In vivo measurement of the effect of intra-abdominal pressure on the human spine

Hodges, P. W., Cresswell, A. G., Daggfeldt, K. and Thorstensson, A. (2001) In vivo measurement of the effect of intra-abdominal pressure on the human spine. Journal of Biomechanics, 34 3: 347-353. doi:10.1016/S0021-9290(00)00206-2

Author Hodges, P. W.
Cresswell, A. G.
Daggfeldt, K.
Thorstensson, A.
Title In vivo measurement of the effect of intra-abdominal pressure on the human spine
Journal name Journal of Biomechanics   Check publisher's open access policy
ISSN 0021-9290
Publication date 2001-01-01
Year available 2001
Sub-type Article (original research)
DOI 10.1016/S0021-9290(00)00206-2
Open Access Status DOI
Volume 34
Issue 3
Start page 347
End page 353
Total pages 7
Place of publication Oxford
Publisher Elsevier Sci Ltd
Language eng
Subject 321024 Rehabilitation and Therapy - Occupational and Physical
110601 Biomechanics
110603 Motor Control
Abstract In humans, intra-abdominal pressure (IAP) is elevated during many everyday activities. This experiment aimed to investigate the extent to which increased IAP-without concurrent activity of the abdominal or back extensor muscles-produces an extensor torque. With subjects positioned in side lying on a swivel table with its axis at L3, moments about this vertebral level were measured when IAP was transiently increased by electrical stimulation of the diaphragm via the phrenic nerve. There was no electromyographic activity in abdominal and back extensor muscles. When IAP was increased artificially to similar to 15% of the maximum IAP amplitude that could be generated voluntarily with the trunk positioned in flexion, a trunk extensor moment (similar to6 Nm) was recorded. The size of the effect was proportional to the increase in pressure. The extensor moment was consistent with that predicted from a model based on measurements of abdominal cross-sectional area and IAP moment arm. When IAP was momentarily increased while the trunk was flexed passively at a constant velocity, the external torque required to maintain the velocity was increased. These results provide the first in vivo data of the amplitude of extensor moment that is produced by increased IAP. Although the net effect of this extensor torque in functional tasks would be dependent on the muscles used to increase the IAP and their associated flexion torque, the data do provide evidence that IAP contributes, at least in part, to spinal stability. (C) 2001 Elsevier Science Ltd. All rights reserved.
Keyword Biophysics
Engineering, Biomedical
Abdominal Muscles
Postural Control
Trunk Muscle-activity
Intraabdominal Pressure
Lumbar Spine
Human Diaphragm
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status Unknown

Document type: Journal Article
Sub-type: Article (original research)
Collections: School of Health and Rehabilitation Sciences Publications
School of Human Movement and Nutrition Sciences Publications
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 85 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 105 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Mon, 13 Aug 2007, 22:14:32 EST