Tag Archives: Cervical spine

Comparison of Cervical Spine Stabilization

A reader recently asked what the optimal method for inline stabilization is. We’ve been pondering this question for nearly 30 years. In 1983, trauma surgeons at UCLA looked at a number of devices available at that time and tested them on normal volunteers. They measured neck motion to see which was “best.”

Here’s what they found:

  • Soft collar – In general, this decreased rotation by 8 degrees but insignificantly protected against flexion and extension. Basically, this keeps your neck warm and little else.
  • Hard collars – A variety of collars available in that era were tested. They all allowed about 8% flexion, 18% lateral movement, and 2% rotation. The Philadelphia collar allowed the least extension.
  • Sandbags and tape – Surprisingly, this was the best. It allowed no flexion and only a few percent movement in any other direction.

The Mayo clinic compared four specific hard collars in 2007 (Miami J, Miami J with Occian back, Aspen, Philadelphia). They found that the Miami J and Philadelphia collars reduced neck movement the best. The Miami J with or without the Occian back provided the best relief from pressure. The Aspen allowed more movement in all axes.

And finally, the halo vest is the gold standard. These tend to be used rarely and in very special circumstances.

Bottom line:

  • For EMS: Rigid collar per your protocol is the standard. In a pinch you can use good old tape and sandbags with excellent results.
  • For physicians: The Miami J provides the most limitation of movement. If the collar will be needed for more than a short time, consider the well-padded Occian back Miami J (see below).

References:

  • Efficacy of cervical spine immobilization methods. J Trauma 23(6):461-465, 1983.
  • Range-of-motion restriction and craniofacial tissue-interface pressure from four cervical collars. J Trauma 63(5):1120, 1126, 2007.

Dysphagia and Cervical Spine Injury

Cervical spine injury presents a host of problems, but one of the least appreciated ones is dysphagia. Many clinicians don’t even think of it, but it is a relatively common problem, especially in the elderly. Swallowing difficulties may arise for several reasons:

  • Prevertebral soft tissue swelling may occur with high cervical spine injuries, leading to changes in the architecture of the posterior pharynx
  • Rigid cervical collars, such as the Miami J and Aspen, and halo vests all force the neck into a neutral position. Elderly patients may have a natural kyphosis, and this change in positioning may interfere with swallowing. Try extending your neck by about 30 degrees and see how much more difficult it is to swallow.
  • Patients with cervical fractures more commonly need a tracheostomy for ventilatory support and/or have a head injury, and these are well known culprits in dysphagia

Normal soft tissue (<6mm at C2, <22mm at C6)

A study in the Jan 2011 Journal of Trauma outlined the dysphagia problem seen with placement of a halo vest. They studied a series of 79 of their patients who were treated with a halo. A full 66% had problems with their swallowing evaluation. This problem was associated with a significantly longer ICU stay and a somewhat longer overall hospital stay.

Bottom line: Suspect dysphagia in all patients with cervical fractures, especially the elderly. We don’t use halo vests very often any more, but cervical collars can exacerbate the problem by keeping the neck in an unaccustomed position. Carry out a formal swallowing evaluation, and adjust the collar (or halo) if appropriate.

Reference: Swallowing dysfunction in trauma patients with cervical spine fractures treated with halo-vest fixation. J Trauma 70(1):46-50, 2011.

Is Applying Or Removing That Cervical Collar Dangerous?

Cervical collars are applied to blunt trauma patients all the time. And most of the time, the neck is fine. It’s just those few patients that have fracture or ligamentous injury that really need it.

I’ve previously written about how good some of the various types of immobilization are at limiting movement (click here). But what happens when you are actually putting them on or taking them off? Could there be dangerous amounts of movement then?

Several orthopaedics departments studied this issue using an electromagnetic motion detector on “fresh, lightly embalmed cadavers” (!) to determine how much movement occurred when applying and removing 1- and 2-piece collars. Specifically, they used an Aspen 2-piece collar, and an Ambu 1-piece. They were able to measure flexion/extension, rotation and lateral bending.

Here are the factoids:

  • There were no significant differences in rotation (2 degrees) and lateral bending (3 degrees) when applying either collar type or removing them (both about 1 degree)
  • There was a significant difference (of 0.8 degrees) in flexion/extension between the two types (2-piece flexed more). Really? 0.8 degrees?
  • Movement was similarly small and not significantly different in either collar when removing them

Bottom line: Movement in any plane is less than 3-4 degrees with either a 1-piece or 2-piece collar. This is probably not clinically significant at all. Just look at my related post below, which showed that once your patient is in the rigid collar, they can still flex (8 degrees), rotate (2 degrees) and move laterally (18 degrees) quite a bit! So be careful when using any collar, but don’t worry about doing damage if you use it correctly.

Related post:

Reference: Motion generated in the unstable cervical spine during the application and removal of cervical immobilization collars. J Trauma 72(6):1609-1613, 2012.