Introduction

Emergency medical services (EMS) personnel continue to be the first-line responders in dealing with the majority out of hospital emergencies including trauma situations. The ATLS guidelines ( advanced trauma life support) which have been developed in the eighties continue to be the gold standards in assessing and setting priorities in the management of life-threatening injuries in a time-efficient and logical manner. Immobilization of the spine has been an essential part of the teaching in addition to pelvic binders and splinting of long bone fractures. Different medical types of equipment have been developed to allow effectiveness and ease of application in addition to allowing flexibility and vital access for the management of airway and other procedures. 

The need for spinal immobilization is determined when assessing the scene and patient. Consider spinal immobilization when the mechanism of injury creates a high index of suspicion for head or spinal injury. Altered mental status and neurologic deficit are also indicators that spinal immobilization should be considered.[1][2][3][4]

The traditional ATLS teaching for adequate spinal immobilization of a patient in a major trauma situation is a well fitted hard collar with blocks and tape to secure the cervical spine in addition to a backboard to protect the rest of the spine. other devices currently in use are scoop stretcher and vacuum splint. The Kendrick extrication device allows the protection of the spine with the casualty in a seated position while being rapidly extricated from a vehicle or other situations with limited access to allow a full backboard. This however still requires the EMS to pay attention to limiting the movement of the cervical spine by using in-line mobilization until fitted [5].

The 10 edition of the ATLS guidelines and the consensus statement of the American College of Emergency Physicians (ACEP), American College of Surgeons Committee on Trauma (ACS-COT), National Association of EMS Physicians (NAEMSP) states that in the situation of penetrating trauma, there is no indication for spinal movement restriction[6] this in keeping with a retrospective study of the American trauma data bank showed a very low number of unstable spinal injuries needing surgery in the context of penetrating trauma. The study further shows that the number needed to treat achieve potential benefit was much higher than the number needed to harm 1032/66. However, in the case of significant blunt trauma the restrictions continue to be indicated in the following situations:

• Low GCS or evidence of alcohol and drug intoxication
• Midline tenderness either in the back of the cervical spine
• Obvious spinal deformity.
• The presence of other distracting injuries 

The advice for effective restriction continues to be a cervical collar with full-length protection of the spine which is to be removed as soon as possible. This is due to the risk of multilevel injury. However, in the pediatric population, the risk of multi-level injury is low and therefore only cervical spine and not full spinal precautions are indicated ( unless signs or symptoms of other spinal injuries is present)

Rigid collar in a pediatric patient

• Neck pain
• Altered limb neurology not explained by limb trauma
• Muscle spasm of the neck (torticollis)
• Low GCS 
• High-risk trauma (e.g., high energy motor vehicle accident, hyperextension neck injury, and significant upper-body injury).

Issues of Concern

There is a growing body of evidence and concern that field triaging has lead to the overuse of spinal immobilization methods and that some patients are potentially coming to harm[7][8][9][10]. 

Potential problems with spinal immobilization:

• Discomfort and distress for the patient[11]
• Lengthening the prehospital time with a potential delay of important investigations and treatment in addition to interfering with other interventions[11].
• Restriction to respiration by the straps in addition to poorer respiratory function in the supine position compared to an upright position. This is especially important in the case of chest trauma either blunt or penetrating[12][13] Difficulty with intubation[14]
• The case of patients with Ankylosing spondylitis or preexisting spinal deformity where actual harm could be caused by forcing the patient to conform to the predetermined position of a rigid cervical collar and backboard[15].

A new Scandinavian literature review which was carried out to review the available evidence for spinal movement restrictions [16] gives very valuable insight into comparing methods of prehospital spine stabilization with the assessment of the strength of the evidence.

Hard Collar

The hard collar has been used since the mid-1960s as a way of stabilization of the cervical spine with low-quality evidence to support its positive influence on the neurological outcome of cervical spine injury with potential negative effects with a significant rise of intracranial pressure and dysphagia [17]. It suggests as well that an alert cooperative patient, with muscle spasm caused by injury, will unlikely have significant displacement as noted in cadaveric studies trying to study the effect of an injury. The article suggests balancing the risks and benefits of this intervention. The American Association of neurological surgeons however continues to suggest the hard collar as a method for stabilizing the cervical spine in pre-hospital scenario[18]

Hardboard

The original spinal longboard has been used in conjunction with the hard collar, blocks, and straps to achieve immobilization of the spine. There is currently evidence of the potential harm especially pressure sores over the sacrum[19][20] This particularly true in the case of spinal injury with no protective sensation. The soft vacuum mattress offers a more gentle surface which protects from the effects of pressure sores while at the same time offers enough support if extended above the level of the head[16]

Blocks

Blocks have been part of the inline mobilization strategy for stabilization of the spine it seems to be effective when strapping the patient on a spinal board of achieving a degree of immobilization with no added benefit of using the hard collar in conjunction [21]

Vacuum Mattress

When comparing the vacuum mattress with hardboard on their own that mattress offers more control and less movement during application and lifting compared to the hardboard [22]. Taking into consideration the risk of pressure sores the mattress seems to offer a better option for patient transport. 

Clearing the Spine

The NEXUS criteria: an alert person not intoxicated without having any distracting injury has a very low probability of injury in the absence of midline tenderness, neurological deficiency. This seems to be a sensitive screening tool with 99% sensitivity and 99.8% negative predictive value[23]. However, other observational studies have suggested that an alert patient with a cervical spine injury will seek to stabilize his spine and that the presence of distracting injuries (not including the chest) does not affect clinical examination findings of the cervical spine and therefore the spine could be cleared clinically without further imaging[24]. Other studies suggest the same findings for the thoracolumbar spine[25][24]

Clinical Significance

While prehospital spinal immobilization has been performed for decades, current data indicate that not every patient needs to be immobilized. Now the National Association of EMS Physicians and the American College of Surgeons Committee on Trauma suggest a limited application of spinal immobilization. These latest guidelines indicate that the number of patients who may benefit from immobilization is very small. The committee went on to state that empirical utilization of the spinal backboards during transport should be used with caution as in some cases their potential risks outweigh the benefits. Further, in patients who have sustained penetrating trauma and have no obvious neurological deficit, the use of spinal immobilization is not recommended. The EMS worker must use clinical acumen before deciding to use the spinal board.[26]

Finally, spinal immobilization has been associated with back pain, neck pain, and making it very difficult to perform some procedures including imaging. Spinal immobilization has also been associated with respiratory difficulties, especially when large straps are applied across the chest.

While many EMS organizations have adopted these new guidelines on spinal immobilization, this is not universal. Some EMS systems fear litigation if they do not immobilize patients. Patients who should have spinal immobilization include the following:

• Blunt trauma
• Spinal tenderness or pain
• Patients with an altered level of consciousness
• Neurological deficits
• Obvious anatomic deformity of the spine
• High energy trauma in a patient intoxicated from drugs, alcohol, or a distracting injury.