Neurophysiologic effects of spinal manipulation in patients with chronic low back pain

<p>Abstract</p> <p>Background</p> <p>While there is growing evidence for the efficacy of SM to treat LBP, little is known on the mechanisms and physiologic effects of these treatments. Accordingly, the purpose of this study was to determine whether SM alters the amplitude of the motor evoked potential (MEP) or the short-latency stretch reflex of the erector spinae muscles, and whether these physiologic responses depend on whether SM causes an audible joint sound.</p> <p>Methods</p> <p>We used transcranial magnetic stimulation to elicit MEPs and electromechanical tapping to elicit short-latency stretch reflexes in 10 patients with chronic LBP and 10 asymptomatic controls. Neurophysiologic outcomes were measured before and after SM. Changes in MEP and stretch reflex amplitude were examined based on patient grouping (LBP vs. controls), and whether SM caused an audible joint sound.</p> <p>Results</p> <p>SM did not alter the erector spinae MEP amplitude in patients with LBP (0.80 ± 0.33 vs. 0.80 ± 0.30 μV) or in asymptomatic controls (0.56 ± 0.09 vs. 0.57 ± 0.06 μV). Similarly, SM did not alter the erector spinae stretch reflex amplitude in patients with LBP (0.66 ± 0.12 vs. 0.66 ± 0.15 μV) or in asymptomatic controls (0.60 ± 0.09 vs. 0.55 ± 0.08 μV). Interestingly, study participants exhibiting an audible response exhibited a 20% decrease in the stretch reflex (p < 0.05).</p> <p>Conclusions</p> <p>These findings suggest that a single SM treatment does not systematically alter corticospinal or stretch reflex excitability of the erector spinae muscles (when assessed ~ 10-minutes following SM); however, they do indicate that the stretch reflex is attenuated when SM causes an audible response. This finding provides insight into the mechanisms of SM, and suggests that SM that produces an audible response may mechanistically act to decrease the sensitivity of the muscle spindles and/or the various segmental sites of the Ia reflex pathway.</p

Test-retest repeatability of strength capacity, aerobic power and pericranial tenderness of neck and shoulder muscles in children - relevant for tension-type headache

Birte Torn&oslash;e,1,2,5,6 Lars L Andersen,3 J&oslash;rgen H Skotte,3 Rigmor Jensen,4 Gunvor Gard,1 Liselotte Skov,2 Inger Hallstr&ouml;m1 1Department of Health Sciences, Lund University, Scania, Sweden; 2Children&#39;s Headache Clinic, Department of Pediatrics, University of Copenhagen, Herlev Hospital, Herlev, Denmark; 3National Research Centre for the Working Environment, Copenhagen, Denmark; 4Danish Headache Center, Department of Neurology, University of Copenhagen, Glostrup Hospital, Glostrup, Denmark; 5Department of Physiotherapy and Occupational Therapy, University of Copenhagen, Glostrup Hospital, Glostrup, Denmark; 6Department of Physiotherapy, Medical Department, University of Copenhagen, Herlev Hospital, Herlev, Denmark Background: Frequent or chronic tension-type headache in children is a prevalent and debilitating condition for the child, often leading to medication overuse. To explore the relationship between physical factors and tension-type headache in children, the quality of repeated measures was examined. The aim of the present study was to determine the test-retest repeatability of parameters determining isometric neck and shoulder strength and stability, aerobic power, and pericranial tenderness in children. Methods: Twenty-five healthy children, 9 to 18 years of age, participated in test-retest procedures within a 1-week interval. A computerized padded force transducer was used for testing. The tests included the isometric maximal voluntary contraction and force steadiness of neck flexion and extension, and the isometric maximal voluntary contraction and rate of force of the dominant shoulder. Pericranial tenderness was recorded by means of standardized manual palpation, and a submaximal cycle ergometer test predicted maximal oxygen uptake (VO2 max). The measurements were evaluated in steps, using the intraclass correlation coefficient (ICC); changes in the mean between the two test occasions; the levels of agreement, visualized in Bland-Altman Plots; and by quantifying the variability. Results: The results showed an acceptable test-retest repeatability of isometric maximal voluntary contraction (ICC 0.90-0.97). The force steadiness measurements revealed a trend of systematic changes in the direction of neck flexion and need further examination in both healthy and ill children. The rate of force development, Total Tenderness Score, and prediction of VO2 max showed repeatability, with ICC 0.80-0.87. Conclusion: The measurements of strength capacity, aerobic power, and tenderness provide acceptable repeatability, suitable for research in children. Keywords: muscle strength, intratester reliability, cardiovascular fitnes

Specific strength training compared with interdisciplinary counseling for girls with tension-type headache: a randomized controlled trial

Birte Torn&oslash;e,1&ndash;4 Lars L Andersen,5,6 J&oslash;rgen H Skotte,5 Rigmor Jensen,7 Claus Jensen,8 Bjarne K Madsen,7 Gunvor Gard,1 Liselotte Skov,2 Inger Hallstr&ouml;m,11Department of Health Sciences, Lund University, Lund, Sweden; 2Department of Pediatrics E, Children&rsquo;s Headache Clinic, University of Copenhagen, Herlev and Gentofte Hospitals, Copenhagen, Denmark; 3Department of Physiotherapy and Occupational Therapy, University of Copenhagen, Glostrup Hospital, Copenhagen, Denmark; 4Department of Physiotherapy, University of Copenhagen, Herlev and Gentofte Hospitals, Copenhagen, Denmark; 5National Research Centre for the Working Environment, Copenhagen, Denmark; 6Physical Activity and Human Performance group, SMI, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark; 7Department of Neurology, Danish Headache Centre, University of Copenhagen, Glostrup Hospital, Copenhagen, Denmark; 8Huge Consulting, ApS, Haslev, Denmark Background: Childhood tension-type headache (TTH) is a prevalent and debilitating condition for the child and family. Low-cost nonpharmacological treatments are usually the first choice of professionals and parents. This study examined the outcomes of specific strength training for girls with TTH. Methods: Forty-nine girls aged 9&ndash;18 years with TTH were randomized to patient education programs with 10 weeks of strength training and compared with those who were counseled by a nurse and physical therapist. Primary outcomes were headache frequency, intensity, and duration; secondary outcomes were neck&ndash;shoulder muscle strength, aerobic power, and pericranial tenderness, measured at baseline, after 10 weeks intervention, and at 12 weeks follow-up. Health-related quality of life (HRQOL) questionnaires were assessed at baseline and after 24 months. Results: For both groups, headache frequency decreased significantly, P=0.001, as did duration, P=0.022, with no significant between-group differences. The odds of having headache on a random day decreased over the 22 weeks by 0.65 (0.50&ndash;0.84) (odds ratio [95% confidence interval]). For both groups, neck extension strength decreased significantly with a decrease in cervicothoracic extension/flexion ratio to 1.7, indicating a positive change in muscle balance. In the training group, shoulder strength increased &ge;10% in 5/20 girls and predicted VO2max increased &ge;15% for 4/20 girls. In the training group, 50% of girls with a headache reduction of &ge;30% had an increase in VO2max &gt;5%. For the counseling group, this was the case for 29%. A 24-month follow-up on HRQOL for the pooled sample revealed statistically significant improvements. Fifty-five percent of the girls reported little to none disability. Conclusion: The results indicate that both physical health and HRQOL can be influenced significantly by physical exercise and nurse counseling. More research is needed to examine the relationship between physical exercise, VO2max, and TTH in girls. Thus, empowering patient education to promote maximum possible outcomes for all children needs more attention. Keywords: empowering patient education, neck and shoulder muscles, muscular fitness, cardiovascular fitness, headache, child, health and physical therapy&nbsp