Biometric Analysis of Cervical and Thoracolumbar Movement During Simulated Ambulance Trauma Transport

Introduction—EMS systems have used the long spine board (LSB) to “immobilize” patients with potential spine injury. Recent evidence suggests the LSB may do little to manage spinal motion and may pose greater risk than benefit. This project sought to precisely measure cervical and thoracolumbar (TL) motion during ambulance transport.

Hypothesis—Transport on a mattress with the head elevated without the LSB would allow less spinal movement than transport on a LSB.

Methods—This was a randomized healthy volunteer crossover trial. Real-time 3D motion analysis of spinal motion was measured using biometric sensors (Xsens Technologies, Netherlands). Positions analyzed included: zero and 10 degrees on LSB, and stretcher without LSB with stretcher head elevated to 10, 30, 45 and 60 degrees. Subjects on stretcher without LSB had a c-collar and were transported with and without head blocks. Simulated ambulance transport was on city streets at or below posted speed limits. Descriptive statistics were used to describe movement for each position, and significance was determined using a t-test.

Results—Nine subjects participated, 66% male. For cervical movement, there was no difference in axial, flexion/extension or rotation (.21 ± 0.07 mm vs. 0.22 ± .05 mm, 24 ± 12 mm vs. 22 ± 10 mm, 5.1 ± 19 vs. 5.8 ± 20 degrees, respectively). There were significant differences in lateral (3.7 ± 7 mm LSB vs. 2.0 ± 5 mm no LSB) movement and volumetric movement of the head (120 ± 172 mm³ LSB vs. 77 ± 86 mm³ no LSB). Positions allowing the lowest mean cervical volume of head movement were bed elevated to 30 and 45 degrees with head blocks (20 ± 22 mm³ and 12 ± 6 mm³, respectively). For TL movement, there was no statistical difference in three-dimensional volumetric movement of the TL spine (2 ± 0.6 mm³ LSB vs. 4.7 ± 5 mm³ no LSB).

Conclusion— Spinal motion during transport was small in all groups; however, those secured on a stretcher mattress without LSB had less cervical spine motion than did those secured to LSB. Of the 10 immobilization treatments studied, subjects secured to a stretcher mattress with the head of the bed elevated to 30 degrees had the least spinal movement.