ON THE VARIATIONS OF CERVICAL DERMATOMES

Background: Nerve-root related dermatomes have been considered to have quite solid anatomical framings. However, especially in the lumbar region, studies have questioned such firm anatomy. Regarding the cervical nerve roots, many studies have shown an overlap between different dermatomes, which of course affects decisions taken in the clinical work. All the same, dermatome drawings with clear borders are still widely used. Context and purpose of the study: We conducted a literature review in order to find today’s state of the art, including the methods on which the anatomical atlases have been based. The overall pragmatic thoughts were to create summarized guide for clinicians when trying to correlate an MRI-demonstrated prolapse/recess stenosis to pain and neurologic findings, particularly if the nerve root’s peripheral neurology does not follow conventional anatomy. Results: We isolated 24 studies that sufficiently dealt with the issue of cervical dermatomes. Pain and sensory disturbance caused by cervical root affection could deviate from the dermatomal patterns. We found indications that sometimes no paralysis or anaesthesia would be seen after section of a single root. Because the fraction of cases without classical fit between nerve root and anatomical level cannot be given, studies should go into this issue. Conclusion: There are many studies showing that dermatomal distributions are varying, and not only overlapping. We therefore mean that new studies, with modern imaging and surgical techniques, are much needed.