Biomechanical comparisson between in-line extrication techniques versus kendrick extrication device (ked) in traffic accidents

Introduction: Worldwide, more than 1.35 million lives are lost annually to road traffic accidents. Care is provided on scene to prevent the occurrence of secondary neurological injuries, forming the cornerstone of emergency medical service (EMS) interventions. Controlled extrication for stable patients is common with attempts to limit the range of spinal column movement using techniques such as self-extrication, in line extrication and/or by utilising short extrication jackets (KED or similar). Recently, bio mechanical studies have challenged the use of indoctrinated EMS techniques. This study intends to add to the body of evidence comparing controlled inline extrication technique, zero angle (AZ) versus the short extrication jacket (KED).Method: This is a randomised comparative cohort study analysing the biomechanics of spinal movement during 2 extrication techniques. The study compares a cohort of 74 healthy volunteers of varying sex, height and weight. Volunteers were removed from the simulated vehicle twice using both AZ and KED techniques. Height and weight demographics matched general population attribution. Extrications were undertaken by 12 teams of 3 EMS professionals with more than 5 years experience.Cervical spine motion was measured using a human motion tracker through wireless kinemetry sensors, six infra-red cameras for 3D motion analysis (Spica) and reflective anatomical markers. Wireless inertia sensors were also used to measure the acceleration (accelerometers) and angular velocity (gyroscopes) of the spine during different phases. Primary analysis end points were: head movement, extraction time and patient comfort. Results: The extrication time was significantly shorter with the AZ technique. Head movement was greater when using the KED.The perceived comfort during extrication showed greater comfort in the AZ technique. Conclusion: Extrication technique will vary based on each victim and must be derived upon injury severity. The habitual use of the KED rescue technique needs review especially for taller and obese patients.