The relation between the transversus abdominis muscles, sacroilac joint mechanics, and low back pain

Study Design. Two abdominal muscle patterns were tested in the same group of individuals, and their effects were compared in relation to sacroiliac joint laxity. One pattern was contraction of the transversus abdominis, Independently of the other abdominals; the other was a bracing action that used all the lateral abdominal muscles. Objectives. To demonstrate the biomechanical effect of the exercise for the transversus abdominis known to be effective in low back pain. Summary of Background Data. Drawing in the abdominal wall is a specific exercise for the transversus abdominis muscle (in cocontraction with the multifidus), which is used in the treatment of back pain. Clinical effectiveness has been demonstrated to be a reduction of 3-year recurrence from 75% to 35%. To the authors' best knowledge, there is not yet in vivo proof of the biomechanical effect of this specific exercise. This study of a biomechanical model on the mechanics of the sacroiliac joint, however, predicted a significant effect of transversus abdominis muscle force. Methods. Thirteen healthy individuals who could perform the test patterns were included. Sacroiliac joint laxity values were recorded with study participants in the prone position during the two abdominal muscle patterns. The values were recorded by means of Doppler Imaging of vibrations. Simultaneous electromyographic recordings and ultrasound imaging were used to verify the two muscle patterns. Results. The range of sacroiliac joint laxity values observed in this study was comparable with levels found in earlier studies of healthy individuals. These values decreased significantly in all individuals during both muscle patterns (P < 0.001). The independent transversus abdominis contraction decreased sacroiliac joint laxity (or rather increased sacroiliac joint stiffness) to a significantly greater degree than the general abdominal exercise pat-tern (P < 0.0260). Conclusions. Contraction of the transversus abdominis significantly decreases the laxity of the sacroiliac joint. This decrease in laxity is larger than that caused by a bracing action using all the lateral abdominal muscles. These findings are in line with the authors' biomechanical model predictions and support the use of independent transversus abdominis contractions for the treatment of low back pain.

The effect of soft tissue deloading tape on thoracic spine pressure pain thresholds in asymptomatic subjects

The application of tape to deload soft tissue is used in the management of thoracic spine pain. A reported clinical feature of this treatment is reduced tenderness of the spine during postero-anterior mobilizations. A randomized, single blind, placebo controlled, repeated measures design study was employed to investigate the effects of deloading tape on pressure pain threshold measurements at the level of the T7 spinous process in an asymptomatic group of 24 subjects. Pressure pain thresholds were assessed prior to and following the application of deloading tape, placebo sham tape and no-tape control conditions. All subjects received all three conditions in a randomized order on three separate days. Differences between the pre- and post-measurements were used as indicators of change in a subject's pressure pain threshold. No significant change in pressure pain threshold measurements was found between conditions. In summary, this study demonstrated that deloading tape applied to the level of the T7 spinous process did not significantly change pressure pain threshold measurements in asymptomatic subjects, raising the possibility that any pain relieving effect may well be conditional upon pain being present. (C) 2002 Elsevier Science Ltd. All rights reserved.

Barriers to effective cancer pain management: A survey of hospitalized cancer patients in Australia

The purpose of this study was to examine attitudinal barriers to effective pain management in a consecutively recruited cohort of 114 cancer patients from four Australian hospitals. When surveyed, 48% of this sample reported experiencing pain within the previous 24 hours. Of these, 56% reported this pain to be distressing, horrible or excruciating, with large proportions indicating that this pain had affected their movement, sleep and emotional well-being. Three factors were identified as potentially impacting on patients responses to pain-poor levels of patient knowledge about pain, low perceived control over pain, and a deficit in communication about pain. A trend for older patients to experience more severe pain was also identified. These older patients reported being more willing to tolerate pain and perceive less control over their pain. Suggestions are made for developing patient education programs and farther research using concepts drawn from broader social and behavioral models. J Pain Symptom Manage 2002:23:393-405. (C) U.S. Cancer Pain Relief Committee, 2002.

Affective and evaluative descriptors of pain in the McGill Pain Questionnaire: reduction and reorganization

Recent reports indicate that several descriptors of pain sensations in the McGill Pain Questionnaire (MPQ) are difficult to classify within MPQ sensory subcategories because of incomprehension, underuse, or ambiguity of usage. Adopting the same methodology of recent studies, the present investigation focused on the affective and evaluative subcategories of the MPQ. A decision rule revealed that only 6 of 18 words met criteria for the affective category and 5 of 11 words met criteria for the evaluative category, thus warranting a reduced list of words in these categories. This reduction, however, led to negligible loss of information transmitted. Despite notable changes in classification, the intensity ratings of the retained words correlated very highly with those originally reported for the MPQ. In conclusion, although the intensity ratings of MPQ affective and evaluative descriptors need no revision, selective reduction and reorganization of these descriptors can enhance the efficiency of this approach to pain assessment. [copy ] 2001 by the American Pain Society

Dimensionality and clinical importance of pain and disability in hand osteoarthritis: Development of the Australian/Canadian (AUSCAN) Osteoarthritis Hand Index

Objective: To develop a reliable, valid, and responsive self-administered questionnaire to probe pain, stiffness and physical disability in patients with osteoarthritis (OA) of the hand. Design: In order to assess the dimensionality of the symptomatology of hand OA, a self-administered questionnaire was developed to probe various aspects of pain (10 items), stiffness (two items), and physical function (83 items). The question inventory was generated from eight existing health status measures and an interactive process involving four rheumatologists, two physiotherapists, and an orthopaedic surgeon. Results: Face-to-face interviews were conducted with 50 OA hand patients; 39 females and 11 males with mean age 62.8 years and mean disease duration 9.4 years. Items retained were those which fulfilled specified selection criteria: prevalence greater than or equal to60% and mean importance score approximating or exceeding 2.0 Item exclusion criteria included low prevalence, gender-based, ambiguous, duplicates or similarities, alternatives, composite items, and items that were too restrictive. This process resulted in five pain, one stiffness and nine function items which have been proposed for incorporation in the AUSCAN Index. Conclusions: Using a traditional development strategy, we have constructed a self-administered multi-dimensional outcome measure for assessing hand OA. The next stage includes reliability, validity and responsiveness testing of the 15-item questionnaire. (C) 2002 OsteoArthritis Research Society Intenational. Published by Elsevier Science Ltd. All rights reserved.

Rhythmic variations in pain, stiffness, and manual dexterity in hand osteoarthritis

Objective: To explore circadian variation in pain, stiffness, and manual dexterity inpatients with hand osteoarthritis (OA). Methods: Twenty one patients with hand OA, as defined by ACR criteria (17 women, four men, mean age 62.2 years, range 52-74 years) self rated pain and stiffness on separate 10 cm horizontal visual analogue scales and performed bead intubation coordinometry (BIC) six times each day (on waking up, at bedtime, and every four hours in between) for 10 consecutive days. Each series (using data with the trend removed if there was a significant trend) was analysed for circadian rhythmicity by a cosine. vector technique (single cosinor). With individual data expressed as the percentage of the mean, group rhythm characteristics at period 24 hours were summarised for each variable by population mean cosinor analysis. Results: Individual analyses identified significant circadian rhythms at pless than or equal to0.05 for pain (n=15/21), stiffness (n=16/20), and dexterity (n=18/21), and a significant circadian rhythm on a group basis was identified for pain (p=0.013), stiffness (p

Exercise-induced alterations in neutrophil degranulation and respiratory burst activity: possible mechanisms of action

Neutrophils constitute 50-60% of all circulating leukocytes; they present the first line of microbicidal defense and are involved in inflammatory responses. To examine immunocompetence in athletes, numerous studies have investigated the effects of exercise on the number of circulating neutrophils and their response to stimulation by chemotactic stimuli and activating factors. Exercise causes a biphasic increase in the number of neutrophils in the blood, arising from increases in catecholamine and cortisol concentrations. Moderate intensity exercise may enhance neutrophil respiratory burst activity, possibly through increases in the concentrations of growth hormone and the inflammatory cytokine IL-6. In contrast, intense or long duration exercise may suppress neutrophil degranulation and the production of reactive oxidants via elevated circulating concentrations of epinephrine (adrenaline) and cortisol. There is evidence of neutrophil degranulation and activation of the respiratory burst following exercise-induced muscle damage. In principle, improved responsiveness of neutrophils to stimulation following exercise of moderate intensity could mean that individuals participating in moderate exercise may have improved resistance to infection. Conversely, competitive athletes undertaking regular intense exercise may be at greater risk of contracting illness. However there are limited data to support this concept. To elucidate the cellular mechanisms involved in the neutrophil responses to exercise, researchers have examined changes in the expression of cell membrane receptors, the production and release of reactive oxidants and more recently, calcium signaling. The investigation of possible modifications of other signal transduction events following exercise has not been possible because of current methodological limitations. At present, variation in exercise-induced alterations in neutrophil function appears to be due to differences in exercise protocols, training status, sampling points and laboratory assay techniques.

Endogenous endothelin-1 limits exercise-induced vasodilation in hypertensive humans

Essential hypertension is a common disorder, associated with increased endothelin-l-mediated vasoconstrictor tone at rest. We hypothesized that increased vasoconstrictor activity of endothelin-1 might explain why the normal decrease in peripheral vascular resistance in response to exercise is attenuated in hypertensive patients. Therefore, we investigated the effect of endothelin A (ETA) receptor blockade on the vasodilator response to handgrip exercise. Forearm blood flow responses to handgrip exercise (15%, 30%, and 45% of maximum voluntary contraction) were assessed in hypertensive patients and matched normotensive subjects, before and after intra-arterial infusions of the ETA receptor antagonist BQ-123; a control dilator, hydralazine; and placebo (saline). Preinfusion (baseline) vasodilation in response to exercise was significantly attenuated at each workload in hypertensive patients compared with normotensive subjects. Intra-arterial infusions of hydralazine and saline did not increase the vasodilator response to exercise in either hypertensives or normotensives at any workload. The vasodilator response to exercise was markedly enhanced after BQ-123 at the 2 higher workloads in hypertensives (157 +/- 48%, P < 0.01; 203 &PLUSMN; 58%, P < 0.01) but not in normotensives. This suggests that the impaired vasodilator response to exercise in hypertensive patients is, at least in part, a functional limitation caused by endogenous ETA receptor-mediated vasoconstriction. Treatment with endothelin receptor antagonists may, therefore, increase exercise capacity in essential hypertension.

Therapeutic patellar taping changes the timing of vasti muscle activation in people with patellofemoral pain syndrome

Objective: To examine the effect of the application of tape over the patella on the onset of electromyographic (EMG) activity of vastus medialis obliquus (VMO) relative to vastus lateralis (VL) in participants with and without patellofemoral pain syndrome (PFPS). Design: Randomised within subject. Settings: University laboratory. Participants: Ten participants with PFPS and 12 asymptomatic controls. Interventions: Three experimental taping conditions: no tape, therapeutic tape, and placebo tape. Main Outcome Measures: Electromyographic onset of VMO and VL assessed during the concentric and eccentric phases of a stair stepping task. Results: When participants with PFPS completed the stair stepping task, the application of therapeutic patellar tape was found to alter the temporal characteristics of VMO and VL activation, whereas placebo tape had no effect. In contrast, there was no change in the EMG onset of VMO and VL with the application of placebo or therapeutic tape to the knee in the asymptomatic participants. Conclusions: These data support the use of patellar taping as an adjunct to rehabilitation in people with PFPS.

Cisplatin-induced ototoxicity and pharmacokinetics: Preliminary findings in a dog model

The early effects of clinical dose of cisplatin (100 mg/m(2)) on distort ion-product otoacoustic emissions (DPOAE) thresholds and the relationship between DPOAE threshold shifts and changes in plasma concentrations of filterable and total platinum (Pt) following infusion of cisplatin in a dog model were investigated. The DPOAE thresholds (based on input-output function) were measured 2 days before a single high dose of cisplatin administration, and compared with measurements recorded 2 and 4 days after infusion. The results revealed DPOAE thresholds to be elevated by 4 days after the administration of cisplatin. However, this elevation could not be correlated with plasma concentrations of filterable and total Pt, which showed little variation over the 48-hour postinfusion period between animals. The present study demonstrated that DPOAE thresholds have the potential to be used as an indicator of cisplatin-induced ototoxicity, and cisplatin-induced ototoxicity could not be explained by plasma Pt kinetics in individual animals.

Arsenic inhibits the repair of DNA damage induced by benzo(a)pyrene

In order to study the effect of arsenic on DNA damage, Sprague-Dawley rats were dosed with sodium arsenite (10 mg/kg) with or without 800 mug of benzo(a)pyrene (BP) by intramammilary injection. The animals were sacrificed on day 1, 3, 5, 10 and 27 and the mammary gland tissues were collected for DNA adduct measurement using a P-32 post-labeling assay. Animals dosed with arsenic alone did not show any DNA adducts. DNA adduct levels in rats dosed with BP alone reached a maximum level by day 5, reducing to 13% of this level by day 27. Adduct levels in rats dosed with arsenic and BP also reached a maximum by day 5 but only 80% of the level observed in the BP group. However, 84% of this amount still remained by day 27. The First Nucleotide Change (FNC) technique was used for the screening of 115 samples of various tissues from mice that had been chronically exposed to sodium arsenate for over 2 years revealed that inorganic arsenic did not attack the two putative hotspots (codons 131 and 154) of the hOGG1 gene. These results support the hypothesis that arsenic exerts its biological activity through DNA repair inhibition. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.

Relationship between stress-induced martensitic transformation and impact toughness in low carbon austenitic steels

The effect of test temperature, which controls the stability of austenite, on the impact toughness of a low carbon Fe-Ni-Mn-C austenitic steel and 304 stainless steel, has been investigated. Under impact conditions, stress-induced martensitic transformation occurred, in a region near the fracture surface, at test temperatures below 80degreesC for the Fe-Ni-Mn-C steel and below -25degreesC for 304 stainless steel. The former shows significant transformation toughening and the highest impact toughness was obtained at 10degreesC, which corresponds to the maximum amount of martensite formed by stress-induced transformation above the Ms temperature. The stress-induced martensitic transformation contributes negatively to the impact toughness in the 304 stainless steel. Increasing the amount of stress-induced transformation to martensite, lowered the impact toughness. The experimental results can be well explained by the Antolovich theory through the analysis of metallography and fractography. The different effect of stress-induced transformation on the impact toughness in Fe-Ni-Mn-C steel and 304 stainless steel has been further understood by applying the crystallographic model for stress-induced martensitic transformation to these two steels. (C) 2002 Kluwer Academic Publishers.

Combined physiotherapy and education is efficacious for chronic low back pain

Manual therapy, exercise and education target distinct aspects of chronic low back pain and probably have distinct effects, This study aimed to determine the efficacy of a combined physiotherapy treatment that comprised all of these strategies. By concealed randomisation, 57 chronic low back pain patients were allocated to either the four-week physiotherapy program or management as directed by their general practitioners, The dependent variables of interest were pain and disability. Assessors were blind to treatment group. Outcome data from 49 subjects (86%) showed a significant treatment effect. The physiotherapy program reduced pain and disability by a mean of 1.5/10 points on a numerical rating scale (95% CI 0.7 to 2.3) and 3.9 points on the 18-point Roland Morris Disability Questionnaire (95% CI 2 to 5.8), respectively. The number needed to treat in order to gain a clinically meaningful change was 3 (95% CI 3 to 8) for pain, and 2 (95% CI 2 to 5) for disability. A treatment effect was maintained at one-year follow-up. The findings support the efficacy of combined physiotherapy treatment in producing symptomatic and functional change in moderately disabled chronic low back pain patients.