Design: Experimental study.
Setting: Institute of Clinical Anatomy and Biomechanics, the First Military Medical University, Guangzhou, China.
Subjects: Seven fresh cadaveric lumbar spines, from L1 to sacrum.
Interventions: Lumbar spines were loaded on a material test system, whose computer quantitative control simulated 3 manipulations. In state A, the lumbar spines were rotated only; in state B, the lumbar spines were simultaneously rotated and compressed; and in state C, the lumbar spines were simultaneously rotated and tractioned.
Main Outcome Measures: Pressures of the lumbar nucleus pulposus of L3-4, L4-5, L5-S1 were measured with pressure sensors.
Result: Lumbar nuclear pressure for rotation manipulation and compression-rotation manipulation was apparently increased, and the pressures of lumbar nucleus pulposus for traction-rotatory manipulation were reduced or slightly changed.
Conclusions: The results of this preliminary research suggest that rotary manipulation of lumbar spine under traction created the lowest pressures and was theoretically the safest of the 3 procedures.
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