Posterior Branches - Peripheral Nerves

 Posterior Branches

Each posterior branch divides into a medial and a lateral branch. Both supply motor fibers to the deep autochthonous back muscles. Sensory innervation of the back comes mainly from the lateral branches of the posterior branches (AD3). The area sup-plied by the posterior branches of cervical spinal nerves expands widely and includes the occiput (greater occipital nerve) (D4). In the lumbar region, sensory innervation of the back comes from the posterior branches of the lumbar spinal nerves L1 – L3 and the sacral spinal nerves S1 – S3 (superior clunealnerves [D5] and medial cluneal nerves [D6]).


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