Spine Intersegmental Flexion and Muscular Responses to Sudden Loading At the Hands Altered by Cognitive Dual-Tasking and Abdominal Bracing

Links

Abstract

Basic movement and muscle activation patterns greatly influence fundamental mechanisms of lumbar spine injury in response to sudden spine flexion perturbations. This thesis aims to explore the influence of cognitive dual-tasking and abdominal bracing on the kinematic and neuromuscular response of the spine and paraspinal musculature during studies 1 and 2, respectively. Neuromuscular control was assessed by delivering an unexpected perturbation to the hands of participants to induce sudden spine flexion. Study 1 employed cognitive dual-tasking through serial-7 subtraction while study 2 focused on abdominal bracing. Dual-tasking and bracing resulted in opposite kinematic responses where greater and lesser flexion occurred during the cognitive and bracing conditions, respectively. Dual-tasking caused delayed muscle onsets while bracing increased baseline activation in all abdominal muscles. These investigations highlight that cognitive loading and abdominal bracing can influence trunk muscle activation and reflex dynamics to modify spine motion in response to unexpected perturbations.

Cited Works (8)

Year	Entry
1992	Panjabi MM. The stabilizing system of the spine, II: neutral zone and instability hypothesis. J Spinal Disord. December 1992;5(4):390-396.
1949	Friberg S, Hirsch C. Anatomical and clinical studies on lumbar disc degeneration. Acta Orthop Scand. 1949;19(2):222-242.
1992	Crisco JJ, Panjabi MM, Yamamoto I, Oxland TR. Euler stability of the human ligamentous lumbar spine, II: experiment. Clin Biomech (Bristol, Avon). February 1992;7(1):27-32.
1996	Cholewicki J, McGill SM. Mechanical stability of the in vivo lumbar spine: implications for injury and chronic low back pain. Clin Biomech (Bristol, Avon). January 1996;11(1):1-15.
1992	Panjabi MM. The stabilizing system of the spine, I: function, dysfunction, adaptation, and enhancement. J Spinal Disord. December 1992;5(4):383-389.
1989	Bergmark A. Stability of the lumbar spine: a study in mechanical engineering. Acta Orthop Scand. 1989;60(suppl 230):1-54.
1997	McGill SM. The biomechanics of low back injury: implications on current practice in industry and the clinic. J Biomech. May 1997;30(5):465-475.
1991	McGill SM. Electromyographic activity of the abdominal and low back musculature during the generation of isometric and dynamic axial trunk torque: implications for lumbar mechanics. J Orthop Res. January 1991;9(1):91-103.