Central and Peripheral Nervous System

Description

Posterior anatomy places the encephalon superiorly within the cranial vault, continuous with the spinal cord as it descends through the vertebral canal to the conus medullaris, with the cauda equina fanning inferiorly. Paired dorsal and ventral roots unite to form segmental spinal nerves that exit laterally via the intervertebral foramina, then divide into dorsal rami supplying the intrinsic back muscles and skin and ventral rami coursing anterolaterally toward the limbs and trunk. From the midline cord, peripheral nerves radiate bilaterally in yellow, branching distally into progressively smaller neural twigs across the posterior shoulder girdle, back, gluteal region, and lower limb. A faint musculoskeletal silhouette provides landmarks for depth and segmental level. Posterior presentation matters because it clarifies the relationship between spinal cord segments and the nerve roots at the point where many clinical problems occur. Radiculopathy from posterolateral intervertebral disc herniation or foraminal stenosis affects the exiting ventral ramus distribution, while herpes zoster follows a dorsal root ganglion with a dermatomal rash that wraps from posterior midline toward the lateral trunk. The long continuous cord-to-root layout also supports teaching of lumbar puncture anatomy, where the needle is placed below L2 to avoid the spinal cord and enter the lumbar cistern among cauda equina roots. Level matters. Use this plate for neuroanatomy and gross anatomy instruction when introducing segmental organization, dorsal versus ventral rami, and the transition from central nervous system to peripheral nerves. It also fits well in neurology or spine surgery materials illustrating patterns of sensory loss, referred pain, and root-level localization in back and leg symptoms. Anatomical accuracy verified by SciePro's Medical Advisory Board.