Cervical spine immobilisation and imaging

 

The issues

The practice of routinely placing a cervical spine collar on all trauma patients is being questioned. There are no randomised controlled trials demonstrating that cervical immobilisation prevents secondary spinal cord injury. In fact, there is a growing body of evidence that cervical spine collars may cause more harm in some patients.

 

The concerns regarding rigid cervical spine immobilisation are as follows¹

• collars can restrict cranial venous outflow thus increasing ICP and worsening head injury outcomes
• collar placement and strict adherence to manual inline stabilisation can make advanced airway management more difficult and increase aspiration risk
• collars can worsen neurological deficits in some patients
• collars provide limited motion control
• collars can lead to pressure injuries even after a short period
• collars are uncomfortable and can increase cervical spine pain

 

St. Johns have recently adopted an algorithm to decide whether to place a cervical spine collar in the prehospital setting.

Patients may arrive to the ED with a lanyard around their neck stating that the cervical spine is not cleared.

 

ST JOHNS AMBULANCE CERVICAL SPINE IMMOBILISATION ALGORITHM

sja c spine

From: SJA Clinical Procedures and Guidelines Comprehensive Edition (2016-2018)

 

 

Immobilisation of the patient in the ED

 

Where to proceed with these patients once they have arrived in the ED is unclear at this stage.

Some trauma patients can have their C spine cleared by using clinical decision rules²

• Canadian Cervical Spine rule
• NEXUS

 

Others will need to have imaging of their cervical spines and it will be up to the treating clinician and the institution to decide if these patients are going to require immobilisation to facilitate this.

If available in the ED, early application of a less rigid collar (eg: Aspen or Philadelphia) might be another immobilisation option for patients requiring further imaging.

It is suggested that departmental guidelines regarding this are discussed and formalised in conjunction with the radiology department.

 

Role of MRI with suspected cervical spine injury

Three of the traditional indications for MRI in the patient with suspected C-spine injury include: persistent neck tenderness, neurological findings, and  evaluation of the obtunded / unexaminable patient.  Though MRI remains firmly indicated for any patient with an abnormal motor exam, with improving CT technology the role of MRI in those patients with neck tenderness or obtundation after a normal 64 slice CT C-spine has become more debatable.  Previous studies have shown that MRI can detect abnormalities in 7-15% of patients with normal CT C-spines, though almost all of these are not clinically important.

A large multi-centre trial of 10,000 patients in 2016 found that although the sensitivity for CT in detecting clinically significant C-spine injuries was 98.5%, none were missed when CT was combined with a motor exam.  Their conclusion was that MRI adds no clinically useful information in the patient with persistent neck tenderness after a normal 64-slice C-spine CT.  Additionally, there is emerging evidence suggesting that the role of MRI is questionable for patients with isolated paresthesias.   And practice guidelines from major trauma organisations now recommend removing the cervical collar in unconscious or obtunded patients after a negative high quality CT C-spine.

 

 

 

References:

1. Sundstrøm T, Asbjørnsen H, Habiba S, Sunde GA, Wester K. Prehospital use of cervical collars in trauma patients: a critical review. J Neurotrauma. 2014;31(6):531-540.
2. Stiell, Ian G., et al. “The Canadian C-spine rule versus the NEXUS low-risk criteria in patients with trauma.” New England Journal of Medicine26 (2003): 2510-2518
3. Malholtra A, Wu X, Kalra V, et al. Utility of MRI for cervical spine clearance after blunt traumatic injury: a meta analysis. Emergency Radiology. 2017; 27.
4. Resnick S, Inaba K, Karamanos E, et al. Clinical relevance of magnetic resonance imaging in cervical spine clearance. JAMA Surgery. 2014; 149
5. Inaba K, Byerly S, Bush L, et al. Cervical spinal clearance: a prospective Western Trauma Association Multi-Institutional Trial. The Journal of Trauma and Acute Care Surgery. 2016; 81
6. Patel et al. Cervical spine collar clearance in the obtunded adult blunt trauma patient, Journal of Trauma and Acute Care Surgery: February 2015 – Volume 78 – Issue 2 – p 430-441