19 Harley St, London, W1G 9QJ, UK
We are London's Top Spine Clinic

Compressive follower load influences cervical spine kinematics and kinetics during simulated head-first impact in an ex vivo model.

Compressive follower load influences cervical spine kinematics and kinetics during simulated head-first impact in an ex vivo model.

J Biomech Eng. 2013 Jun 1;

Authors: Cripton PA, Saari A, Dennison CR, Zhu Q, Nelson TS, Morley P, Itshayek E, Oxland TR

Current understanding of the biomechanics of cervical spine injuries in head first impact is based on decades of epidemiology, mathematical models and on ex vivo experimental studies. Recent mathematical modeling suggests that muscle activation and muscle forces influence injury risk and mechanics in head first impact. It is also known that muscle forces are central to the overall physiologic stability of the cervical spine. Despite this knowledge, the vast majority of ex vivo head first impact models do not incorporate musculature. We hypothesize that the simulation of the stabilizing mechanisms of musculature during head first osteoligamentous cervical spine experiments will influence the resulting kinematics and injury mechanisms. Therefore, the objective of this study was to document differences in the kinematics, kinetics and injuries of ex-vivo osteoligamentous human cervical spine and surrogate head complexes that were instrumented with simulated musculature relative to specimens that were not instrumented with musculature. We simulated head first impact (3 m/s impact speed) using cervical spines and surrogate head specimens (n=12). Six spines were instrumented with a follower load to simulate in vivo compressive muscle forces, while six were not. The principal finding was that the axial coupling of the cervical column between the head and the base of the cervical spine (T1) was increased in specimens with follower load. Increased axial coupling was indicated by significantly reduced time between head impact and peak neck reaction force (p=0.004) (and time to injury (p=0.009)), in complexes with follower load relative to complexes without follower load. Kinematic reconstruction of vertebral motions indicated that all specimens experienced hyperextension and the spectrum of injuries in all specimens were consistent with a primary hyperextension injury mechanism. These preliminary results suggest that simulating follower load that may be similar to in vivo muscle forces results in significantly different impact kinetics than in many biomechanical tests where musculature is not simulated.

PMID: 23775333 [PubMed – as supplied by publisher]

Share to care...

Share on facebook
Share on twitter
Share on pinterest
Share on google
Share on linkedin
Share on skype

What we do...

The Harley Street Hospital


What is London spine unit and How it Works

The London Spine Unit was established in 2005 and has successfully treated over 5000 patients. All conditions are treated.

We treat all spinal disorders

The London Spine Unit specialises in Minimally Invasive Treatments allowing rapid recovery and return to normal function

Trusted by patients worldwide

The London Spine Unit provides the highest quality care to all patients and has VIP services for those seeking exceptional services

What our patients say about us ......