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PubMed1992

Trunk-muscle strength during concentric and eccentric contraction: a comparison between healthy subjects and patients with chronic low-back pain.

The physical evaluation and exercise program of trunk muscles in patients with chronic low-back pain (CLBP) is still controversial. Many studies have been performed in the isometric and/or concentric contraction mode. Few data, however, have been reported on trunk-muscle strength during eccentric contraction, which plays a significant role in functional activities. To evaluate whether trunk-muscle strength on eccentric contraction could be applicable to the assessment and exercise of the patients with CLBP, trunk strength was measured in 20 healthy men and 16 healthy women, as well as 15 male and 10 female patients with CLBP. Maximum voluntary concentric and eccentric strength was measured during attempted flexion and extension in a seated position. In the healthy subjects, the maximum torque of extensors was greater than that of the flexors during both concentric and eccentric contraction (p less than 0.05). In flexors and extensors, maximum torque exerted on the eccentric contraction was always greater than that on the concentric contraction (p less than 0.05). Although strength was likely to be weaker in the patients with CLBP than in the healthy subjects, there were no statistical differences between the two groups. In terms of the flexor/extensor ratio of maximum torque, there were also no statistical significances between the two groups in either contraction mode. In the flexors, correlation coefficient (r) between concentric and eccentric torque was 0.84 for the healthy subjects and 0.48 for the CLBP subjects (p less than 0.05). In the extensors, the coefficient was 0.90 for the healthy patients and 0.71 for the CLBP patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Asymmetrical loads and lateral bending of the human spine.

The human spine is modelled as a cantilever-type beam column. Under the influence of static asymmetrical loads, muscle and low-back forces are predicted from a hypothetical but revealing model. Such forces produced by asymmetrical loads are much larger than for a corresponding symmetrical load. Asymmetrical loads can encourage, especially in young schoolchildren, lateral bending of the spine by alleviating muscle and low-back forces. This could possibly be a factor contributing to the surprisingly high percentage of schoolchildren with measurable scoliotic curves. The wearing of knapsack-type bags is advocated.

Adolescent↗
PubMed1985

The effects of dietary restriction and exercise on the volume of adipocytes in two intra-orbital depots in the guinea-pig.

The volume of adipocytes in two intra-orbital sites and fourteen superficial and intra-abdominal sites, and the total adipocyte complement have been measured in virgin and reproductive guinea-pigs maintained on several different regimens of diet and exercise. The adipocytes around the ocular muscles at the back of the orbit (peripheral fat) are always larger than those just behind the eyeball (orbital fat). The adipocytes in both the intra-orbital sites are significantly larger in guinea-pigs whose total adipocyte complement is smaller than one standard deviation from the mean, than in those which have a normal-size or large adipocyte complement. The volume of intra-orbital adipocytes correlates very significantly with the volume of adipocytes in superficial and intra-abdominal sites in guinea-pigs which have large adipocyte complements, correlates weakly in those with normal adipocyte complements and not at all in those with small adipocyte complements. It is suggested that there may be fewer intra-orbital adipocytes in animals which have small adipocyte complements, and that, because the intra-orbital adipose tissue occupies a constant volume, the adipocytes in these sites become larger when they are less numerous.

Adipose Tissue↗
PubMed1986

Comparison of electromyographic response patterns during posture and stress tasks in chronic low back pain patterns and control.

Activity of the paraspinals, abdominals, and hip extensor muscles, heart rate, and skin conductance were measured in 13 chronic low back pain patients (CLBP) and 13 controls during static postures and psychological stress. After 10 min of baseline-rest, a subject was tested during standing, 45 degrees bend, maximum bend, posterior and anterior pelvic tilts, sitting, and supine with knees up, followed by mental arithmetic and the cold pressor. The postures were grouped into supported, balanced, and unbalanced categories. Multivariate analyses of variance revealed differences due to posture categories, but not due to group membership. It was concluded that while work is needed to understand normal muscle function during common movements, there is no compelling evidence that back muscle functioning in CLBP patients differs significantly from control subjects.

Adult↗
PubMed1991

Force response to rapid length change during contraction and rigor in skinned smooth muscle of guinea-pig taenia coli.

1. Mechanical transients in fibre bundles of skinned smooth muscle of guinea-pig taenia coli at 21-22 degrees C were investigated by recording tension responses to length changes of up to 9%, complete within 0.3 ms. 2. The length-force relationship, recorded continuously during rapid stretch of a Ca(2+)-activated contracted muscle, was linear up to at least 2.5 times the isometric force, corresponding to a stretch of about 1%. The slope of the relationship (stiffness) increased with the velocity of stretch. 3. During rapid release (about 120 muscle lengths s-1) the length-force relationship was linear down to about 50% of the initial isometric force, reached at about 80 microseconds after the beginning of the release. At lower force the length-force relationship was concave upwards. The linear portion extrapolated to zero force at about -0.008 muscle lengths. In large releases the length-force plot approached the force baseline under an acute angle, and negative force was transiently exerted. 4. When the muscle was stretched back to the initial length after a shortening step, force transiently rose above the isometric force, but decayed back within a few milliseconds. Stiffness at the time of restretch was compared with that in the initial shortening step by plotting force vs. length, and was found to be decreased to 63% within 0.3 ms of a step to zero force. Stiffness decreased further with time at zero force, and after 256 ms was about 29% of the isometric value. 5. In rigor, caused by the introduction of ATP-free solution during the plateau of isometric contraction, fibre tension decreased to about 30% of the active tension, whereas stiffness relative to force increased; 82% of the initial stiffness in rigor was detected in a restretch immediately after a shortening step, decreasing to 59% at 256 ms. When the fibre was activated at suboptimal [Ca2+] to cause the same force as in rigor, stiffness was lower than in rigor and decreased more after a release. 6. After completion of a release-stretch cycle, stiffness was rapidly restored to the same value as in isometric contraction. Test stretches at different points in time after completion of the cycle revealed that most of the stiffness had been restored within 1 ms of the restretch, occurring concomitantly with a decay in force.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed2005

Corticospinal excitability in patients with chronic low back pain.

OBJECTIVE: This study was designed to investigate corticospinal excitability of lumbar muscles using transcranial magnetic stimulation (TMS) in patients with chronic low back pain and correlate this with self-rated measures of disability and pain. METHODS: Twenty-four patients with chronic low back pain and 11 healthy control subjects were used in this study. TMS was delivered through an angled double-cone coil, with its cross-over on the vertex and a posterior-to-anterior current flow in the brain. Electromyographic (EMG) recordings were made from erector spinae (ES) muscles at the fourth lumbar level. Motor cortical excitability was assessed using motor threshold (MTh) for motor evoked potentials (MEPs) and threshold for silent period (SP) during facilitation of the back muscles. Latency, duration, and area of MEPs and SPs were also measured. RESULTS: The latency, duration, and size of MEPs and SPs did not differ between the left and right ES muscles in either the patients or the control subjects and also did not differ between the patients and the control subjects. However, there was a significantly higher MTh and threshold for the SP in the patients as compared with the control subjects; the full significance of this requires further investigation. Interestingly, there was a positive correlation between the self-rated measure of disability (the Oswestry Disability Index score) and both the MTh and the threshold for the SP in the patients. There was also a positive correlation between the self-rated index of back pain and the threshold for the SP in the patients. This finding of an association between clinical and neurophysiologic measures reinforces the need for further research to establish the clinical relevance of these rises in MTh and SP threshold. CONCLUSIONS: In summary, this study has revealed that corticospinal excitability, driving ES muscles close to the site of pain, is lowered in patients with chronic low back pain.

Adult↗
PubMed1998

Efficacy of a stress management program for patients with hepatocellular carcinoma receiving transcatheter arterial embolization.

Transcatheter arterial embolization (TAE), a common treatment for patients with unresectable hepatocellular carcinoma (HCC), can provoke severe physical discomfort and psychologic stress. The purpose of this study was to investigate the effect of a combination of health education, muscle relaxation, and back massage on reducing physical and psychologic stress in HCC patients receiving TAE. A quasi-experimental design was used. Forty patients with HCC (30 men and 10 women) with a mean age of 57 +/- 12 years were recruited and randomly assigned to the control or experimental group. The effectiveness of the stress management program was evaluated using a knowledge questionnaire, a worry inventory, a state-trait anxiety inventory, and a physical distress scale. After completing the stress management program, the experimental group had a greater mean increase in knowledge score than the control group (5.1 vs 0.8, p < 0.0001) and a greater mean decrease in worry score (-8.2 vs 1.1, p < 0.0001). The mean decrease in the anxiety score in the experimental group was also significantly greater than in the control group before TAE (-5.8 vs 3.2, p < 0.001) and 2, 4, 6, and 7 days after TAE (-8.2 vs 7.1, p < 0.001; -8.7 vs 3.2, p < 0.001; -9.8 vs -2.1, p < 0.05; -11 vs -0.9, p < 0.05). The patients in the experimental group had a smaller mean increase in physical distress score than the control group at 2, 4, 6, and 7 days after TAE (34.7 vs 50.2, 20.9 vs 29.6, 10.6 vs 18.2, 3.9 vs 11.2, all p < 0.05). This stress management program effectively reduces the stress of HCC patients undergoing TAE.

Adult↗
PubMed1993

Significant improvement of stiff-person syndrome after paraspinal injection of botulinum toxin A.

Following several months of low back pain, a 36-year-old man developed progressive stiffness of the abdominal, low back, and thigh muscles. On examination, these muscles demonstrated marked hypertonia consistent with the clinical diagnosis of stiff-person syndrome. The patient demonstrated increased lumbar lordosis and had focal hyperhidrosis at different sites. Electromyography showed continuous activity of the paraspinal and thigh muscles, and serum and cerebrospinal fluid antibodies to glutamic acid decarboxylase (GAD) were markedly elevated. Diazepam and Lioresal offered partial pain relief. Paraspinal muscle administration of botulinum toxin A reduced the tone of paraspinal and thigh muscles significantly and resulted in marked improvement of ambulation and cessation of pain.

Adult↗
PubMed1998

Effect of increasing running velocity on electroencephalogram in a field test.

This study was designed to measure the electroencephalogram (EEG) after exercise with increasing intensity. In a field test with increments in running velocity a 2-min EEG was recorded, together with blood lactate concentration and heart rate, after each stage. An individual protocol was used, with up to six stages of running to ensure comparability of exercise intensity among the subjects, in each of 19 athletes (17 men, 2 women) experienced in leisure-time running. The exercise consisted initially of three running stages of aerobic exercise intensity without blood lactate accumulation followed by stages with an increase of lactate concentration. The protocol of the field test led to a progressive increase in cortical activity directly after the stages without blood lactate accumulation mainly in the delta frequency band, followed by theta and alpha-1 frequency band, and less pronounced in the alpha-2 and in the beta frequency bands. After the stages with an onset and further increase of blood lactate accumulation significant decreases in the beta-2, beta-1 and alpha-1 frequency bands occurred predominantly in temporal (T3, T4, T5, and T6) and occipital (O1, and O2) electrode positions, indicating a stage-by-stage decrease of activity. This decrease may be explained by feed-back from working muscle, via afferents to the cortex from intero- and proprio-receptors and affective processes. This could suggest that through a higher running intensity indicated by an onset of blood lactate accumulation metabolic and mechanical changes led to alterations within the afferent systems influencing the level of cortical activity.

Adult↗
PubMed2003

[Validation of the German Mainz Pain Staging System in different pain syndromes].

OBJECTIVE: Our study was carried out to clarify whether differences in pain intensity,pain-related disability,depression and quality of life change with respect to the stage of chronicity of the Mainz Pain Staging Study (MPSS) in different pain syndromes. Keywords. METHODS: All patients with an initial pain clinic consultation from July 2000 to July 2001 and suffering from four major pain syndromes ("headache", "neuropathic pain", "back pain" or "muscle and joint pain") were included. Indicators of validity were several self-rating scales from the German pain questionnaire of the German Chapter of the International Association for the Study of Pain (DGSS). Patient data were collected using QUAST, a database environment specifically developed for documentation and quality assurance in pain therapy. An assessment was made for each of the four major diagnoses to determine whether patients in the three chronicity stages differed in their psychometric test results. In addition,the four diagnosis groups were tested for differences from one another. RESULTS: A total of 862 patient charts with documented pain syndromes and MPSS were extracted and analyzed. The extent of the subjective psychosocial stress and disability increased in all diagnosis groups and was correlated with the chronicity stage. The proportion of patients with an indication of clinically relevant depression (ADS score >23) increased with chronicity regardless of the pain diagnosis. The four main diagnosis groups differed with respect to the chronicity stage according to MPSS (P<0.001), with headache patients being classified predominantly as stage I. Patients with an additional pain diagnosis had a higher chronicity stage (P<0.001). CONCLUSION: Our results underline the validity of the MPSS for the four diagnosis groups examined; however, pain diagnosis must be controlled in all studies using chronicity stage as an independent variable, e.g., therapy studies. For optimal results physicians must closely follow the test instructions of the MPSS.

Databases, Factual↗
PubMed2005

The adult scoliosis.

Adult scoliosis is defined as a spinal deformity in a skeletally mature patient with a Cobb angle of more than 10 degrees in the coronal plain. Adult scoliosis can be separated into four major groups: Type 1: Primary degenerative scoliosis, mostly on the basis of a disc and/or facet joint arthritis, affecting those structures asymmetrically with predominantly back pain symptoms, often accompanied either by signs of spinal stenosis (central as well as lateral stenosis) or without. These curves are often classified as "de novo" scoliosis. Type 2: Idiopathic adolescent scoliosis of the thoracic and/or lumbar spine which progresses in adult life and is usually combined with secondary degeneration and/or imbalance. Some patients had either no surgical treatment or a surgical correction and fusion in adolescence in either the thoracic or thoracolumbar spine. Those patients may develop secondary degeneration and progression of the adjacent curve; in this case those curves belong to the type 3a. Type 3: Secondary adult curves: (a) In the context of an oblique pelvis, for instance, due to a leg length discrepancy or hip pathology or as a secondary curve in idiopathic, neuromuscular and congenital scoliosis, or asymmetrical anomalies at the lumbosacral junction; (b) In the context of a metabolic bone disease (mostly osteoporosis) combined with asymmetric arthritic disease and/or vertebral fractures. Sometimes it is difficult to decide, what exactly the primary cause of the curve was, once it has significantly progressed. However, once an asymmetric load or degeneration occurs, the pathomorphology and pathomechanism in adult scoliosis predominantly located in the lumbar or thoracolumbar spine is quite predictable. Asymmetric degeneration leads to increased asymmetric load and therefore to a progression of the degeneration and deformity, as either scoliosis and/or kyphosis. The progression of a curve is further supported by osteoporosis, particularly in post-menopausal female patients. The destruction of facet joints, joint capsules, discs and ligaments may create mono- or multisegmental instability and finally spinal stenosis. These patients present themselves predominantly with back pain, then leg pain and claudication symptoms, rarely with neurological deficit, and almost never with questions related to cosmetics. The diagnostic evaluation includes static and dynamic imaging, myelo-CT, as well as invasive diagnostic procedures like discograms, facet blocks, epidural and root blocks and immobilization tests. These tests may correlate with the clinical and the pathomorphological findings and may also offer the least invasive and most rational treatment for the patient. The treatment is then tailored to the specific symptomatology of the patient. Surgical management consists of either decompression, correction, stabilization and fusion procedures or a combination of all of these. Surgical procedure is usually complex and has to deal with a whole array of specific problems like the age and the general medical condition of the patient, the length of the fusion, the condition of the adjacent segments, the condition of the lumbosacral junction, osteoporosis and possibly previous scoliosis surgery, and last but not least, usually with a long history of chronified back pain and muscle imbalance which may be very difficult to be influenced. Although this surgery is demanding, the morbidity cannot be considered significantly higher than in other established orthopaedic procedures, like hip replacement, in the same age group of patients. Overall, a satisfactory outcome can be expected in well-differentiated indications and properly tailored surgical procedures, although until today prospective, controlled studies with outcome measures and pre- and post-operative patient's health status are lacking. As patients, who present themselves with significant clinical problems in the context of adult scoliosis, get older, minimal invasive procedures to address exactly the most relevant clinical problem may become more and more important, basically ignoring the overall deformity and degeneration of the spine.

Adult↗
PubMed2003

Upper thoracic sympathetic surgery. Open surgical techniques.

Four open surgical approaches have been used to perform upper thoracic sympathectomy. The posterior approach requires access through the posterior muscles of the back, and rib transection. It is a painful operation that has been practically abandoned in favor of the other techniques. The anterior transthoracic approach consists of a formal thoracotomy and never gained popularity. The supraclavicular approach involves dissection of several important anatomical structures. It requires excellent surgical dexterity, but ensures the easiest postoperative recovery. The last approach involves a small transaxillary thoracotomy. Technically, it is the easier procedure. Both the supraclavicular and the transaxillary approaches were widely used until the advent of thoracoscopic surgery. The results (rate of success, recurrences, and sequelae) were similar for all techniques, depending on the procedure performed on the sympathetic chain, not on the access route. Open approaches for upper dorsal sympathectomy are not used any more except in the very rare cases in which thoracoscopy is unfeasible.

Humans↗
PubMed1986

Postural, epidemiological and biomechanical analysis of luggage handling in an aircraft luggage compartment.

Loading and unloading of luggage in an aircraft luggage compartment is carried out manually in uncomfortable working position. In this study, the loading work was analysed by surveying musculoskeletal symptoms, by recording the working postures and techniques at work, and by simulating the loading work in a mock-up of a DC-9 aircraft compartment. Low back, knees and shoulders were exposed to mechanical load in luggage handling. Video recordings were used to analyse posture and work technique. In the simulated luggage compartment in the laboratory, ground reaction forces, intra-abdominal pressure (IAP) and electromyography (EMG) signals from back and shoulder muscles were recorded simultaneously. Loading in sitting, squatting and kneeling were the postures that were used the most often. Unloading was generally less stressful than loading, involving less static work. Handling time was shortest when kneeling but knee symptoms were dominant. Lateral ground reaction forces and EMG activity from trapezius were highest when sitting, and IAP peaks were greatest when squatting. Thus each posture had major, though differing, disadvantages and a radical redesign of the DC-9 luggage compartment was clearly indicated.

Journal Article↗
PubMed1988

Syndrome of intradiscal lumbar herniation. Clinical presentation and management.

A syndrome of intradiscal lumbar herniation not associated with nerve root compression is described. The patients have a history similar to that seen in classic disk herniation, except the paresthesias and pain are "referred" roughly in a dermatomal distribution. On examination, limitation of range of motion of the back secondary to muscle spasm is noted; however, a positive straight leg-raising test result is not. Objective neurological findings are much less obvious than with radiculopathy. These patients may have "weakness" from lack of effort on their part during the examination. There is noted asymmetry in appropriate reflexes and also in the sensory examination. Standard imaging examinations are equivocal. If explored surgically, the findings are relatively unimpressive. These patients, if correctly identified, may be candidates for percutaneous nuclectomy.

Humans↗
PubMed1988

Efficacy of echo-Doppler examination for the evaluation of renovascular disease.

The accuracy of the diagnosis of renal artery stenosis using noninvasive echo-Doppler velocimetry was compared with that of angiography in 40 renal arteries. The duplex-Doppler signals were detected through the muscle of the back (the translumbar approach). Renal artery stenosis was diagnosed by three objectively defined Doppler parameters, the acceleration index (AI), the acceleration time (AT), and the acceleration time ratio (ATR). The normal range obtained on 11 control subjects was defined as AI greater than or equal to 3.78, AT less than or equal to 0.07 s, and ATR less than or equal to 1.35. High technological success (98%) was obtained using the translumbar approach. In comparison with angiography (cases of significant stenosis), the accuracy of the echo-Doppler method using the criteria of the AI was 95%, the sensitivity was 100%, and the specificity was 93%. This noninvasive method may be one of the most accurate screening methods for diagnosing significant renal artery stenosis.

Blood Flow Velocity↗
PubMed2005

Rupture of an expander prosthesis mimics axillary cancer recurrence.

Regional silicone gel migration from a ruptured breast implant has been reported at different locations including the upper extremity, chest wall muscles, axilla and back. We report a patient who presented with an axillary mass that mimicked a regional recurrence 5 years after breast cancer reconstruction with a latissimus dorsi musculocutaneous flap and silicon gel expander-prosthesis. Surgical exploration revealed that the mass contained silicone gel around the port of the breast expander that had ruptured. The mass was confluent with an intracapsular silicone leak through a tract along the tube of the expander port.

Breast Implants↗
PubMed2006

New indications for botulinum toxin in rheumatology.

Previously known only as a deadly bacterial poison responsible for severe paralysis, botulinum toxin is now a well-recognized therapeutic agent used to relieve involuntary movements, dystonia-related functional impairments, spasticity, and autonomic disorders such as hyperhidrosis. Musculoskeletal pain in patients with rheumatic disorders is among the emerging indications for botulinum toxin therapy. Preliminary data have been obtained in patients with cervical or thoracolumbar myofascial pain syndrome, chronic low back pain, piriformis muscle syndrome, tennis elbow, and stiff person syndrome. At present, the effects of botulinum toxin and its use for pain relief remain controversial. Carefully designed prospective trials are needed to investigate the efficacy and safety of botulinum toxin in pain disorders.

Arthralgia↗
PubMed1998

Repair of postinfarction ventricular septal defects.

Postinfarction ventricular septal defects complicate approximately 1% to 2% of cases of acute myocardial infarction and account for about 5% of early deaths after myocardial infarction. By differentiating the surgical treatment of these acquired lesions from the surgical approaches used to repair congenital ventricular septal defects and realizing the significance of differing anatomic locations of postinfarction ventricular septal defects, techniques have been developed that have improved salvage of patients suffering this catastrophic complication of myocardial infarction. The principles underlying these surgical techniques include (1) expeditious establishment of total cardiopulmonary bypass with moderate hypothermia and meticulous attention to myocardial protection; (2) transinfarct approach to ventricular septal defect with the site of ventriculotomy determined by the location of the transmural infarction; (3) thorough trimming of the left ventricular margins of the infarct back to viable muscle to prevent delayed rupture of the closure; (4) conservative trimming of the right ventricular muscle as required for complete visualization of the margins of the defect; (5) inspection of the left ventricular papillary muscles and concomitant replacement of the mitral valve only if there is frank papillary muscular rupture; (6) closure of the septal defect without tension, which in most instances will require the use of prosthetic material; (7) closure of the infarctectomy without tension with generous use of prosthetic material as indicated, and epicardial placement of the patch to the free wall to avoid strain on the friable endocardial tissue; and (8) buttressing of the suture lines with pledgets or strips of Teflon felt or similar material to prevent sutures from cutting through friable muscle.

Adult↗