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PubMed1979

[The effect of calcitonin on contractile function of skeletal muscles (author's transl)].

The analgesic effect of calcitonin in osteoporosis has been considered to originate from its actions on bone metabolism. However, the author assumed a possible presence of other mechanism, since the analgesic effect of calcitonin manifests in an extremely early phase in which an increase in bone mass is hardly conceivable. Namely, the author postulated that its analgesic effect is due to its actions on body trunk muscles, and investigated experimentally the effect of calcitonin on skeletal muscles. The following results were obtained. 1) Recovery from decreased twitch contraction of M. triceps surae was shown in vivo in rats treated with calcitonin, with dose-response relationship. 2) Calcitonin exerted no effect on partial blockade by dTc, in neuro-muscular junction. Therefore, the neuro-muscular junction is probably not the site of the actions of calcitonin. 3. In an in vitro study on isolated M. soleus, the decrease contraction was recovered after treatment with calcitonin. A correlation was found between this recovery and the dose of calcitonin. 4) In the calcitonin treated muscle, a pronounced persistence of normal contraction was demonstrated in contrast to the control group. 5) Calcitonin appears to facilitate Ca release through exerting actions on Ca transport system in the sarcoplasmic reticulum. From these results, it was shown that calcitonin appears to possess an activity to elevate contractile ability of skeletal muscles. This activity is considered to be derived from its effect on sarcoplasmic reticulum. This activity of calcitonin on contractile function of skeletal muscles indicates the presence of a mechanism relating to skeletal muscles in the analgesic effect on low back pain in osteoporosis.

Animals↗
PubMed1976

Conservative treatment in spondylolisthesis.

Spondylolisthesis occurs mainly at the L5-S1 interval, thus involving the dynamic segment. The general incidence is between 2 and 5 per cent, but about half of these patients are asymptomatic. The conservative therapy for the asymptomatic patients includes preventive measures such as correction of poor posture, elimination of stressful occupational requirements, avoidance of certain spine movements, and special sport activities. The mild to moderate low back pain syndrome requires alleviation of anxiety, analgesics and muscle relaxants, deep heat and relaxation and range of movement exercises. The severe low back pain which may prevent neurological deficit as well, should include a brief period of bed rest with strong analgesics and then gradual mobilization. In most instances, corsets are not required. Paravertebral blocks may be administered in special recalcitrant cases.

Back Pain↗
PubMed1975

Birth trauma to muscles in babies born by breech delivery and its possible fatal consequences.

Dissection and histological examination was made of the muscles of 86 babies who died after breech delivery, and of 38 babies who died after vertex presentation. A control group of 50 surviving breech-delivered babies was examined clinically and the results compared. It was concluded that the most common type of birth trauma to a baby born by breech delivery is injury to muscles and soft tissues of the back and lower extremities, which is often extensive. In some severly injured babies histological examination of organs revels signs of crush syndrome and disseminated intravascular coagulation. It is suggested that the extensive muscle trauma forms the background of these fatal conditions.

Anal Canal↗
PubMedDate not supplied

Segmental hypermobility in lumbar spine and entrapment of dorsal rami.

Low back pain patients (N = 18) having segmental hypermobility in one lumbar segment and healthy controls (N = 13) were chosen for this study. Patients had no other structural spinal pathology except displacement of one vertebra to another in lateral X-ray bending pictures. Kinetic intramuscular EMG-activity from paraspinal muscles was studied off-line during back flexion and reextension. Routine needle EMG study of paraspinal muscles was also performed in addition to measurements of the tibial nerve H-reflexes and peroneal F-responses. Results showed that the number of MUAPs in erector spinae muscle on voluntary efforts was rarefied at hypermobile levels, and spontaneous activity, positive sharp waves and high frequency discharges were found in more than half of the patients in paraspinal muscles, usually at hypermobile levels only. No signs of proximal nerve root compression were found. This indicates neuropathy of dorsal rami at the instable level.

Adult↗
PubMed1998

Sacrospinalis muscle-pedicle bone graft in posterolateral fusion for spondylolisthesis.

Twenty three patients with lumbar spondylolisthesis (6 Grade I, 14 Grade II and 3 Grade III) with low back pain, and radicular pain in 14, were treated surgically when they failed to respond to conservative treatment. Their average age was 33.2 years. Bilateral posterolateral spinal fusions with autologous iliac bone chips, supplemented by a sacrospinalis muscle-pedicle bone graft on the left side, were undertaken after laminectomy and foraminotomy in all except in two adolescents, where laminectomy and foraminotomy were avoided. The period of follow-up varied from 26 to 126 months (average 65.3 months). The results in 11 (48%) patients were excellent, 9 (39%) were good, 2 (9%) fair and one (4%) poor. There was a higher incidence (87%) of good quality of osseous fusion on the left side, where the sacrospinalis muscle-pedicle bone graft was used, compared to the right, where 70% of fusions were satisfactory. Function improved in 91% of the patients. Neither scoliosis nor weakness of the extensor muscles of the back developed due to reanchorage of the sacrospinalis muscle to the lumbosacral spines.

Activities of Daily Living↗
PubMedDate not supplied

Low back pain: risk evaluation and preplacement screening.

As screening tests in a currently asymptomatic population, all of the available methods for predicting low back pain and disability have serious technical, ethical and legal limitations. From a technical point of view, none of the predictive tests appear to have sufficient sensitivity or specificity to justify routine usage. The most sensitive indicator (a past history of low back pain) lacks reliability and specificity. Muscle strength-testing may be predictive of future musculoskeletal injury as part of a well-designed program that considers specific job demands in relation to specific worker capabilities. Unfortunately, the conditions necessary for a well designed program--a large number of predictable high-risk jobs that have measurable specific demands that can be reproduced reliably in a testing situation--are rarely met. In the future, the use of computer-assisted multivariate models analogous to those used in the prediction of cardiovascular risk may be capable of integrating information about an individual's medical history, physical exam, physical capacity and other tests with specific job requirements to give us a more accurate prediction of the future risk of back pain and disability. If such predictive models are ever developed and verified, it would then be appropriate to examine various interventions and their effectiveness in modifying risks for the population and the individual worker. From a legal point of view, all of the techniques described hold potential for significant discrimination against legally protected groups. Making employment decisions with regard to a past history of low back pain or on the basis of an x-ray will lead to systematic age discrimination and discrimination against the handicapped. The use of muscle strength-testing will systematically discriminate against women and certain ethnic groups. The ethical implications of predictive screening for low back pain clearly depends on what is done with the information that is garnered from such tests. If the information is used only to make a safe job placement for an individual, and this placement does not affect the individual's salary or future job possibilities, then the testing program may have a net social value to the extent that it leads to true prevention of low back pain and disability. If the tests are used merely to reduce employer liability by refusing employment to those who are thought to be at "high risk," the technical, legal and ethical limitations will far outweigh any perceived benefits.

Back Pain↗
PubMed1996

Support for a linear length-tension relation of the torso extensor muscles: an investigation of the length and velocity EMG-force relationships.

This study investigated the hypothesis that the length-tension relation of the torso erectors would be linear, mirroring the observed linear increase in extension strength capability toward full flexion. The effect of torso extension velocity on the tension capability of these muscles was also investigated for common motion speeds. A myoelectric-based approach was used wherein a dynamic biomechanical model incorporating active and passive tissue characteristics provided muscle kinematic estimates during controlled sagittal plane extension motions. A double linear optimization formulation from the literature provided muscle tension estimates. The data of five male subjects supported the hypothesis of a linear length-tension relation toward full flexion for both the erector spinae and latissimus muscles. Velocity trends agreed with the predicted by Hill's exponential relation, although linear trends were found to fit the data almost as well. The results have implications for muscle tension estimation in biomechanical torso modeling, and suggest a possible low back pain injury mechanism through tissue strain while lifting in fully flexed postures.

Abdominal Muscles↗
PubMed1986

Lumbar spine orthosis wearing. II. Effect on trunk muscle myoelectric activity.

The effects of wearing commonly prescribed low-back braces and corsets on myoelectric signal levels in the erector spinae and oblique abdominal muscles were investigated. A lumbosacral corset, a chairback brace, and a molded thoracolumbosacral orthosis (TLSO) were studied. Nineteen tasks involving sitting and standing were performed by five healthy adult men. Myoelectric signal levels measured when wearing each orthosis were compared with those measured when performing the same task while wearing no orthosis. The changes in mean myoelectric signal levels ranged from a 9% reduction to a 44% increase when the lumbosacral corset was worn, from a 27% reduction to a 25% increase when the chairback brace was worn, and from a 38% reduction to a 19% increase when the TLSO was worn.

Adult↗
PubMed1989

Electromyographic recordings of 5 types of low back pain subjects and non-pain controls in different positions.

Surface EMG recordings of bilateral paraspinal muscle tension were measured on 207 subjects (29 non-back pain controls, 20 individuals with spondyloarthritis, 52 with intervertebral disk disorders, 66 with unspecified musculoskeletal backache, 17 with some combination of the above 3 groups and 23 subjects with other types of back pain, including unknown, scoliosis and psychogenic) in 6 positions: standing, bending from the waist, rising, sitting with back unsupported, sitting with back supported and prone. Results of both individual and group analyses revealed a significant main effect of diagnosis. Post hoc analyses (Duncan's) revealed controls to have significantly lower overall EMG levels than the intervertebral disk disorders and unspecified musculoskeletal backache groups. A significant diagnosis by position interaction was observed. Analysis of simple main effects revealed this to be due primarily to control subjects during the standing position having lower EMG levels than all other groups, and intervertebral disk disorder subjects having higher EMG levels than all other groups during the supported sitting position. The importance of clearly defined diagnostic categories in low back pain research and the utility of measuring subjects in various positions are discussed.

Adult↗
PubMed2002

A dynamic 3D biomechanical evaluation of the load on the low back during different patient-handling tasks.

The objective of this study was to investigate the low-back loading during common patient-handling tasks. Ten female health care workers without formal training in patient handling performed nine patient-handling tasks including turning, lifting and repositioning a male stroke patient. The low-back loading was quantified by net moment, compression, and shear forces at the L4/L5 joint, measured muscle activity (EMG) in erector spinae muscles and rate of perceived exertion (RPE; Borg scale). The experiments were videotaped with a 50Hz video system using five cameras, and the ground and bedside reaction forces of the health care worker were recorded by means of force platforms and force transducers on the bed. The biomechanical load was calculated using a dynamic 3D seven-segment model of the lower part of the body, and the forces at the L4/L5 joint were estimated by a 14 muscles cross-sectional model of the low back (optimisation procedure). Compression force and torque showed high task dependency whereas the EMG data and the RPE values were more dependent on the subject. The peak compression during two tasks involving lifting the patient (4132/4433N) was significantly higher than all other tasks. Four tasks involving repositioning the patient in the bed (3179/3091/2932/3094N) did not differ, but showed higher peak compression than two tasks turning the patient in the bed (1618/2197N). Thus, in this study the patient-handling tasks could be classified into three groups-characterised by lifting, repositioning or turning-with different levels of peak net torque and compression at the L4/L5 joint.

Adult↗
PubMed2004

Paraspinal muscles and intervertebral dysfunction: part two.

BACKGROUND: One of the diagnostic characteristics of the manipulable spinal lesion--a musculoskeletal disturbance that is claimed to be detected with manual palpation and corrected with manipulation--is said to be altered segmental tissue texture. Little evidence for the nature of abnormal paraspinal tissue texture exists, but indirect evidence from experimental studies supports the plausibility of the concept of protective muscle spasm, although investigations of increased paraspinal electromyography (EMG) associated with low back pain suggests complex changes in motor control rather than simple protective reflexes. OBJECTIVES: To review the literature for evidence that may support or refute proposed explanations for clinically observed altered paraspinal tissue texture associated with the manipulable spinal lesion. This review aims to highlight areas that require further research and make recommendations for future studies. Data Source MEDLINE and CINAHL databases were searched using various combinations of the keywords paraspinal, muscle, palpation, EMG, spine, low back pain, pain, myofascial, hardness, manipulation, reliability, and somatic dysfunction, along with searching the bibliographies of selected articles and textbooks. Data Extraction All relevant data were used. RESULTS: Decreased paraspinal muscle activity and strength associated with low back pain is well established, and there is evidence of changes in muscle fiber composition and localized selective multifidus atrophy. Disturbances in microcirculation have been implicated in nonparaspinal muscle pain. The effect of spinal manipulation on paraspinal EMG activity is inconclusive but promising. CONCLUSION: Little direct evidence exists to support the existence or nature of paraspinal tissue texture change that is claimed to be detected with palpation. The proposal of segmental reflex paraspinal muscle contraction was not supported, at least in association with low back pain. There appears to be a complex relationship between deep paraspinal muscle inhibition during dynamic activity and nonvoluntary guarding behavior during static activity. The relationship between these findings and palpable tissue change is speculative, but increased activity, decreased activity, or both may be responsible for paraspinal tissues detected as abnormal with palpation. Recommendations are outlined for future research.

Atrophy↗
PubMed2000

Selective paraspinal muscle amyotrophy.

A 56-year-old female presented with mild low back pain. Examination revealed severe, selective atrophy of the thoracic and lumbar paraspinal muscles. Fibrillations were seen in the paraspinal muscles on EMG. Limb EMG was normal. Biopsy of the gluteus maximus was normal. Paraspinal muscle biopsy revealed neurogenic features. Atrophy of the thoracic and lumbar paraspinal muscles was noted on magnetic resonance imaging. This patient has selective amyotrophy of the thoracic and lumbar paraspinal muscles. This may be an addition to the spectrum of 'benign focal amyotrophy'. The differential diagnosis of paraspinal muscle weakness is discussed.

Biopsy↗
PubMed1991

Power spectrum analyses of electromyographic activity. Discriminators in the differential assessment of patients with chronic low-back pain.

Some parameters of the electromyographic power spectrum of the paraspinal muscles were recorded and analyzed with regard to their ability to discriminate between normal controls and patients with back pain classified as "avoiders" or "confronters" by their responses to the Pain Behavior Checklist. In terms of the activity of the multifidus muscle, the avoider group displayed spectral changes towards lower frequencies, reduced variability in the density spectrum, and higher values of estimated initial frequencies. Measures of the activity of the iliocostalis lumborum did not contribute in any significant way to these group differences. Based on these findings, and on the available literature concerning the histology and physiology of paraspinal muscles, it is proposed that the observed characteristics of the avoider group may be due to a reduced ratio of slow twitch to fast twitch muscle fibers in the multifidus.

Back Pain↗
PubMed2004

The application of surface electromyography in the assessment of ergonomic risk factors associated with manual lifting tasks.

The purpose of this study was to evaluate the ergonomic risk factors associated with manual lifting tasks using surface electromyography (EMG). 13 volunteers lifted loads of 6 and 13 kg at two speeds and at two horizontal distances in 3 different postures and three boxes of different sizes, from floor to knuckle height, performing 72 lifting tasks. For each lift, the surface electromyography signals from the erector spinae muscles, bilaterally at T10 and L3, was recorded. The ergonomic risk factors associated with manual lifting tasks were evaluated by comparing the average amplitude of EMG signals from the erector spinae muscles. The EMG average amplitude for lifting the load of 13 kg was 14.3% greater than that for lifting the load of 6 kg (t=-10.93, P<0.01). The EMG average amplitude at the site of L3 was 10.3% greater than that at the site of T10 (t=-7.98, P<0.01). The EMG average amplitude when performing "fast" lift was 5.9% greater than the "slow" lift (t=-4.63, P<0.01). The posture of lifting affected the EMG average amplitude. It was lowest with semi-squat posture and greatest with squat posture (F=27.76, P<0.01). The result of multiple stepwise regression analysis showed that the loads of lifting, the size of box, horizontal distance, posture of lifting, the site of the spine subjected to force, lifting speed were the factors affecting the EMG average amplitude. The most significant factor was the loads of lifting, followed by the site of the spine subjected to force and the lifting speed in terms of risk. The ergonomic risk factors associated with manual lifting tasks includes the loads, posture, lifting speed, horizontal distance, the site of the spine subjected to force etc. The results of signal amplitude of EMG from the erector spinae muscles showed that semi-squat posture is the best posture for lifting tasks.

Adult↗
PubMed1993

Spectral analysis of erector spinae EMG during intermittent isometric fatiguing exercise.

The applicability of EMG spectral analysis in the study of muscular fatigue of the erector spinae muscle was investigated. At three locations (L1, L2, L5) of the erector spinae muscle, representing different functional parts, EMG was sampled during fatiguing intermittent isometric extension of the trunk. The multifidus muscle (L5) appeared to show the most consistent changes of the EMG power spectrum as a consequence of fatigue. Whether the effects of the increase in muscle temperature on the power spectrum could be eliminated by low-pass filtering the data (60 Hz and 40 Hz) was also investigated. It was expected that this would make it possible to detect better the effects of fatigue on the firing characteristics of the motorunits by the inherent changes in the power spectrum. Low-pass filtering did not cause a more significant trend of the median frequency of the power spectrum. Future research will have to explore which parts of the power spectrum are affected by an increase of the muscle temperature.

Adult↗
PubMed2002

Regional distribution of slow-twitch muscle fibers after reinnervation in adult rat hindlimb muscles.

In adult rats, the sciatic nerve was unilaterally sectioned and reunited above the knee. Following a survival time of 21 weeks, five muscles were removed from both lower hindlimbs after determining their intra-limb positions. In each muscle, cryostat sections from seven equidistant proximo-distal levels were stained for myofibrillar ATPase. Intramuscular positions were determined for all slow-twitch type I fibers. Within each muscle, type I fibers were heterogeneously distributed, and the direction of type I fiber accumulation was, on average, almost identical in reinnervated muscles and contralateral controls. Furthermore, as in controls, a proximo-distal decline of type I fiber density was found in reinnervated muscles. Compared to contralateral controls, reinnervated muscles consistently showed a very high number of type I fibers at close interfiber distances, indicating respecification of muscle fiber types by the ingrowing nerve fibers. The results suggest that slow-twitch motor axons preferentially grew back toward the original slow-twitch muscle regions.

Anatomy, Cross-Sectional↗
PubMed1985

Simple and quick non-invasive evaluation of circulatory condition of cerebral arteries by clinical application of the "Bi-Digital O-Ring Test".

Using the "Bi-Digital O-Ring Test," generalized abnormal circulation of the distribution of the 3 cerebral arteries at each side of the brain (i.e., anterior cerebral artery, middle cerebral artery and posterior cerebral artery) can be predicted, without any expensive instruments usually in a few minutes. When abnormality was found in the bifurcation area of the common carotid artery by the "Bi-Digital O-Ring Test," there were always abnormal findings of the area of the brain where circulation was coming from either one or both of the anterior or middle cerebral arteries. When abnormal "Bi-Digital O-Ring" response was found at the vertebral artery and posterior cerebral artery representation point, discovered by the author, at the side of the 6th cervical vertebra (corresponding to the entry point of the vertebral artery into the transverse foramen), the areas of the cerebrum, cerebellum and brain stem where circulation is coming from the posterior cerebral artery, basilar artery and vertebral artery were also abnormal. Most of these abnormalities were found to be associated with problems of the cervical vertebrae and spastic muscles of the neck and shoulders and are often reversible. In this study, the author was able to differentiate abnormal brain circulation of any major branch of arteries in the brain due to organic changes or functional reversible changes by relaxing these spastic muscles and improving the circulation of the neck and shoulder area by giving either manual acupuncture, massage, or transcutaneous electrical stimulation. This in turn often improved brain circulation. If it was a functional abnormality, within a few minutes after one of these procedures the "Bi-Digital O-Ring Test" usually showed normal response or improvement. However, if it was an organic abnormality, the abnormality remained. When the supra-orbital arterial blood pressure at both sides of the forehead decreases below 40 or 30 mmHg, most patients develop so-called "Cephalic Hypotension Syndrome," which is characterized by sleep disturbance pattern; difficulty in concentration; easy forgetfulness of recent events; irritability; decreased pain threshold with or without depression; spastic skeletal muscles, particularly the neck, shoulder and back areas. All of these symptoms can be explained by decreased circulation to the Nucleus Raphe Centralis Superior (controls sleep and waking pattern), Nucleus Raphe Magnus (serotonin & modulation of pain), Nucleus Reticularis Giganto Cellularis (controls muscle tone), etc. in reticular formation.(ABSTRACT TRUNCATED AT 400 WORDS)

Acupuncture Therapy↗