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Updated: Aug 14, 2026
09:24
A Novel Vertebral Stabilization Method for Producing Contusive Spinal Cord Injury
Published on: January 5, 2015
Spinal manipulation force and duration affect vertebral movement and neuromuscular responses
Christopher J Colloca1, Tony S Keller, Deed E Harrison
1Biomechanics Laboratory, Exercise and Sport Research Institute, Department of Kinesiology, Arizona State University, Tempe, AZ, USA. cjcolloca@neuromechanical.com
Clinical Biomechanics (Bristol, Avon)
|December 28, 2005
Summary
Spinal manipulative thrusts affect ovine lumbar spine biomechanics and neuromuscular responses. Varying thrust force and duration alters vertebral displacement and muscle activation, offering insights into clinical outcomes.
Area of Science:
- Biomechanical research
- Neuromuscular physiology
- Spinal manipulation studies
Background:
- Human studies document responses to spinal manipulative thrusts.
- Limited understanding of how varying thrust force-time profiles impact neuromechanical responses.
Purpose of the Study:
- To investigate the neuromechanical effects of varying spinal manipulative thrust force-time profiles.
- To examine lumbar motion and multifidus electromyographic responses in an ovine model.
Main Methods:
- Anesthetized adolescent Merino sheep underwent posteroanterior mechanical thrusts at L3.
- Variable pulse durations (10-200 ms) and force amplitudes (20-80 N) were applied.
- Lumbar motion (L3 displacement, L1/L2 acceleration) and multifidus EMG were measured.
Main Results:
- Increased force amplitude linearly increased L3 displacement and L1/L2 acceleration.
- Shorter thrust durations (10 ms) significantly reduced L3 displacement and increased L2 acceleration.
- Electromyographic responses showed linear increases with force and were influenced by pulse duration.
Conclusions:
- Altered biomechanical and neuromuscular responses were observed with changes in thrust force-time characteristics.
- These findings may elucidate underlying mechanisms for clinical outcomes in spinal manipulation.
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