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The electromyographic activity of the paraspinal muscles were examined to investigate the effects of chair sitting on muscle activation patterns and muscle fatigue. Twenty-four subjects were studied on the Balans, Back Up, and standard office chairs during a seated writing task and standing while performing a standardized muscle fatigue assessment test. The results of the study indicate that in 87.5% of the comparisons at the L3 site, the Back Up chair has lower readings of muscular effort compared to the Balans and office chair. During the muscle fatigue testing, the greatest amount of fatigue was noted in those subjects who sat in the Back Up chair last. When the Back Up chair was first or second, the least amount of fatigue was observed. The sEMG results supports a biomechanical model. The ergonomics of the Balans and office chairs give the least amount of support to the low back, while the Back Up chair provides the greatest amount of support. It is suggested that adequate pelvic girdle support during seated tasks will lower the threshold of back fatigue and thus facilitate return to work for low back pain patients. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented which studies the interaction between warfarin sodium and fluoxetine.

Momentary reductions in the electrical activity of working muscles (EMG gaps) contribute to the explanation for the relationship between psychosocial stress and musculoskeletal problems in computer work. EMG activity and gaps in the left and right trapezii were monitored in 23 participants under low and high mental workload (LMW and HMW) demands during computer data entry. Increases in EMG activity and decreases in EMG-gap frequencies in both left and right trapezius muscles were greater during HMW than LMW. In addition, heart period and end-tidal CO2 were lower during HMW, whereas self-reported mood states were higher during HMW. The correspondence between lower end-tidal CO2 and lower EMG-gap frequencies suggests that hyperventilation (overbreathing) may mediate trapezius muscle activation. The reduction of EMG gaps suggests that the salutary benefits of momentary rest from musculoskeletal work are diminished during mental stress.

The history of muscle pain and dysfunction is viewed through the lens of a four factor theory of histologic (tissue related) issues, psychologic (emotional) issues, sensory motor (movement) issues, and biomechanical (postural) issues. The historical antecedents of surface electromyography are reviewed.

Background: In the comprehensive assessment of painful conditions, dynamic surface electromyography (sEMG) and range of motion (ROM) recordings can provide information regarding muscle spasm, antalgic postures, fear of pain (protective guarding), muscle injury, and disordered movement caused by pain. This study examines ROM and sEMG patterns observed during cervical flexion., Objective: To demonstrate 2 distinctive sEMG recruitment and dynamic ROM patterns observed during cervical flexion and return to mid-line., Design: Single-subject design with independent measurement of dynamic ROM and sEMG., Setting: Applied clinical setting., Participants: Two subjects with normal ROM and cervical muscles were studied., Main Outcome Measure: One subject was studied with sEMG. looking at the cervical paraspinals and sternocleidomastoid muscles; the other subject was studied with an active ROM device. Three cervical movements were studied: lower cervical flexion, atlantoaxial (upper) cervical flexion, and a combination upper/lower cervical flexion., Results: The active ROM device indicates larger movements (higher degrees of flexion) for the lower cervical flexion compared with upper flexion. The combined movement indicates a differential movement from 2 spinal segments. The sEMG recordings indicated differential recruitment patterns. The sternocleidomastoid recruits briskly during the flexion phase of the upper cervical flexion movement, whereas the cervical paraspinals recruit briskly during return to mid-line when the lower cervical flexion is used. The combined upper then lower cervical flexion movement recruits both sets of muscles., Conclusions: The results of the study indicate 2 distinct movement patterns associated with upper versus lower cervical flexion and 2 distinct sEMG recruitment patterns. The study suggests that these 2 distinct movements involve 2 distinct cervical segments and are associated with recruitment of different muscle groups. Applied clinical research on the cervical spine should use sEMG recordings to assess both the upper and lower flexion movements as the standard for the study of cervical flexion.

A comparative analysis was conducted on a series of three experimental studies that examined the effect of various local and nonlocal (distant) complementary healing methods on multisite surface electromyographic (sEMG) and autonomic measures. The series concentrated sEMG electrode placement on specific neuromuscular paraspinal centers (cervical [C4], thoracic [T6], and lumbar [L3]), along with the frontalis region, due to the fact that these sites corresponded to the location of individual chakra centers as delineated in ancient Eastern medical and philosophical texts. It was hypothesized that the sEMG assessment procedure had the potential to provide objective, quantifiable correlates for complementary healing treatment effects, as well as assess the energy flow through the chakras during a healing treatment. The studies were the first of their kind to incorporate randomized, double-blind, placebo-controlled protocols in order to evaluate correlative neuromuscular multisite sEMG paraspinal measures with different complementary healing treatment interventions. Although the measurement protocols were similar between experiments, the results, demonstrated by the individual studies, varied. Whereas the overall findings of the series are encouraging because they indicate a potential objective scientific correlate to complementary healing treatment intervention, the results are considered preliminary in nature and appear to be linked to either the meditational experience of the subjects or dependent on the particular healer(s) used. Additional research is needed in order to establish the multisite sEMG assessment procedure as a reliable correlative measure for complementary healing treatment effects and to determine whether a consistent replicative treatment effect can be demonstrated independent of the specific subject population or practitioner(s) used.

The influence of complementary healing treatment on paraspinal electromagnetic activity at specific neuromuscular sites was examined in an exploratory pilot study that used a multisite surface electromyographic (sEMG) assessment procedure. The study was a replication and extension of previous research that indicated that complementary healing had a significant effect in normalizing the activity of the "end organ" for the central nervous system (CNS). Multisite sEMG electrodes were placed on the frontalis, cervical (C4), thoracic (T6), and lumbosacral (L3) paraspinals of 44 subjects who were divided into three groups: (1) students/patients of a Qigong practitioner (n = 16); (2) students/patients of a therapeutic touch (TT) practitioner (n = 14); and (3) nonbelievers in complementary healing (n = 14). A traditional ABAC experimental design was used with each subject evaluated for one 20-minute session that included four 5-minute segments. The purpose of this study was to measure the variable energizing effect of Qigong therapy along with the anecdotally and experimentally established relaxation effect of TT therapy relative to patient belief and expectancy. Treatment sessions consisted of Qigong and a modified form of TT intervention for all three groups. Due to the double-blind nature of the study, however, group 1 subjects were aware of only the Qigong intervention; group 2 subjects were aware of only the TT intervention, and group 3 subjects were informed that the study was designed to assess the neuromuscular activity of individuals in a seated position. The results indicated a statistically significant rise in electromagnetic activity for group 1 during the Qigong intervention segment (p < .024). Group 2 demonstrated a modest although overall nonsignificant decrease in multisite sEMG levels for both treatment protocols, whereas group 3 exhibited relatively consistent neuromuscular activity for both control and treatment segments. The results of this study are considered preliminary in nature, however, due to the potential influence of several confounds including psychophysiological factors, established behavior patterns, and the possibility for information transfer due to sensory cues.

This study was a replication and extension of previous research which indicated that Non-Contact Therapeutic Touch had a significant effect in normalizing the activity of the "end organ" for the central nervous system (CNS). The study utilized a randomized double-blind within subject crossover methodological design to examine the effect of nontraditional distant prayer upon autonomic and CNS parameters. The impact of complementary healing was assessed utilizing multi-site surface electromyographic (sEMG) recordings located at the frontalis, Cervical 4 paraspinals, Thoracic 6 paraspinals, and Lumbosacral 3 paraspinals. The autonomic indicators of physiological activity included hand temperature, heart rate, skin conductance levels (SCL), and blood volume pulse (BVP). Twenty-one subjects were randomly assigned to treatment and control conditions for two thirty minute evaluation sessions for a total of forty-two psychophysiological monitoring periods. All participants were blinded to the true nature of the experimental protocol as well as the fact that a healing study was being conducted in order to control for suggestion, expectation of healing, and the placebo effect. The analysis of autonomic indicators demonstrated a slight decrease in BVP and heart rate, coupled with a minor increase in SCL suggesting a mild "anticipatory effect" arousal trend. The data also showed that two of the four muscle regions monitored-T6 and L3 paraspinals-indicated a significant reduction in electromagnetic energy during and following the distant healing treatment intervention for a majority of the subjects. For example, the T6 SEMG showed significance at the p < .0002 level, while the L3 SEMG indicated significance at the p < .001 level.(ABSTRACT TRUNCATED AT 250 WORDS)

The reliability of a surface EMG scanning procedure was investigated for the right and left aspects of 10 muscle sites using a large clinical sample of 102 chronic pain patients. Two neutral postures (sitting/standing) were systematically studied on three occasions approximately one hour apart on the same day. The multivariate analysis of RMS microvolts indicated no significant effects for Age, Gender, Muscle site, Aspect or Period. The range of the Pearson correlations was 0.41 to 0.94 when all muscle sites, aspects, postures, and periods were considered. The median correlation was found to be 0.64. The pattern of reliability was seen to be slightly higher in the upper back while sitting, and slightly higher in the lower back while standing. The results indicate that with adequate attention to skin preparation, EMG sensors held in place by hand with a light pressure produce reliable results.

Therapeutic Touch (TT) has been an active change agent within the field of medicine since its introduction as a nursing intervention in 1975. A critical factor which has been missing from the research conducted in this area, however, is definitive scientific evidence or documentation that TT has an objective quantifiable impact upon the physiology of the subject. This study utilized a randomized ABAC methodological design to investigate the effect of TT without contact (NCTT) upon autonomic and CNS parameters. The subjects were blinded to the true nature of the experimental protocol as well as the fact that a healing study was being conducted in order to control for placebo and expectation effects. The impact of NCTT was assessed by multi-site surface EMG recordings located at the Frontalis, Cervical 4 paraspinals, Thoracic 6 paraspinals, and Lumbosacral 3 paraspinals. Autonomic indicators of physiological activity were also monitored and included hand and head temperature, heart rate, and end tidal CO2 levels. The results demonstrated that all of the autonomic indicators showed a general trend towards lower levels of arousal over time. The data also showed that three of the four muscle regions monitored--C4, T6, and L3 paraspinals--indicated a significant reduction in energy during and following the NCTT treatment sessions for a majority of the subjects. For example, the C4 EMG showed a significant NCTT treatment effect (F = 10.31; df = 1; p < .009 level), while the T6 EMG (F = 13.49; df = 1; p < .004) and L3 EMG (F = 4.74; df = 1; p < .05) also demonstrated significance. In addition to the habituation effects seen in the autonomic variables, the implications of neutralization of postural homeostasis and lowering of emotional arousal are discussed along with consideration of the Eastern concept of "nadis."

A peer-review system for monitoring pharmacists' practice in medication-refill clinics is described. Pharmacist practitioners trained in pharmacology, therapeutics, and physical assessment provide services in three medication-refill clinics associated with a 350-bed Department of Veterans Affairs (VA) medical center. The clinics serve patients who have exhausted their prescribed drugs before their next appointment with a physician. During a clinic visit, the pharmacist assesses the patient and the drug therapy and either consults an attending physician or writes new prescriptions. The pharmacist documents his or her activities in the medical record. The peer-review mechanism involves quarterly audits in which the chart notes written by the pharmacists are reviewed by other pharmacists. Five indicators of the quality of care are used in the peer reviews. The results are presented to the ambulatory-care and quality assurance pharmacy committees for analysis and discussion. The peer-review system has resulted in better compliance by the pharmacists with the quality indicators and clinic procedures, suggesting that the quality of care has also benefited. Peer review is used successfully to evaluate and monitor the care provided by pharmacists in medication-refill clinics associated with a VA medical center.

Purpose: To compare the sensitivity and specificity of an automated microparticle enzyme immunoassay (MEIA) for breast cancer mucin (IMx BCM; Abbott Laboratories, North Chicago, IL) to that of CA15-3 and carcinoembryonic antigen (CEA) for detecting and monitoring breast cancer., Materials and Methods: IMxBCM was compared to assays of CA15-3 and CEA in 630 serum specimens from healthy women, and from women with breast cancer, other malignancies, benign breast conditions, or other benign diseases., Results: Analysis of the log-transforms for the three markers in all specimens showed a high correlation of IMxBCM with CA15-3 (r = .78), but not with CEA (r = .25). Based on a receiver-operating-characteristics (ROC)-curve analysis for any given specificity, IMxBCM was found to be a more sensitive marker than either CA15-3 or CEA for distinguishing 105 women with advanced or metastatic breast cancer from 89 healthy women (P = .003 and P = .04, respectively), from 98 women with benign breast conditions (P = .02 and P = .002), or from 191 women with benign diseases (P = .03 and P less than .0001). At 95% specificity, the sensitivities of IMxBCM, CA15-3, and CEA for detecting advanced or metastatic breast cancer were 69%, 51%, and 30%, respectively. Serial serum samples (n = 177) were analyzed in 20 additional metastatic breast cancer patients with measurable disease. Serial IMxBCM levels corresponded with the clinical course of disease in 80%, CA15-3 in 65%, and CEA in 60% of the 20 patients., Conclusions: Increased sensitivity of IMxBCM, despite a high correlation with CA15-3, suggests that IMxBCM and CA15-3 may recognize distinct epitopes on the same molecule. Although further research is indicated, IMxBCM may provide a promising marker in the clinical management of breast cancer patients.

The relationship between surface EMG recordings from paraspinalis recording sites and subjective pain ratings were examined in a group of pre-chronic back pain patients. thirty-eight back pain patients without major orthopedic diagnosis and a pain duration between 2 to 6 months participated in a three week long subjective pain rating. Following the completion of their pain diary, the paraspinal sites were assessed under the "static" postural conditions of sitting and standing using an EMG scanning procedure. Results of the correlational analysis revealed significant and positive relationships between pain and muscle activity in the upper back (Trapezius, T1 paraspinalis sites) and significant but negative relationships between erector spinae activity (L3 paraspinalis site) and pain. When considering etiological factors of pre-chronic back pain, the results support both the organicity model for upper back, as well as the biomechanical model for the lower back.

As part of their evaluation, an EMG muscle scanning procedure was conducted on 100 patients enrolled in a pain program for in-patients. The left and right aspects of 11 muscle sites were monitored in the sitting and standing postures. Correlations between muscle region and average total muscle tension suggest that the lower and upper back muscles were the most highly related to their total tension. These results do not appear to be the results of statistical artifact and the correlations do not seem redundant. Further analyses identified the T10 paraspinals muscle site as most highly correlated with their total tension. These findings are preliminary and experiments are needed to confirm or repudiate the hypothesis that there is a key muscle. Investigators are encouraged to look to the back musculature for training generalized relaxation.

The reliability of a surface EMG scanning procedure was investigated for the right and left aspects of ten muscle sites using a large clinical sample of 102 chronic patients. Two neutral postures (sitting/standing) were systematically studied on three occasions approximately one hour apart on the same day. The multivariate analysis of RMS microvolts indicated no significant effects for Age, Gender, Muscle Site, Aspect, or Period. The range of the Pearson correlations was 0.41 to 0.94 when all muscle sites, aspects, postures, and periods were considered. The median correlation was found to be 0.64. The pattern of reliability was seen to be slightly higher in the lower back while standing. The results indicate that with adequate attention to skin preparation, EMG sensors held in place by hand with a light pressure produced reliable results.

The effects of eyelid position (open or closed) and three levels of room illumination on operant control of alpha EEG were investigated utilizing a factorial design. After base-line levels were determined, subjects were given alpha-contingent feedback and instructed to increase and decrease alpha production during six successive 4-min intervals. In addition, a comparison was made between percent time and average amplitude as dependent measures. The percent time data indicated that eyes-open training facilitated alpha enhancement and suppression. However, this was not supported by the average amplitude data. Ambient illumination, regardless of the measure utilized, facilitated alpha training, particularly when the eyes were open. These results are related to previous research and theoretical issues.

A surface EMG diagnostic protocol was developed to assess the neuromuscular/postural contributions to pain states. The EMG activity of the right and left aspects of 11 muscle groups were monitored while the patient was in the sitting and standing positions. The diagnostic protocol was evaluated by comparing the patterns of EMG activity in four diagnostic groups: headache only, neck/shoulder/upper back pain only, low back pain only, and mixed pain states. The results suggest that (1) bilateral levels of EMG activity in the frontalis and masseter groups are of primary importance for the headache patients, (2) the discrepancy between the right and left EMG activity in the lumbar and cervical paraspinal muscle groups are of primary importance for low back pain patients, (3) position (sit/stand) may provide important diagnostic information, and (4) the data appear to support the notion of a postural disturbance as a contributing factor in low back pain.

To examine the type of proprioceptive information which subjects include in the definition of tension, 52 subjects were asked to indicate the location of where they felt tension while engaging in a simple motor task. Responses indicated that tendon stretch, muscle tension, and other cues are utilized in the subject's definition of tension.

This study examined the correlation between EMG values measured with wide (25-1000 Hz) and narrow (100-200 Hz) band-width filters. An EMG diagnostic scan was conducted on 32 chronic pain patients admitted to an inpatient treatment unit. EMG readings were taken from a total of 44 sites (11 sites X 2 sides X 2 postures). Each EMG measure was passed in parallel through a narrow and wide band-pass filter and the stable readings were recorded. Correlated t tests and Pearson correlations were used to compare the data from the narrow and wide filter settings. The measures from the wide filter were significantly higher than the measures from the narrow filter. In addition, 61% of the correlations were greater than .90. The majority of the correlations below the median (.93) occurred in the neck region and the abdomen. The implications of the findings are discussed.

The purpose of this investigation was to determine whether headache activity information collected over the phone can be directly compared with headache activity information collected by systematic self-observation without jeopardizing internal validity because of calibration differences between the two measurement methods. A number of headache studies have relied on phone information for long-term follow-up data, while using systematic self-observation to collect all other data. Twenty-six headache sufferers participating in a tension headache study reported their headache activity over the phone and subsequently charted their headaches. Correlations were computed between the two measures. Results indicated that differences exist in the calibration of the two measurement methods. This seriously limits the conclusions of studies that used phone information to obtain follow-up data. Other recommendations concerning follow-up methodologies are discussed.

Surface electromyography provides a very valuable set of information when used diagnostically with pain-related disorders. Unfortunately, most researchers and clinicians limit their investigation to only one level of diagnostic information available concerning the neuromuscular system. This article develops and encourages the clinician/researcher to consider three levels of diagnostic information: emotional, organ-related, and postural aspects. The theoretical background and diagnostic procedures used to investigate each is presented. Differential treatment considerations, given differential diagnostic findings, are discussed.