Mark J. Spoonamore, M.D.

spine

Cervical Spine Fractures & Dislocations

Overview

A cervical fracture means that a bone is broken in the cervical (neck) region of the spine. A cervical dislocation means that a ligament injury in the neck has occurred, and two (or more) of the adjoining spine bones have become abnormally separated from each other, causing instability. Patients can have a cervical fracture or dislocation, or both. Fractures and dislocations of the cervical spine are not uncommon, and account for almost half of all spinal column injuries that occur every year. According to a study published by Lasfargues in 1995, over 25,000 cervical fractures occur each year in the United States. The majority of fractures and dislocations of the spinal column occur in the cervical spine because it is the most mobile portion of the spinal column, and understandably, the most vulnerable to injury. Although the lumbar (low back) region is most commonly injured during daily laborious, low-energy activities, the neck is most likely to be injured during high-energy trauma such as motor vehicle accidents.

Cervical fractures and dislocations are typically classified according to their region/location and injury/fracture pattern. Because of the unique anatomy of the spine in the region close to the head, cervical injuries are categorized as occipital-cervical (occiput-C2) and subaxial cervical spine (C3-C7) injuries. Within each of these categories, injuries are further stratified according to the specific location of injury and injury/fracture pattern.

Occipital-Cervical Spine (Occiput-C2)

  • Atlanto-Occipital Dislocation (AOD)
  • Occipital Condyle Fracture
  • Atlanto-Axial Instability
  • Atantoaxial Rotatory Subluxation
  • Atlas Fractures (C1)
  • Odontoid Fractures (C2 dens)
  • Traumatic Spondylolisthesis of the Axis (C2)
  • Axis Fractures (C2 vertebral body)

Subaxial Cervical Spine (C3-C7)

  • Distraction-Flexion (Facet fracture/dislocation)
  • Vertical Compression (Burst fracture)
  • Compression-Flexion (Teardrop fracture)
  • Compression-Extension
  • Distraction-Extension
  • Lateral Flexion

Causes

The most common causes of cervical fractures and dislocations are motor vehicle accidents, falls, violence, and sports activities. The abrupt impact and/or twisting of the neck that occurs in a millisecond during the trauma can cause the spine bones to crack or the ligaments to rupture, or both. The initial trauma or event may cause a cervical fracture and/or instability, which may also cause damage to the spinal cord and neurologic structures. The resultant spinal cord injury and neurologic deficit, if it occurs, is the most devastating aspect of a cervical injury, primarily because it is often irreversible and permanent. The majority of spinal column and spinal cord injuries occur in males between the ages of 15 and 24 years old.

Symptoms

Patients with cervical fractures typically have significant, localized neck pain and stiffness. However, patients with other injuries may complain of pain in other areas and not notice the severity of neck pain. Patients who have neurologic compression or irritation may have numbness or weakness in the arms and/or legs. There may or may not be associated radiating pain symptoms. Upper cervical spine fractures and spinal cord injuries can affect the neurologic control of breathing, and patients may complain of difficulty breathing or the inability to take a deep breath.

Physical Findings

The physical findings for patients with cervical fractures are variable. Patients will typically demonstrate profound tenderness and spasm, with significantly decreased neck range-of motion. There is often visible swelling and ecchymosis (bruising) over the fracture site in the back of the neck. If the fracture/dislocation is severe, there will be a visible and palpable “step-off”, meaning the bones are not lined up properly which can be seen and felt by the examiner. If the spinal nerves are severely compressed, there may be significant weakness and numbness in the arms and/or legs. Patients will have complete loss of strength and sensation in the setting of a complete spinal cord injury. Deep tendon reflexes may be diminished or absent. Pulses and vascularity of the arms and legs should be normal.

Imaging Studies

Plain x-rays of the cervical spine are essential to adequately evaluate a cervical fracture and dislocation. It is sometimes difficult to see a non-displaced or minimally displaced fracture or instability, therefore a Computed Tomography (CT) scan is usually ordered. A CT scan is the best test to verify that a fracture is or is not present. If no fracture is identified, but a patient has neck pain and was involved in large trauma or accident, flexion/extension x-rays are often obtained to verify that there if no evidence of ligamentous instability. A Magnetic Resonance Imaging (MRI) test is useful to evaluate the severity of nerve compression or spinal cord injury, but is less accurate at detecting a fracture than a CT scan. A MRI test should generally always be obtained before performing a reduction procedure (closed or operative) in neurologically intact patients with a cervical fracture/dislocation.

Laboratory Tests

There are no laboratory tests used to diagnose a cervical fracture. Occasionally, specific tests are ordered to rule out infection or other metabolic conditions that may be suspected as an underlying cause.

Diagnosis

Cervical spine fractures and dislocations should always be suspected when a patient has been involved in a trauma or accident, especially those patients with neck pain. The diagnosis can be complicated when the symptoms or physical findings are atypical. Some patients with other fractures or injuries will complain about pain in other locations, but not complain of neck pain.

At times, patients may downplay the severity of the motor vehicle accident or trauma. These scenarios may sway the clinician away from ordering cervical x-rays and imaging studies, which are crucial in the diagnosis of cervical injuries. It is important for the clinician to conduct a thorough history and clinical examination (especially inspection and palpation of the spine) prior to formulating a diagnosis so as not to misdiagnose this condition. Any patient involved in a severe accident or trauma, especially those patients with neck pain, should be carefully evaluated with x-rays (and additional imaging studies if necessary) to accurately diagnose a cervical injury.

Treatment Options

The treatment options for patients with a cervical fracture and/or dislocation are limited, and can be categorized as conservative (nonoperative) and surgical (operative). Initial treatment of severe cervical fractures and dislocations may involve skeletal traction and closed reduction, with metal pins placed in the skull connected to a pulley, rope, and weights. Nonoperative treatments include brace (orthotic) treatment and medications. There are a wide range of cervical orthoses, and range from soft collars to hard plastic cervical-thoracic orthoses to halo vest immobilization (using pins anchored into the skull stabilized by a padded plastic vest). Surgical treatments frequently involve posterior (back of the neck incision) cervical fusion (mending the spine bones together) and instrumentation (small metal screws and rods stabilizing the spine). Other options include anterior (front of the neck incision) decompression and fusion, with or without instrumentation (metal plate and screws). Severely unstable fractures may require anterior and posterior neck surgery. The overall goals of treatment are to preserve or improve neurologic function, provide stability, and decrease pain. If these goals can be accomplished with conservative (nonoperative) means, then that is generally preferred. However, because many cervical fractures and dislocations are highly unstable and will not adequately heal on their own, surgical stabilization is routinely performed. Surgical decompression (removal of bone fragments off of the spinal cord) may also be necessary to maximize a patient’s chances for neurologic improvement and recovery from a spinal cord injury.

The general guidelines and treatment recommendations for various types of cervical injuries are listed below.

Atlanto-Occipital Dislocation (AOD)

  • Initially, all should be carefully reduced with positioning, halo vest. Almost all require Occ-C2 PSF.

Occipital Condyle Fractures

  • Type I and II  Cervical orthosis or CT orthosis for 6-8 weeksWith occipital condyle separated from occiput, use halo vest for 8-12 weeks
  • Type III  No AO instability, use Cervical or CT orthosis for 6-8 weeksMinimal displacement, use halo vestIf AO instability (bilateral fractures), need Occ-C2 PSF

Atlanto-Axial (C1-C2) Instability (TAL Insufficiency)

  • Cord at risk if > 5mm instability
  • If > 3 attenuated, >5 ruptured, >7mm  need surgery
  • If C1 fx with >7mm displ of lateral masses, TAL is insufficient. May use halo vest 10-12 weeks while C1 heals, then do C1-C2 PSF.
  • Can try halo in children.

Atlantoaxial Rotary Subluxation

  • Reduction with halo traction. Treat according to according to TAL insufficiency guidelines. C1-C2 PSF if pain with fixed deformity.

Atlas (C1) Fracture

*Mostly nonoperative*

  1. Bilateral posterior arch fx and Burst/lat mass with < 2mm displ  Cervical orthosis 10-12 weeks
  2. Burst or lateral mass fx with 2-7 mm displ  Halo traction 5-10 lbs. 7 days, then Halo vest for 3 months
  3. Burst or lateral mass fx with > 7 mm displ  Halo traction stryker frame 4-6 weeks, then halo vest for 6- 8 weeks
  4. *Occasional C1-C2 fusion for AA instability

Odontoid (C2) Fracture

      • Type I – Orthosis
      • Type II – Less than 5mm displ and 10 degrees angulation  immediate halo vest
      • 5mm displ/10 degrees angulation  reduction with halo traction, then C1-C2 PSF or Anterior odontoid screw fixation, PSF with Magerl technique, or Occ-C2 PSF.
      • Type III – Less than 5mm displ/10 ang  immediate halo vest > 5mm dsipl/10 degree ang  reduction with halo traction, then halo vest

Traumatic Spondylolisthesis of the Axis (C2)

  • Type I – cervical orthosis 3 months (halo vest does not restrict toggle)
  • Type II – Reduction with halo traction 4-6 weeks, then halo vest. Occasionally C2 pedicle lag screws for risk of bedrest, unable to mainatin reduction
  • Type IIA – Immediate halo vest under image intensification, using the vest to help achieve extension and compression, use for 3 months.
  • Type III – Open reduction of C2, then C2-3 PSF with C2 pedicle lag screw. Check MRI prior to Open reduction  ACDF then PCF if HNP is large.

Subaxial Fractures (C3-C7)

  • DF – Closed reduction, then PCF. ACDF then PCF if HNP. Check MRI prior to Open reduction, and prior to closed reduction in intact patients.
  • CF – Stable with min kyphosis, stable posterior ligaments  Cervical orthosis 6-10 weeksUnstable with significant kyphosis, canal compromise  ACVF +/- PCF
  • VC – Stable with min kyphosis, no canal comp  cervical orthosis 6-8 weeksUnstable w/ kyphosis/canal comp  ACVF
  • CE – check for disc injury, may need ACDF if unstable.
  • DE – ACDF if unstable.
  • LF – ACDF vs PCF if unstable.

Although there are guidelines for the treatment of cervical fractures and dislocations, the specific treatment of a cervical fracture and/or dislocation ultimately depends on a number of factors.

  • type and location of fracture
  • severity of fracture and amount of displacement
  • presence of spinal cord/nerve compression
  • presence of neurologic dysfunction or spinal cord injury
  • patient’s age, medical condition, and associated injuries

The clinician should carefully evaluate a patient’s injuries, and with the general management guidelines for cervical fractures in mind, individualize the treatment based on all of the above-mentioned factors.

Selected Bibliography

Aebi M, Zuber K, Marchesi D: Treatment of cervical spine injuries with anterior plating. indications, techniques, and results. Spine 1991;16S:38.

Allen BL, Ferguson RL, Lehmann TR, et al: A mechanistic classification of closed, indirect fractures and dislocations of the lower cervical spine. Spine 1982;7:1.

Anderson LD, D’Alonzo RT. Fractures of the odontoid process of the axis. J Bone Joint Surg 1974; 56A (8):1663.

Anderson PA, Bohlman HH: Anterior decompression and arthrodesis of the cervical spine: long-term improvement. Part II. Improvement in complete traumatic quadriplegia. J Bone Joint Surg Am1992;74:683.

Anderson PA, Montesano PX: Morphology and treatment of occipital condyle fractures. Spine 1988;13:731.

Bohlman HH: Acute fractures and dislocations of the cervical spine. an analysis of three hundred hospitalized patients and review of the literature. J Bone Joint Surg Am 1979;61:1119.

Botte MJ, Byrne TP, Abrams RA, Garfin SR. The halo skeletal fixator: Current concepts of application and maintenance. Orthopedics 1995;18:463.

Bucholz RW, Burkhead WZ: The pathological anatomy of fatal atlantooccipital dislocations. J Bone Joint Surg Am 1979;61:248.

Clark CR, White AA III. Fractures of the dens. A multicenter study. J Bone Joint Surg [Am] 1985; 67: 1340.

Effendi B, Roy D, Cornish B, et al: Fractures of the ring of the axis. a classification based on the analysis of 131 cases. J Bone Joint Surg Br 1981;63:319.

Eismont FJ, Arena MJ, Green BA. Extrusion of an intravertebral disc associated with traumatic subluxation and dislocation of cervical facets. J Bone Joint Surg [Am] 1991; 73: 1555.

Hadley MN, Dickman CA, Browner CM, Sonntag VKH. Acute traumatic atlas fractures: Management and long-term outcome. Neurosurgery 1988;23:31.

Han SY, Witten DM, Mussleman JP. Jefferson fracture of the atlas. J Neurosurg 1976;44:368.

Jeanneret B, Magerl F. Primary posterior fusion C1-C2 odontoid fractures: Indications, technique, and results of transarticular screw fixation. J Spinal Disord 1992;5:464.

Jefferson G. Fractures of the atlas vertebra. Br J Surg 1920;7:407.

Levine AM, Edwards CC: The management of traumatic spondylolisthesis of the axis. J Bone Joint Surg Am 1985;67:217.

Rizzolo SJ, Vacarro AR, Cotler JM: Cervical spine trauma. Spine 1994;19:2288.

Spence KF, Decker S, Sell K. Bursting atlantal fracture associated with rupture of the transverse ligament. J Bone Joint Surg [Am] 1970;52:543-9.

Traynelis VC, Marano GD, et al: Traumatic atlanto-occipital dislocation. J Neurosurg 1986;65:863.

Zimmerman E, Grant J, Vise WM, Yashon D, Hunt WE. Treatment of Jefferson fracture with a halo apparatus. J Neurosurg 1976;44:372.