Biomedical subjects

Debra Shirley

Publications and source records attributed to Debra Shirley.

4 recordsLinked to original sources

PubMed2005

Intra-abdominal pressure increases stiffness of the lumbar spine.

Intra-abdominal pressure (IAP) increases during many tasks and has been argued to increase stability and stiffness of the spine. Although several studies have shown a relationship between the IAP increase and spinal stability, it has been impossible to determine whether this augmentation of mechanical support for the spine is due to the increase in IAP or the abdominal muscle activity which contributes to it. The present study determined whether spinal stiffness increased when IAP increased without concurrent activity of the abdominal and back extensor muscles. A sustained increase in IAP was evoked by tetanic stimulation of the phrenic nerves either unilaterally or bilaterally at 20 Hz (for 5 s) via percutaneous electrodes in three subjects. Spinal stiffness was measured as the force required to displace an indentor over the L4 or L2 spinous process with the subjects lying prone. Stiffness was measured as the slope of the regression line fitted to the linear region of the force-displacement curve. Tetanic stimulation of the diaphragm increased IAP by 27-61% of a maximal voluntary pressure increase and increased the stiffness of the spine by 8-31% of resting levels. The increase in spinal stiffness was positively correlated with the size of the IAP increase. IAP increased stiffness at L2 and L4 level. The results of this study provide evidence that the stiffness of the lumbar spine is increased when IAP is elevated.

Abdomen↗

PubMed2002

A randomized controlled trial of exercise and manipulative therapy for cervicogenic headache.

STUDY DESIGN: A multicenter, randomized controlled trial with unblinded treatment and blinded outcome assessment was conducted. The treatment period was 6 weeks with follow-up assessment after treatment, then at 3, 6, and 12 months. OBJECTIVES: To determine the effectiveness of manipulative therapy and a low-load exercise program for cervicogenic headache when used alone and in combination, as compared with a control group. SUMMARY OF BACKGROUND DATA: Headaches arising from cervical musculoskeletal disorders are common. Conservative therapies are recommended as the first treatment of choice. Evidence for the effectiveness of manipulative therapy is inconclusive and available only for the short term. There is no evidence for exercise, and no study has investigated the effect of combined therapies for cervicogenic headache. METHODS: In this study, 200 participants who met the diagnostic criteria for cervicogenic headache were randomized into four groups: manipulative therapy group, exercise therapy group, combined therapy group, and a control group. The primary outcome was a change in headache frequency. Other outcomes included changes in headache intensity and duration, the Northwick Park Neck Pain Index, medication intake, and patient satisfaction. Physical outcomes included pain on neck movement, upper cervical joint tenderness, a craniocervical flexion muscle test, and a photographic measure of posture. RESULTS: There were no differences in headache-related and demographic characteristics between the groups at baseline. The loss to follow-up evaluation was 3.5%. At the 12-month follow-up assessment, both manipulative therapy and specific exercise had significantly reduced headache frequency and intensity, and the neck pain and effects were maintained (P < 0.05 for all). The combined therapies was not significantly superior to either therapy alone, but 10% more patients gained relief with the combination. Effect sizes were at least moderate and clinically relevant. CONCLUSION: Manipulative therapy and exercise can reduce the symptoms of cervicogenic headache, and the effects are maintained.

Adult↗

PubMed2002

Professional responsibility in relation to cervical spine manipulation.

Manipulation of the cervical spine is one of the few potentially life-threatening procedures performed by physiotherapists. Is it worth the risk? A comparison of risks versus benefits indicates that at present, the risks of cervical manipulation outweigh the benefits: manipulation has yet to be shown to be more effective for neck pain and headache than other interventions such as mobilisation, whereas the risks, although infrequent, are serious. This analysis is of particular concern because the conditions for which manipulation is indicated are benign and usually self-limiting. Because physiotherapists have legal and ethical obligations to the community to avoid foreseeable harm and provide optimum care, it may be prudent to determine who in our profession should perform cervical manipulation. That is, the profession could restrict the practice of cervical spine manipulation. Although all registered physiotherapists in Australia are entitled to perform cervical manipulation, few choose to use this intervention. Therefore, it might be feasible to encourage those practitioners who wish to use cervical manipulation to undertake formal education programs. Such a requirement could be embodied in a code of practice that discourages those without formal training from performing cervical manipulation. By taking such measures, we could ensure that our profession exercises wisdom in its monitoring and use of cervical manipulation.

Australia↗

PubMed1997

Inter-examiner reliability to detect painful upper cervical joint dysfunction.

The presence of painful upper cervical joint dysfunction is a diagnostic criterion for cervicogenic headache. This preliminary study investigated whether independent examiners for a planned multicentre study of treatment of cervicogenic headache sufferers would agree on the presence or not of joint dysfunction for inclusion/exclusion of subjects into the trial. Ten subjects with or without neck pain and headache were recruited in each of four centres (total 40 subjects). Examiners manually assessed subjects' upper cervical regions in a single blind manner. There was excellent to complete agreement between each pair of examiners on which subjects should be allowed to enter the study and 70 per cent agreement between examiners on the two most dysfunctional joints in symptomatic subjects. There can be confidence that an homogenous headache group will enter the planned trial.

Journal Article↗