Course and branching pattern of the dorsal rami of the cervical spinal nerves: An attempt to introduce structure into a complex topography

BACKGROUND: The anatomy of the dorsal ramus of the cervical spinal nerves (DR C1-C8) is scarce, and the area is described contradictorily. Their growing importance in diagnosing and treating cervical neuropathies and muscle stiffness makes detailed understanding of the nerve topography essential. Therefore, the aim of this study was to provide a comprehensive and detailed anatomical description of the DR C1-C8, focusing on their branching patterns, anastomoses, and topographic relationships. METHODS: In 15 anatomic specimens (30 sides), the cervical spine was dissected via a dorsal approach with special attention on the number of main branches of the DR C1-C8, their course, and innervation patterns. RESULTS: As a main result, a distinct intermediate branch of the cervical DR was observed in over 70% of specimens. In addition, communicating branches were found to be present between all segments. As secondary findings, an inconstant bony canal on the atlas for the DR C1 and ligaments between the inferior articular processes separating the medial and intermediate from the lateral branches of the DR were observed. CONCLUSION: The course of the DR C1-C8 varies due to intersegmental topographical differences, making this region difficult to understand. Exact knowledge of their course and targets is necessary for improved diagnostic and therapeutic strategies.