Abstract
Background and purpose
Craniocervical dissociation is a rare and life-threatening injury that results from a significant hyperflexion-hyperextension force. Occult craniocervical dissociation is defined as an unstable craniocervical injury in the absence of atlanto-occipital joint space widening or other skull base line abnormality. The early and accurate diagnosis of craniocervical dissociation is crucial since the early diagnosis and subsequent stabilization with occipital-cervical fusion has been shown to reduce neurologic morbidity and mortality. Several normative skull base lines have been developed to predict craniocervical dissociation. The purpose of our study was to measure the atlanto-occipital joint space and four other common skull base lines in patients who underwent occipital-cervical fusion for post-traumatic craniocervical instability.
Materials and methods
Patients who underwent occipital-cervical fusion for craniocervical injury were identified retrospectively using a keyword search of radiology reports using Nuance mPower software. The cervical CT and MRI exams for these patients were reviewed and the atlanto-occipital joint space, Powers ratio, Wackenheim line, posterior axial line, and basion dens interval were measured. Detailed descriptions of craniocervical ligament injuries on MRI were recorded along with patient demographic information, clinical history, management, and outcome.
Results
Nine adult patients who underwent occipital-cervical fusion for an acute craniocervical injury were identified. Six patients demonstrated an atlanto-occipital joint space measuring 2 mm or less on cervical spine CT with no additional abnormality in the Powers ratio, Wackenheim line, posterior axial line, or basion-dens interval. Three patients demonstrated widening of the atlanto-occipital joint space with two patients demonstrating an abnormality in at least two additional skull base lines. Clinical outcomes were variable with nearly half of the patients demonstrating persistent neurologic deficits, including one quadriplegic patient.
Conclusions
A normal atlanto-occipital joint space and skull base line measurements on cervical CT demonstrated a low predictive value for detecting unstable craniocervical injuries. Occult craniocervical dissociation was present in two-thirds of patients who underwent occipital cervical fusion for acute, craniocervical trauma. A high clinical and radiologic index of suspicion for craniocervical trauma with subsequent follow-up cervical MRI to directly evaluate ligamentous integrity is necessary to accurately diagnose and triage patients with high velocity trauma.
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References
Bellabarba C, Mirza SK, West GA, Mann FA, Dailey AT, Newell DW, Chapman JR (2006) Diagnosis and treatment of craniocervical dislocation in a series of 17 consecutive survivors during an 8-year period. J Neurosurg Spine 4:429–440. https://doi.org/10.3171/spi.2006.4.6.429
Hadley MN, Walters BC, Grabb PA, Oyesiku NM, Przybylski GJ, Resnick DK, Ryken TC, Mielke DH (2002) Guidelines for the management of acute cervical spine and spinal cord injuries. Clin Neurosurg 49:407–498
Tubbs RS, Hallock JD, Radcliff V, Naftel RP, Mortazavi M, Shoja MM, Loukas M, Cohen-Gadol AA (2011) Ligaments of the craniocervical junction. J Neurosurg Spine 14(6):697–709. https://doi.org/10.3171/2011.1.SPINE10612
Offiah CE, Day E (2017) The craniocervical junction: embryology, anatomy, biomechanics and imaging in blunt trauma. Insights Imaging 8:29–47. https://doi.org/10.1007/s13244-016-0530-5
Dundamadappa S, Cauley K (2012) MR imaging of acute cervical spinal ligamentous and soft tissue trauma. Emerg Radiol 19:277–286
Menezes A, Traynelis V (2008) Anatomy and biomechanics of normal craniovertebral junction (a) and biomechanics of stabilization (b). Child’s Nerv Syst 24:1091–1100
Singh AK, Fulton Z, Tiwari R, Zhang X, Lu L, Altmeyer WB et al (2017) Basion-cartilaginous dens interval: an imaging parameter for craniovertebral junction assessment in children. AJNR Am J Neuroradiol 38(12):2380–2384
Smith P, Linscott LL, Vadivelu S, et al 2015 Normal development and measurements of the occipital condyle-C1 interval in children and young adults. AJNR Am J Neuroradiol 2015 Oct 29. [Epub ahead of print] https://doi.org/10.3174/ajnr.A4543 pmid:26514612
Pang D, Nemzek WR, Zovickian J 2007 Atlanto-occipital dislocation, part 2: the clinical use of (occipital) condyle-C1 interval, comparison with other diagnostic methods, and the manifestation, management, and outcome of atlanto-occipital dislocation in children. Neurosurgery 2007;61:995–1015; discussion 1015 https://doi.org/10.1227/01.neu.0000303196.87672.78 pmid:18091277.
Gire JD, Roberto RF, Bobinski M, et al 2013 The utility and accuracy of computed tomography in the diagnosis of occipitocervical dissociation. Spine J 2013;13:510–19 https://doi.org/10.1016/j.spinee.2013.01.023 pmid:23434369.
Kwong Y, Rao N, Latief K 2011 Craniometric measurements in the assessment of craniovertebral settling: are they still relevant in the age of cross-sectional imaging?. AJR Am J Roentgenol. 2011;196 (4): W421-
Nidecker AE, Shen PY (2016) Magnetic resonance imaging of the craniovertebral junction ligaments: normal anatomy and traumatic injury. J Neurol Surg B Skull Base 77(5):388–395. https://doi.org/10.1055/s-0036-1584230
Stassen NA, Williams VA, Gestring ML, Cheng JD, Bankey PE (2006) Magnetic resonance imaging in combination with helical computed tomography provides a safe and efficient method of cervical spine clearance in the obtunded trauma patient. J Trauma 60(1):171–177
Siddiqui J, Grover PJ, Makalanda HL et al (2017) The spectrum of traumatic injuries at the craniocervical junction: a review of imaging findings and management. Emerg Radiol 24:377–385. https://doi.org/10.1007/s10140-017-1490-x
Deliganis AV, Baxter AB, Hanson JA, Fisher DJ, Cohen WA, Wilson AJ et al (2000) Radiologic spectrum of craniocervical distraction injuries. Radiographics 20:S237–S250
Martinez-Del-Campo E, Kalb S, Soriano-Baron H, Turner JD, Neal MT, Uschold T, Theodore N (2016) Computed tomography parameters for atlantooccipital dislocation in adult patients: the occipital condyle-C1 interval. J Neurosurg Spine 24(4):535–545. https://doi.org/10.3171/2015.6.SPINE15226
Kasliwal MK, Fontes RB, Traynelis VC (2016) Occipitocervical dissociation-incidence, evaluation, and treatment. Curr Rev Musculoskelet Med 9(3):247–254. https://doi.org/10.1007/s12178-016-9347-6 (PMID: 27255101)
J H Harris, Jr, G C Carson, L K Wagner, and N Kerr 1994 Radiologic diagnosis of traumatic occipitovertebral dissociation: 2. Comparison of three methods of detecting occipitovertebral relationships on lateral radiographs of supine subjects. American Journal of Roentgenology 1994 162:4, 887–892.
John Christopher Bertozzi, Carlos Andres Rojas, and Carlos Rodrigo Martinez 2009 Evaluation of the pediatric craniocervical junction on MDCT. American Journal of Roentgenology 2009 192:1, 26–31.
Lustrin ES, Karakas SP, Ortiz AO et al (2003) Pediatric cervical spine: normal anatomy, variants, and trauma. Radiographics 23:539–560
Baker C, Kadish H, Schunk JE (1999) Evaluation of pediatric cervical spine injuries. Am J Emerg Med 17:230–234
Rojas CA, Bertozzi JC, Martinez CR, Whitlow J (2007) Reassessment of the craniocervical junction: normal values on CT. AJNR 28:1819–1823
Li G, Passias P, Kozanek M et al (2009) Interobserver reliability and intraobserver reproducibility of powers ratio for assessment of atlanto-occipital junction: comparison of plain radiography and computed tomography. Eur Spine J 18:577–582
Adams, V., "Neck injuries: III. Ligamentous injuries of the craniocervical articulation without occipito-atlantal or atlanto-axial facet dislocation. A pathologic study of 21 traffic fatalities," J Forensic Sci 38 5 0 1097–1104, https://doi.org/10.1520/JFS13513J. ISSN 0022–1198.
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We would like to acknowledge Chris Brown for his illustrations.
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Fiester, P., Rao, D., Soule, E. et al. Occult craniocervical dissociation on cervical CT: an under-appreciated presentation of craniocervical trauma requiring occipital cervical fusion. Emerg Radiol 29, 383–393 (2022). https://doi.org/10.1007/s10140-022-02018-4
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DOI: https://doi.org/10.1007/s10140-022-02018-4