Tag Archives: clearance

How To: Flexion / Extension Views of the Cervical Spine

Clearance of the cervical spine can often be done using clinical criteria alone (see this video at http://youtu.be/NhjF9kDOcjE). If this is not possible, a combination of radiologic and clinical evaluation is usually carried out. 

In some cases, radiographic studies (usually CT) are normal, but there is pain on clinical exam. Our next step is to send the patient to xray for flexion and extension views. This exam is performed by removing the collar while the patient is sitting, so the thoracic and lumbar spines must be clear before ordering this. The patient then gently flexes and extends the neck to their limits of comfort. Images are then obtained at the limits of flexion and extension. The premise is that a normal, awake patient cannot and will not move their neck beyond their comfort level to the point where they could cause themselves neurologic injury. 

It is very important that you look at the images yourself. The radiologist may review the images and will report that “there is no evidence of subluxation at the limits of flexion and extension.” But the patient may have barely moved their neck!

The question is: how much flexion and extension do you need to have to clear the spine?

The answer is not easy to find, and is buried in literature from the 1980s and 90s. According to the EAST guidelines, the ideal amount is 30 degrees from neutral for both flexion and extension. This is not always achievable in elderly patients, so in those cases you must use your judgment. Talk to the patient to find out if they stopped moving their neck forward or backward due to pain, or because they just can’t move it that far.

Trouble signs to look for are:

  • Subluxation of more that 2mm at any level
  • Angulation of more than 11 degrees

Any abnormality should prompt a spine consult.

If the study is not abnormal but the amount of flexion and/or extension is not adequate, there are two options. First, just leave the collar in place and try again in a week or so and try again. This will allow any soft tissue injuries to get better and may allow a successful repeat study. The alternative is a more costly and less well-tolerated MRI.


  1. EAST Practice Guidelines, Identifying Cervical Spine Injuries Following Trauma – Update (2000).
  2. Defining radiographic criteria for flexion-extension studies of the cervical spine. Robert Knopp et al. Ann Emerg Med. 2001 Jul;38(1):31-5.

Cervical Spine Clearance in Obtunded Patients

Cervical spine clearance in obtunded trauma patients has always been controversial. Most physicians believe that evaluation of bones and ligaments is required, although there is a minority that say that the spine can be cleared purely by radiographs. This would greatly simplify the process and decrease costs.

A prospective study was presented at EAST in January that evaluated the use of CT alone to clear the c-spine in these patients. It was presented by Claridge et al from MetroHealth in Cleveland, and is an expansion of an earlier prospective they performed. Based on the original study, the protocol was revised and the results of this re-study was presented.

The study involved 197 patients who were victims of blunt trauma, obtunded, and were noted to move all extremities. Short term mortality was 13% and long term mortality was 27%, which shows how badly injured this group was. The average ISS was 23 and the initial GCS was 8.

The following radiographic criteria were used to diagnose a significant c-spine injury:

  • Fracture line extending on 2 consecutive CT slices
  • Marked prevertebral soft tissue swelling or hematoma
  • Malalignment not explained by degenerative changes
  • Abnormal facets or posterior malalignment on sagittal reconstruction
  • Occipital condyle injury involving the craniocervical junction

Followup was performed either by re-examination after awakening (62%), followup by phone or chart review (12%), or MRI for persistent c-spine pain (2%). Thirteen percent died before re-evaluation, and 11% were lost to followup.

Using this protocol, the average hospital day of clearance decreased from 7.5 to 3.3, the incidence of decubitus ulcer from the collar decreased from 5% to 0.5%, and the average length of stay decreased from 23 to 14 days. All of these results were statistically significant.

The authors recognized that long term followup was lacking in this study and there was the potential for missed injury. Power calculations show that there are not enough patients enrolled to give a statistically sound result. The issue of spinal cord injury without radiographic abnormality (SCIWORA) is always a possibility.

The bottom line: clearance based on radiographs alone is still not ready for prime time. Some injuries will ultimately be missed, and a fraction of those can cause devastating injury. The real question to be answered is “How many missed injuries is okay?” Until more and better work is done, some combination of radiographic and clinical techniques must be used.

Reference: A normal CT alone may clear the cervical spine in obtunded blunt trauma patients with gross extremity movement – a prospective evaluation of a revised protocol. Claridge et al, MetroHealth Medical Center. Presented at the 23rd Annual Scientific Assembly of the Eastern Association for the Surgery of Trauma, January 2010.

Can a Normal CT Scan Alone Clear the Cervical Spine in Obtunded Trauma Patients?

This is the first in a series of articles on interesting abstracts presented at the 23rd Annual Scientific Assembly of the Eastern Association for the Surgery of Trauma in Phoenix, Arizona.

C-spine clearance in obtunded trauma patients has been problematic for some time. The options have been:

  • CT plus MRI. This is probably only valid for the first 72 hours after injury, and entails some risk in placing a critically ill patient inside the MRI for 30 minutes or more.
  • CT plus flexion/extension images under fluoroscopy. These are generally only performed by a few brave souls.
  • Leave the collar on until a clinical exam can be performed. This frequently leads to significant skin breakdown problems.

The authors have been reviewing their experience with using CT scan alone. In this paper, they used this technique in patients who met the following criteria:

  • Obtunded
  • Blunt trauma
  • CT normal, as read by a neuroradiologist
  • Moving all extremities

They studied 197 patients, and found no injuries in all surviving patients (11% were lost to followup). One deceased patient had a stable ligamentous injury without spine fracture seen at autopsy. Using this technique resulted in a decrease in the average number of days to spine clearance from 7.5 to 3.3 days, a decrease in skin breakdown from 5% to 0.5%. A decreased length of stay from 23.4 to 13.8 days was also seen, but this could not be attributed to the collar.

Very intriguing! However, the fear of SCIWORA is high in all who clear c-spines. The rarity of this catastrophic problem means that no existing study has the statistical power to show that this type of clearance is safe.

Bottom line: We all need to decide “How many missed injuries is okay?” We will never be able to absolutely clear 100.000% of c-spines by xray alone, or even by adding a clinical exam. This study provides support for one technique, but eventually a catastrophic injury will occur. Who will decide what constitutes an acceptable complication and with what frequency they will occur?

Reference: A Normal CT Alone May Clear the Cervical Spine in Obtunded Blunt Trauma Patients with Gross Extremity Movement – A Prospective Evaluation of a Revised Protocol. Leukhardt, Como, Anderson, Wilczewski, Samia, Claridge. MetroHealth Medical Center, Cleveland, OH.