methods. METHODS: Eight hundred and six cases were collected from the Fujian Minzhong Forensic Appraisal Center from 2007 to 2010. These cases included injuries of large limbs joints with or without peripheral nerve injury. The loss of joint function was calculated according to the simple joint mobility method or the table method introduced in the book "Forensic Clinical Judicial Authentication Practice". The results of disability evaluation with different methods were analyzed and compared between different joints and injury patterns. RESULTS: In 642 cases of simple joint injuries without peripheral nerve injury, the results of disability evaluation based on simple joint mobility were the same as that based on the table. In 118 cases of joint injuries with peripheral nerve injury, all of them could be classified as disability, 33 cases (28.00%) had higher degree based on the table method than based on the simple joint mobility method. While 21 cases (17.80%) did not be evaluated as disabled based on the simple joint mobility method. CONCLUSION The evaluation for loss of limb function would be easier, more scientific and reasonable by the direct table method than the simple joint mobility method.
Accidents, Traffic ; Adult ; Arm Injuries/physiopathology* ; Disability Evaluation ; Extremities ; Female ; Forensic Medicine/methods* ; Humans ; Joints/physiopathology* ; Leg Injuries/physiopathology* ; Male ; Peripheral Nerve Injuries/physiopathology* ; Range of Motion, Articular/physiology* ; Trauma Severity Indices

OBJECTIVE: To study the difference of Han female adolescent bone development in Henan and Zhejiang province. METHODS: All radiography including sternal end of clavicle and six main bone joints were taken from 599 female adolescents with age between 12 to 19 in Henan and Zhejiang province. Twenty four skeletal development indexes were analyzed based on "The Grading Standards" of skeletal growth of teenagers and then the bone age were calculated using mathematical model functions. The ratios of the bone age and the chronological age were analyzed by statistical software. RESULTS: The development of Henan female adolescents' skeleton was about 0.39 years earlier than that in Zhejiang at the age of 14-15 years old. The development of Henan female adolescents' skeleton was about 0.37 years later than that in Zhejiang at the age of 15-16 years old. The development of Henan female adolescents' skeleton was about 0.38 years later than that in Zhejiang at the age of 18-19 years old. There was no statistics significance in other age group. CONCLUSION The female adolescent bone development in Henan province is faster at earlier stage and then slower than that in Zhejiang province. The results provide potential value for the forensic medicine, anthropology and clinical medicine.
Adolescent ; Age Determination by Skeleton/methods* ; Age Factors ; Analysis of Variance ; Bone Development/physiology* ; Child ; China/ethnology* ; Clavicle/diagnostic imaging* ; Epiphyses/physiology* ; Female ; Forensic Anthropology/methods* ; Humans ; Joints/physiology* ; Models, Theoretical ; Sampling Studies ; Sternum/diagnostic imaging* ; Tomography Scanners, X-Ray Computed ; Young Adult

Osteoarthritis (OA) is a chronic joint disease that involves degeneration of articular cartilage, limited intra-articular inflammation manifested by synovitis and changes in the subchondral bone. After the articular cartilage's stability and complex structure in the framework of pressure-proof were destruct, the ability to repair by itself was weak. Therefore early diagnosis in the treatment of osteoarthritis is a focal ponit. This paper addressed on the characteristics of diagnosis of OA in the relevant objective diagnostic methods.
Adult ; Aged ; Bone Density ; physiology ; Bone and Bones ; diagnostic imaging ; pathology ; Calcification, Physiologic ; Cartilage, Articular ; diagnostic imaging ; pathology ; Female ; Humans ; Joints ; diagnostic imaging ; pathology ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Osteoarthritis ; diagnosis ; epidemiology ; Osteoarthritis, Knee ; diagnosis ; diagnostic imaging ; Radiography ; Radionuclide Imaging ; Synovial Membrane ; diagnostic imaging ; pathology ; Ultrasonography