Anatomy Bones and Muscles · MU Pleven

155. Posterior rami of the spinal nerves.

Covers the posterior rami of the spinal nerves, contrasting their size with the anterior rami and outlining their motor supply to back and neck muscles and sensory supply to skin of the neck, back and buttock. Named branches follow: suboccipital, greater and third occipital, and superior and middle cluneal nerves, with segments and territories. Closes with a brief comparison listing the anterior rami and their plexuses.

Inside: 1 section · 1 labelled picture · 10 flashcards · 2 min

Topic 154 of 236 in the MU Pleven syllabus for Anatomy Bones and Muscles (Medicine, Year 2). The free AceMed note covers it in 1 section, about 293 words (2 min of reading), with 10 flashcards.

In this note

  1. POST. BR. OF SPINAL CORD

POST. BR. OF SPINAL CORD

  • The posterior branches are thinner & shorter than the ant. branches
  • Innervate the muscles of the back & neck and provide sensory innervation for the skin for the neck, back & butt.
  1. 1 Suboccipital nerve (nervus suboccipitalis) – the posterior branch of C1
  • – a purely motor nerve for the suboccipital muscles and the semispinalis capitis
  1. 2 Greater occipital nerve (nervus occipitalis major)
  • – the posterior branch of C2
  • – a purely somatosensory nerve for the skin posterior to the interauricular line (a line joining the auricles in the frontal plane)
  1. 3 Third occipital nerve (nervus occipitalis tertius)
  • – the posterior branch of C3
  • – a purely somatosensory nerve innervating a narrow area of the skin medial to the greater occipital nerve
  1. 4 Superior cluneal nerves (nervi clunium superiores)
  • – the posterior branches of L1 to L3
  • – provides somatosensory innervation of the superior gluteal region
  1. 5 Middle cluneal nerves (nervi clunium medii)
  • – the posterior branches of S1 to S3
  • – provides somatosensory innervation of part of the gluteal region

Anterior branches:

  • – are longer and thicker branches than the posterior branches
  • – provide both motor and sensory innervation of the limbs and the hypaxial part of the trunk
  • – provide motor innervation of the muscles of the anterior abdomen, thorax and neck (except for the suprahyoid muscles)
  • – provide sensory innervation of the skin on the anterior aspect of the abdomen and thorax
  1. 1 Cervical plexus (plexus cervicalis) – C1 to C4
  2. 2 Brachial plexus (plexus brachialis) – C4 to T1
  3. 3 Thoracic nerves (nervi thoracici) – T1 to T12
  4. 4 Lumbar plexus (plexus lumbalis) – T12 to L4
  5. 5 Sacral plexus (plexus sacralis) – L4 and L5 and S1 to S4
  6. 6 Coccygeal plexus (plexus coccygeus) – S5 and Co

Read the full note free

The whole note is free with an AceMed account, with its 10 flashcards. Premium adds flashcard recall, highlights and Ask AI.

Start freeAlready a member? Open the note