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[Characteristics of physical therapy in diseases of the musculoskeletal system in the elderly].

Physical therapy is application of different kinds of energy for treatment. It provokes reactions by stimulation using physiological principles. Physical measures induce immediate effects as well as long-term reactions with adaptation. In diseases of the locomotor system in higher age, physical therapy is applied for diminishing pain and stiffness, amelioration of metabolism and function and especially for the maintenance of functional independence. Also fitness, good health and self-confidence can be stimulated. The age-dependent pecularities of the locomotor system, the skin and the cardiovascular system should be taken into consideration. Each method of physical treatment (hydrotherapy, heat and cold treatment, massages, exercise treatment, electrotherapy) has its age-specific peculiarities, which should be known by the treating physician. Modification of treatment can become necessary also by the kind of the disease. Dosage and technics of physical therapy must be adapted individually and supervised carefully.

Aged↗

[Tissue engineering and gene therapy of the musculoskeletal system with muscle cells].

AIM: Muscle-based somatic gene therapy is a novel way to alleviate a biochemical deficiency. METHOD: Muscle-derived cells are very promising in the field of gene therapy and tissue engineering. First, most muscle tissue is accessible by injection. Second, muscle tissue consists of multinucleated, postmitotic myofibers, which enable a long-term expression of the transduced gene. Third, muscle tissue can be biopsied easily. It is available in abundance and the biopsy does not compromise the health and function of the patient. Finally, muscle tissue is highly vascularized, which makes systemic delivery feasible. RESULTS: Muscle-derived cells can promote muscle healing and bone healing. Implanted cells maintain a long-term transgene expression of therapeutic proteins. Isolated, muscle-derived stem cells can differentiate in osteoblasts. CONCLUSION: Based on these characteristics, we present four possible applications: inherited muscular diseases, muscle injury, bone healing, and intraarticular disorders.

Gene Expression↗

Rheumatic fever and disorders of the musculoskeletal system.

New information provided on the pathogenesis and management of rheumatic fever is of current interest. Invasive disease by group A streptococci has been shown to be due to production of toxin A. The natural history and immunopathologic basis for chronic Lyme arthritis are reported. Attention is drawn to pyomyositis and clinical presentation of chronic fatigue syndrome in children. Patients with Sweet's syndrome often have antineutrophil cytoplasmic autoantibodies. Biopsy specimens of panniculitis should be taken to aid treatment. Long-term outcome in chronic osteomyelitis is favorable; recommendations on the rational use of imaging have been reported.

Child↗

Additional methods of diagnosis in the histopathology of the musculoskeletal system.

In recent years because of their diagnostic importance techniques of immunohistochemistry have been increasingly employed; The use of specific cellular antibodies has allowed for the recognition of tumors of mesenchymal, epithelial, muscular, endothelial, and neuroendocrine origin, and, within these classes, for the revelation of different cellular populations. These techniques together with histochemical and ultramicroscopic studies help define not only the genesis but also the stage of differentiation and the cell function, which are important factors in the prognosis of tumors. These have proven to be particularly useful for the differential diagnosis of highly undifferentiated forms in which cellular morphology differs from that of the tissue of origin.

Bone Neoplasms↗

Microgravity and musculoskeletal system of mammals.

This review surveys data in the literature and our own findings concerning the effects of weightlessness on bones and muscles of white rats flown on Cosmos biosatellites and Spacelab-3. It has been shown that the magnitude and sign of functional changes in muscles depend on their biomechanical profile. Structural and metabolic foundations of functional adaptation and its dynamics have been identified: in 5-7 day flights muscle contractility changes are mainly associated with a diminished activity of excitation-contraction coupling, in longer-term flights they are produced by changes in myosin populations specific for myofibers of different functional profile. At early flight stages (up to 1 week) osteoporosis and bone demineralization are very mild; therefore decrease in bone mechanical strength may be caused by changes in physico-chemical parameters of the collagen-crystal system. In flights of up to 3 weeks noticeable osteoporosis develops which is primarily produced by osteogenesis inhibition and which is responsible for a marked decrease of bone strength. These changes may result from uncoupling of bone resorption and remodelling processes. This uncoupling is characterized as incomplete osteogenesis and may be caused by changes in the collagen composition of the organic bone matrix. The above-mentioned adaptive changes in muscle functions of specific skeletal compartments may play a role in different responses of various bones to weightlessness.

Adaptation, Physiological↗

Interventional radiology and the musculoskeletal system.

Imaging-guided interventional procedures are becoming increasingly important in clinical rheumatology, since arthrocentesis of peripheral joints and the spine, as well as soft tissue injections, have a high rate of para-articular localisation when performed as blind techniques. Ultrasound-guided needle placement is the method of choice for interventional procedures on peripheral joints and for soft tissue injections. Fluoroscopy and computed tomography (CT) are not recommended for these indications due to the application of ionising radiation and the high procedural effort. By contrast, CT and magnetic resonance imaging are preferred for a variety of percutaneous procedures on the spine and sacroiliac joints. The increasing use of these methods for interventional purposes should improve both technical and procedural quality, thus ensuring cost-effectiveness and patient safety.

Humans↗

Effect of chronic centrifugation of the musculoskeletal system of the dog.

Sixteen male Beagle dogs, 293 to 509 days old, were exposed almost continuously for 3 months to 2.0 G on a 7.9 meter radius centrifuge. The dogs were maintained on the centrifuge, by means of a specially designed automated waste disposal and life support system. As compared to the mean values of normal gravity controls, centrifuged dogs showed no differences in femur length; cross-sectional area, outer and inner radii at mid-shaft of the femur; dry weights of the biceps femoris, quadriceps femoris, and gastrocnemius muscles. It was shown by analysis of covariance that chronic centrifugation has no effect on the relationship between the length and the cross-sectional dimensions at mid-shaft of the femur. Photon absorptiometry, however, revealed significant mineral content increases averaging 1.5% at 3 sites, i.e., at the 1/4, 1/2 and 3/4 length of the femur.

Animals↗

Exercise and the musculoskeletal system.

1. Normal joints in individuals of all ages may tolerate prolonged and vigorous exercise without adverse consequences or accelerated development of OA. 2. Individuals who have underlying muscle weakness or imbalance, neurological abnormalities, anatomical variances, and who engage in significant amounts of exercise that stress the lower extremities, may accelerate the development of OA. 3. Individuals who have suffered injuries to supporting structures may also be susceptible to accelerated development of OA in weight-bearing joints, even without increased stress to the joint from exercise. 4. Certain individuals with established degenerative or inflammatory arthritis may benefit from supervised exercise programmes. 5. Still more information is needed so that physicians can identify subjects at risk for the development of OA, advise the millions of participants about the beneficial and deleterious effects of regular exercise and sports participation, and develop successful rehabilitation programmes for injured joints.

Exercise↗

Magnetic resonance imaging of the musculoskeletal system. II. The hip.

Magnetic resonance (MR) imaging of the hip joint and adjacent structures can provide valuable information under many clinical circumstances. After plain radiography, MR imaging is arguably the modality of choice for the detection of osteonecrosis, occult fractures, primary and secondary neoplasms, and in the assessment of some soft tissue abnormalities. The accuracy of MR imaging is dependent on technical factors, such as magnet field strength, surface coils, and sequence selection. Low resolution MR images generally are satisfactory for screening for osteonecrosis and for the evaluation of large bone or soft tissue abnormalities. Tailoring an examination with high resolution images, specialized sequences, or contrast may add useful information, particularly if a detailed evaluation of the joint is desired. Tailoring of the examination by an experienced radiologist requires adequate clinical information, so communication between the referring physician and radiologist is crucial for optimal results. Finally, MR imaging and radiographs are complementary examinations; MR images of the hip should not be interpreted without having recent radiographs available for comparison.

Bone Neoplasms↗

Telescience testbed for biomedical experiments in space morphological and physiological experiments of rat musculoskeletal system.

As the second telescience testbed experiment we were examined sophisticated processes of biomedical experiment, such as an implantation of a transmitter into the hamster's abdominal cavity, non-stressful blood sampling, large amount of blood collection, muscle extirpation and biopsy from the hamsters on February 6-8, 1990. To make clear the differences between successful results obtained by an experienced hand and by a non-experienced one, three operators were selected for three successive experimental days; an engineer who had never experienced any biological experiment, a non-biology student, who experienced on biological experiments, and a veterinary surgeon. Surgical procedures need much experiences on maneuvering and understanding of theory to shorten the elapse time. Especially for a non-experienced hand, graphic instructions were much helpful to understand and to maneuver the procedures. Continuous recordings of ECG from a operator and PIs were of an advantage to grasp an extent of the mental strain, which was compared with their reports requested after end of each experimental day. The mental strain was not related to degrees of scientific achievement, but showed faithfully difficulty of each experimental procedure. Training effects on PIs in successive experimental days were found in their instructions for the operator to let understand the procedures.

Animals↗

Beneficial effects of regular Tai Chi exercise on musculoskeletal system.

This study was performed to evaluate the potential benefits of regular Tai Chi Chun (TCC) exercise on bone mineral density (BMD) and neuromuscular function in postmenopausal women. In this cross-sectional study, 99 healthy postmenopausal women, with a mean age of 55.9+/-3.1 years and within 10 years after the menopause, were recruited; including 48 subjects who had been regularly practicing TCC exercise for more than 3 h/week and 51 age- and sex-matched sedentary controls (CON). BMD was measured in the lumbar spine and proximal femur of the non-dominant leg (femoral neck, greater trochanter, and Ward's triangle), using dual-energy X-ray absorptiometry (DXA). Neuromuscular function was evaluated, including magnitude of trunk bend-and-reach, quadriceps muscle strength, and single-stance time on the nondominant leg. The TCC group showed overall higher BMD at all measurement sites, with a significant difference found at the spine (7.1%), greater trochanter (7.2%), and Ward's triangle (7.1%) of the proximal femur (all; P<0.05). Functional tests revealed an average 43.3% significantly greater quadriceps strength (P<0.01), and 67.8% significantly longer single-stance time in the TCC group as compared with the CON group (P<0.05), as well as a greater magnitude of trunk bend-and-reach in the TCC group (P=0.08). Bivariate linear correlation analysis showed that quadriceps muscle strength was significantly correlated with the single-stance time (r=0.41; P<0.01). This study revealed that regular TCC exercise may have an association with higher BMD and better neuromuscular function in early postmenopausal women.

Aged↗

Analysis and simulation of mechanical loads on the human musculoskeletal system: a methodological overview.

Load in the human body can be quantified as force, stress, or strain, depending on the anatomical structure and the measuring technique. Direct measurements of these variables are invasive and only possible in animals or in small-scale in vivo studies in humans. Miniaturization of transducers and electronics may open new possibilities for direct measurements of load in the human body. Studies with a large number of human subjects, and routine analysis of patients, are done using noninvasive techniques: EMG analysis for muscle forces, kinematic analysis for ligament forces, and inverse dynamics for resultant joint loads. Inverse dynamics is the most general method and is applicable to all joints in the human body. Important limitations of inverse dynamics are due to the "distribution problem": the separation of resultant loads into the individual forces in muscles and other structures. Dynamic optimization is the most promising solution method for this problem. Inverse dynamics also relies heavily on the assumption that body segments are rigid. The errors caused by this simplification are most severe in impact and vibration studies. Computer simulation is a well-established method for load analysis in mechanical engineering but is relatively rare in biomechanics. Replacing the human test subject by a mathematical model has many advantages, mainly for reproducibility and understanding of the results. Models for mechanical properties and control of muscles are an important and difficult part of computer simulation. For this reason, computer simulation has only been applied for load analysis in impact simulations, where the muscles can be regarded as passive, or for certain special problems where similarly simple muscle models can be used. In the future, we may see more applications of computer simulation for analysis of more complex activities, such as gait and sports.

Animals↗

A parameter optimization approach for the optimal control of large-scale musculoskeletal systems.

This paper describes a computational method for solving optimal control problems involving large-scale, nonlinear, dynamical systems. Central to the approach is the idea that any optimal control problem can be converted into a standard nonlinear programming problem by parameterizing each control history using a set of nodal points, which then become the variables in the resulting parameter optimization problem. A key feature of the method is that it dispenses with the need to solve the two-point, boundary-value problem derived from the necessary conditions of optimal control theory. Gradient-based methods for solving such problems do not always converge due to computational errors introduced by the highly nonlinear characteristics of the costate variables. Instead, by converting the optimal control problem into a parameter optimization problem, any number of well-developed and proven nonlinear programming algorithms can be used to compute the near-optimal control trajectories. The utility of the parameter optimization approach for solving general optimal control problems for human movement is demonstrated by applying it to a detailed optimal control model for maximum-height human jumping. The validity of the near-optimal control solution is established by comparing it to a solution of the two-point, boundary-value problem derived on the basis of a bang-bang optimal control algorithm. Quantitative comparisons between model and experiment further show that the parameter optimization solution reproduces the major features of a maximum-height, countermovement jump (i.e., trajectories of body-segmental displacements, vertical and fore-aft ground reaction forces, displacement, velocity, and acceleration of the whole-body center of mass, pattern of lower-extremity muscular activity, jump height, and total ground contact time).

Adult↗

Effect of chronic centrifugation on the structural development of the musculoskeletal system of the rat.

25 female Sprague-Dawley rats were placed on a 3.66 m radius centrifuge and subsequently exposed almost continuously for 810 days to 2.76 G. Compared to normal gravity controls, the most noticeable effect of hypergravity was the inhibition of growth of the centrifuged animals. The rats exposed to hypergravity showed on average a smaller femur length (-6.5%), a smaller cross-sectional area (-7.7%, when expressed linearly, i. e. (area/pi)1/2), and smaller outer and inner cross-sectional radii (linearly -9.3% and -12.3%) at the mid-shaft of the femoral bones. The growth inhibition of 3 hind-leg muscles was on average significantly less ranging from (-3.5% to -4.1%), compared to the growth inhibition of the linear dimension of the femur. Statistically there was no difference in the slope and elevation of the regression of the square-root of the cross-sectional area divided by pi on the length of the femur between centrifuged animals and their 16 age matched controls. In the weight control group of 24 animals, comprised of 34,74, and 102 day old rats, the corresponding regression line was parallel and lower in elevation by -12.8%, compared to the line for the centrifuged and age control groups. But, compared to the regression derived from all control animals ranging from 34 to 840 days of age, the cross-sectional area at the mid-shaft of the femur was 8.4% greater in the rats exposed to 2.76 G for 810 days. The slopes of the regression of the outer radius at mid-shaft on the length of the femur were the same in the centrifuged group and in the weight and age control groups of animals. But, the regression lines differed in elevation by -4.4% on average between the centrifuged and age control animals. The line for the regression of the inner radius at the mid-shaft on the length of the femur was parallel and lower in elevation by -7.6% in the centrifuged animals compared to the line for the age controls. But, compared to all control animals living at normal gravity, the outer radius was increased by 3.0% and the inner radius was decreased by 5.7% in the animals exposed to 2.76 G for 810 days. Since the centrifuged animals were all 840 days old, while the controls were from 34 to 840 days old, only further experiments comparing centrifuged and control animals of the same age at various growth stages will be able to furnish evidence for an unambiguous bone hypertrophy. The regressions of the cube-root of body weight on length of the femur deviate significantly in the 3 groups of animals. The heavier rats of the age control group have relatively shorter femurs than the lighter animals. The opposite applies to the centrifuged and the weight control groups of rats. Although the rats on the centrifuge are markedly smaller in overall body size than the controls, they exhibit on average the same absolute muscle weights as the animals at earth gravity, if rats of the same overall body size are compared...

Animals↗

Aging in the musculoskeletal system of rhesus monkeys: III. Bone loss.

It is well established that aging of the human skeleton includes the loss of bone mass or density, but little comparative information on age-related osteopenia in other primates is available. In order to determine whether bone loss occurs in normally locomoting nonhuman primates, radiographs of 139 rhesus monkey skeletons from the Cayo Santiago collection were examined, and measures of percent cortical bone (PCT) at the midshaft of second metacarpals, humeri, and femora were calculated. An age-related osteopenia was observed in the metacarpal of adult female macaques, although much individual variation was present. This variability could not be explained by reproductive history (number of offspring), matrilineal affiliation, or degree of osteoarthrosis. However, in a subsample of 15 animals, females who had given birth in the three months prior to death showed lower PCTs than those who had not conceived in the previous mating season. In adult males, PCT did not vary significantly with age, but males that weighed less and those with no/little osteoarthrosis showed lower PCTs than heavier or more arthritic animals, respectively. The multifactorial nature of the variation in PCT observed here suggests that similar processes of bone behavior are involved in the skeletal aging of both humans and rhesus monkeys.

Aging↗

Paralysis and growth of the musculoskeletal system in the embryonic chick.

Avian embryos can be completely paralyzed by injection of neuromuscular-blocking agents. We used a single injection of decamethonium iodide to paralyze embryos at 7, 8, or 10 days of incubation and analyzed the growth of individual bones (clavicle, mandible, ulna, femur, tibia, humerus) and of individual muscles that act upon some of those bones (clavicular and sternal heads of m. pectoralis, and mm. biceps brachii, depressor mandibulae, pseudotemporalis, and adductor externus). Growth of the bones is not equally affected by paralysis. Only 27% of clavicular growth (by mass) but 77% of mandibular growth occurred in paralyzed embryos, whereas the four long bones exhibited 52-63% of their normal growth. Analysis of muscle weight, fiber length and physiological cross-sectional area (weight/fiber length) indicate that there was greater reduction of the muscles acting on the limbs than of those acting on the mandible, i.e., diminished growth of the skeleton is correlated with reduced muscular activity. Specific retardation of clavicular growth is due to fusion of sternal rudiments and collapse of the thorax, as well as virtual absence of the musculature that normally attaches to the clavicle. We discuss these results in the light of intrinsic and extrinsic factors governing growth of the embryonic skeleton. Paralysis reduces skeletal growth by reducing both the movements taking place in ovo, and the loads imposed on the bones by muscle contraction, changes that represent alterations in the mechanical environment of the skeleton.

Animals↗