Date of Award
Open Access Thesis
Medical Doctor (MD)
Manohar M Panjabi MD
The purpose of this study is to quantify the dynamic mechanical properties of human cervical ligaments following whiplash. Cervical ligaments function to provide spinal stability, propioception, and protection during traumatic events to the spine. The function of cervical ligaments is largely dependant on their dynamic biomechanical properties, which include force and energy resistance, elongation capability, and stiffness. Whiplash has been shown to injure human cervical spine ligaments, and ligamental injury has been shown to alter their dynamic properties, with potential clinical consequences such as joint degeneration and pain. In this study we quantified the dynamic properties of human lower cervical ligaments following whiplash and compared their properties to those of intact ligaments. Whiplash simulation was performed using biofidelic whole cervical spine with muscle force replication (WCS-MFR) models. Next, ligaments were elongated to failure at a fast elongation rate and peak force, peak elongation, peak energy, and stiffness values were calculated from non-linear force-elongation curves. Peak force was highest in the ligamentum flavum (LF) and lowest in the intraspinous and supraspinous ligaments (ISL+SSL). Elongation was smallest in middle-third disc (MTD) and greatest in ISL+SSL. Highest peak energy was found in capsular ligament (CL) and lowest in MTD. LF was the stiffest ligament and ISL+SSL least stiff. These findings were similar to those found in intact ligaments. When directly comparing ligaments following whiplash to intact ligaments in a prior study it was found that the anterior longitudinal ligament (ALL) and CL had altered dynamic properties that were statistically significant, suggesting that whiplash may alter the dynamic properties of cervical ligaments. These findings may contribute to the understanding of whiplash injuries and the development of mathematical models simulating spinal injury.
Valenson, A.J., "Dynamic Mechanical Properties of Human Cervical Spine Ligaments Following Whiplash" (2007). Yale Medicine Thesis Digital Library. 298.