Analysis of spine motion during prehospital extrication procedures in motorsport.

PURPOSE: The appropriate extrication techniques for trauma patients after car accidents remain a topic of controversy. Various techniques for immobilizing the cervical spine during prehospital extrication have been investigated. METHODS: This explorative study compared the amount of spinal motion during five different extrication procedures from a racecar and a rallycar performed by two teams: a professional motorsport extrication team and a team of professional emergency medical technicians (EMTs). Two different microelectromechanical systems were used to measure spinal motion, and a motionscore was calculated to compare the amount of remaining spinal motion. A high motionscore indicates high remaining motion and a low motionscore indicates low remaining motion. RESULTS: The use of an extricable seat results in a mean overall motion score of 1617 [95% CI 308-2926]. Emergency extrication without equipment resulted in the lowest overall motionscore 1448 [95% CI 1070-1826]. In case of urgent extrication the Extrication team attained a motionscore of 2118 [95% CI 517-3718] and the EMT team a motionscore of 2932 [95% CI 1427-4435]. When performing the procedure with the aid of a rescue boa, the EMT team achieved an overall mean motionscore in the same range 2725 [95% CI 568-4881] with boa vs. 2932 [95% CI 1427-4435] without boa. When mean scores of individual spinal segments were analyzed, we found that the EMT team did especially worse in immobilizing the cervical spine 198 vs. 758. CONCLUSIONS: Regular training of extrication procedures has paid off considerably in reducing spinal movement during extrication from a racecar. If an extricable seat is available, extrication should be performed using it. However, if emergency extrication is necessary, an additional manual cervical spine immobilization should be conducted using the Rautek maneuver to sufficiently reduce cervical spine movement.

Analysis of cervical spine immobilization during patient transport in emergency medical services.

PURPOSE: It remains controversial how to immobilize the cervical spine (CS) in trauma patients. Therefore, we analyzed different CS immobilization techniques during prehospital patient transport. METHODS: In this explorative, biomechanical analysis of immobilization techniques conducted in a standardized setting, we recorded CS motion during patient transport using a wireless human motion tracker on a volunteer. To interpret spinal movement a benchmark called motionscore (MS) was developed based on biomechanics of the injured spine. RESULTS: We found the best spinal motion restriction using a spine board, head blocks and immobilization straps with and without a cervical collar (CC) (MS 45 vs. 27). Spinal motion restriction on a vacuum mattress with CC and head blocks was superior to no CC or head blocks (MS 103 vs. 152). An inclined vacuum mattress was more effective with head blocks than without (MS 124 vs. 187). Minimal immobilization with an ambulance cot, CC, pillow and tape was slightly superior to a vacuum mattress with CC and head blocks (MS 92 vs. 103). Minimal immobilization without CC showed the lowest spinal motion restriction (MS 517). CONCLUSIONS: We suggest an immobilization procedure customized to the individual situation. A spine board should be used whenever spinal motion restriction is indicated and the utilization is possible. In some cases, CS immobilization by a vacuum mattress with CC and head blocks could be more beneficial. In an unstable status of the patient, minimal immobilization may be performed using an ambulance cot, pillow, CC and tape to minimize time on scene caused by immobilization.

An explorative, biomechanical analysis of spine motion during out-of-hospital extrication procedures.

OBJECTIVES: The extrication of patients following a road traffic collision is among the basic procedures in emergency medicine. Thus, extrication is a frequently performed procedure by most of the emergency medical services worldwide. The appropriate extrication procedure depends on the patient's current condition and accompanying injuries. A rapid extrication should be performed within a few minutes, and the cervical spine (at least) should be immobilized. To our knowledge, the scientific literature and current guidelines do not offer detailed recommendations on the extrication of injured patients. Thus, the aim of the current study is to compare the effectiveness of spinal stabilization during various out-of-hospital extrication procedures. METHODS: This is an explorative, biomechanical analysis of spine motion during different extrication procedures on an example patient. Movement of the cervical spine was measured using a wireless human motion tracker. Movement of the thoracic and lumbar spine was quantified with 12 strain gauge sensors, which were positioned paravertebrally on both sites along the thoracic and lumbar spine. To interpret angular movement, a motionscore was developed based on newly defined axioms on the biomechanics of the injured spine. RESULTS: Self-extrication showed the least spinal movement (overall motionscore sum = 667). Movement in the cervical spine could further be reduced by applying a cervical collar. The extrication by a rescue boa showed comparable results in overall spinal movement compared to the traditional extrication via spineboard (overall motionscore sum = 1862vs. 1743). Especially in the cervical spine, the spinal movement was reduced (motionscore sum = 339 vs. 595). However, the thoracic spine movement was increased (motionscore sum = 812 vs. 432). CONCLUSION: In case of a suspected cervical spine injury, guided self-extrication seems to be the best option. If the patient is not able to perform self-extrication, using a rescue boa might reduce cervical spinal movement compared to the traditional extrication procedure. Since promising results are shown in the case of extrication using a patient transfer sheet that has already been placed below the driver, future developments should focus on novel vehicle seats that already include an extrication device.