Bertel Rune Kaale

Magnetic Resonance Imaging Assessment of Craniovertebral Ligaments and Membranes After Whiplash Trauma

Study Design. Review article. Objectives. To review the literature on soft tissue lesions of the upper cervical spine in whiplash trauma with focus on imaging. Summary of Background Data. Whiplash injury is associated with chronic impairment in a substantial number of patients. There are different opinions as to the nature and prognosis of this condition, and the role of diagnostic imaging is debated. Methods. Review the literature on the anatomic source of the chronic whiplash syndrome. Review the literature on imaging of the upper cervical spine, emphasizing on the authors own research. Results. MRI shows structural changes in ligaments and membranes after whiplash injury, and such lesions can be assessed with reasonable reliability. Lesions to specific structures can be linked with specific trauma mechanisms. There is a correlation between clinical impairment and morphologic findings. Conclusion. Whiplash trauma can damage soft tissue structures of the upper cervical spine, particularly the alar ligaments. Structural lesions in this area contribute to the understanding of the chronic whiplash syndrome.

MRI assessment of normal ligamentous structures in the craniovertebral junction

We have established an imaging protocol in order to characterise the normal ligamentous structures in the craniovertebral junction. Thirty volunteers without a history of car accident or head or neck trauma underwent MR imaging with 2-mm-thick proton-density-weighted sections in three orthogonal planes. The alar ligaments were clearly seen in every case and had three different configurations in cross-section: round, ovoid or wing-like. A broadening from lateral to medial in the coronal plane was observed in all cases. The transverse ligament was clearly demonstrated in 26 out of 30 cases. The ligament was flattened where it arched across the dens. Towards the insertions the ligament twisted into an oblique-horizontal orientation. The lower tectorial membrane had a median portion merging with the dura, and a lateral portion separated from it. Between the dens and clivus this membrane either merged totally with dura or was partly separated from it by a thin layer of fat. The posterior atlanto-occipital membrane was clearly demonstrated. It either merged with the dura or was partly or totally separated from it by a fat layer. The anterior atlanto-occipital membrane was inconsistently seen and could not be evaluated. Our refined MR protocol improves the visualisation of the craniovertebral ligamentous structures, and may in the future give new insight into post-traumatic neck disorders up to now poorly understood.

MR analysis of the transverse ligament in the late stage of whiplash injury.

Purpose: To analyse and classify structural changes in the transverse ligament in the late stage of whiplash injury by use of high-resolution MRI, and to evaluate the reliability of our classification. Material and Methods: Ninety-two whiplash-injured (2–9 years previously, mean 6 years) and 30 non-injured individuals underwent proton-weighted MR imaging of the craniovertebral junction in three orthogonal planes. Structural changes in the transverse ligaments were graded twice (grades 1–3) based on increased signal, independently by 3 radiologists with a 4-month interval. Inter- and intraobserver statistics were calculated by ordinary and weighted kappa (K). Results: Image quality was excellent in 109 cases and slightly reduced in 13. Twenty-two out of 30 ligaments in the control group were classified as normal (73%) compared with only 32 out of 92 in the injured group (36%). Two or all 3 observers agreed in their grading in 101 out of 122 ligaments (83%). Intraobserver agreement (weighted K) was fair to good (0.33–0.73). Pair-wise interobserver agreement was fair (0.24–0.39). Reasons for divergent grading were insufficient knowledge of normal variations, low signal intensity in the peridental soft tissue obscuring the ligament and interpretation flaw. Conclusion:Whiplash trauma can damage the transverse ligament. By use of high-resolution proton-weighted MR images such lesions can be detected and classified. The reliability of this classification still needs improvement.