Tag Archives: clearance

General

Distracting Injury and Cervical Spine Clearance

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One of the tenets of clinical c-spine clearance is that there be no “distracting injury.” What does this mean exactly? Can the clinician adequately judge which injuries are too distracting?

The Loyola group prospectively looked at 160 patients needing c-spine clearance over a 9 month period. GCS had to be 14 or 15, and the patients were excluded if they were intoxicated or received an analgesic prior to the clearance attempt. A total of 84% had no neck pain, and 82% of those had no peripheral, potentially distracting pain. Patients with perceived distracting pain and those without had very similar Visual Analog Scores (VAS) for pain. 

Overall, the majority of patients and physicians did not believe that distracting pain was present, and when pain was present there was little agreement whether it was distracting. The few patients who did have spine fractures had a VAS for pain >5. The use of physician judgment for distracting pain and clearance worked just fine in this study.

Bottom line: The authors recommend using clinician judgment as to the degree of distracting pain when clearing the c-spine. If you want to be more objective, if the patient complains of a Visual Analog Score for pain of more than 5, then you may want to delay clearance. Note: this is a small study that really needs to be replicated before widespread use.

Reference: C-spine clearance: don’t be distracted – just trust your judgment. Presented at the 24th annual scientific assembly of EAST, Session II, Paper 9. Click here to see the abstract. 

General

Cervical Spine Clearance and Altered Mental Status

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Clearance of the cervical spine is a complicated topic, with many opinions and anecdotes. EAST developed a set of practice guidelines in 1998 and updated them in 2000 and again in 2008. They are well-accepted and very helpful.

Spine clearance in an obtunded or intoxicated patient is made even more challenging. Here’s an approach based on the EAST guidelines that I find helpful:

  1. Clear the bones. Obtain a CT of the cervical spine from skull base to T2. Sagittal and coronal 2D reconstructions must be created for review. Conventional images (AP, lateral, odontoid) are of no additional value.
  2. If a fracture is identified, consult your spine service.
  3. If a neurologic deficit is present, obtain an MRI and consult your neurosurgery or spine service.
  4. Clear the ligaments. In the obtunded patient, there are 3 choices: 1) keep the collar on until the patient wakes up enough to be examined, 2) obtain an MRI to evaluate the ligaments, or 3) remove the collar on the basis of CT alone.

In patients that you don’t expect to wake up any time soon, I prefer MRI. Some say that it should be obtained within 72 hours of injury for best accuracy in detecting ligamentous injury. Unfortunately, I have not been able to find any specific literature support for this. If the MRI is negative, the collar can be removed immediately.

There is a growing body of research that suggests that CT alone is sufficient for clearance. My opinion is that this is probably true, but only if the scan is read by a radiologist who is especially skilled in reading CT scans of the cervical spine. A pool radiologist may miss subtle findings that might indicate a ligamentous injury.

Reference: Eastern Association for the Surgery of Trauma practice guideline: Identifying Cervical Spine Injuries Following Trauma – 2009 Update. Click here to download.

General

How To: Flexion / Extension Views of the Cervical Spine

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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.

References:

  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.
General

Cervical Spine Clearance in Obtunded Patients

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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.