1 / 36

Spinal Cord Organization

Spinal Cord Organization. January 9, 2008. Spinal Cord 31 segments terminates at L1-L2 special components - conus medularis - cauda equina no input from the face. Spinal Cord, Roots & Nerves. Dorsal root. Ventral root. Spinal nerve. Dorsal Root Ganglion.

grant-fernandez
Download Presentation

Spinal Cord Organization

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Spinal Cord Organization January 9, 2008

  2. Spinal Cord 31 segments terminates at L1-L2 special components - conus medularis - cauda equina no input from the face

  3. Spinal Cord, Roots & Nerves Dorsal root Ventral root Spinal nerve

  4. Dorsal Root Ganglion Cell bodies of 1st order sensory neurons Afferent

  5. Spinal Cord Cross Section Dorsal root sensory afferent motor efferent Ventral root

  6. Cross Section of Spinal Cord White matter peripheral Gray matter central Central canal

  7. Volume of Gray & White Matter Gray matter enlarges at cervical and lumbar regions. White matter increases at higher levels of the cord.

  8. Central Gray Matter Motor neurons 2nd order sensory neurons Interneurons Glial cells Motor neuron = lower motor neuron = anterior horn cell = second order motor neuron

  9. Organization of Gray Matter Pain Temperature

  10. Organization of Gray Matter Position sense Vibration Pressure Touch

  11. Organization of Gray Matter Position sense from legs Between T1 and L2 enlarged Dorsal nucleus of Clarke 2nd order sensory neuron going to cerebellum Neck & base of Posterior Horn

  12. Organization of Gray Matter Interomedio-lateral horn Between T1 and L2 enlarged Sympathetic neurons (preganglionic) Intermediolateral Horn

  13. Sympathetic Innervation

  14. Organization of Gray Matter . At S2, S3, and S4 Parasympathetic neurons (preganglionic) Intermediolateral Horn

  15. Parasympathetic Innervation

  16. Organization of Gray Matter Modulates motor activity via gamma motor neurons Adjusts briskness of deep tendon reflexes

  17. Organization of Gray Matter Nuclei of alpha and gamma motor neurons Innervates muscle spindles and muscles

  18. Lower Motor Neurons Alpha motor neurons originate from Rexed lamina IX ventral – dorsal organization ventral  extensor muscles dorsal  flexor muscles medial – lateral organization medial  proximal muscles lateral  distal muscles

  19. Somatotopic Organization

  20. Coordinating Role of Interneurons

  21. Breathing Nuclei of alpha and gamma motor neurons LMNs from spinal levels C3, C4 & C5 innervate the phrenic nerve Controls diaphragm

  22. Control Functions Nuclei of alpha and gamma motor neurons At levels S1 - S4 LMNs form Onuf’s nucleus Innervates anal and urethral spincters; needed for sexual function

  23. Sacral cord

  24. Configuration of Gray Matter Abundant white matter high in the spinal cord Enlargement of gray matter at the cervical level Innervates arm muscles

  25. Configuration of Gray Matter Enlargement in thoracic region for sympathetic neurons Enlargement in lumbar region for motor neurons to the legs Minimal white matter at the lower cord

  26. Descending Motor Pathway Upper motor neuron 1st order neuron synapses on LMN Crossed pathway Lateral corticospinal Uncrossed pathway Anterior corticospinal

  27. Somatotopic Organization

  28. Spinal Cord Tracts Unconscious position sense movement feedback

  29. ↑ Sensory Gracile tract Leg position & vibration Cuneate tract Arm position & vibration Dorsal spinocerebellar tract Strength & muscle speed Ventral spinocerebellar tract Modulation; interneurons Lateral spinothalamic tract Pain & temperature Anterior spinothalamic tract Light touch Spinocervical thalamic tract Kinesthetic movement & discriminative touch ↓Motor Corticospinal tract Speed & agility Reticulospinal tract Differential facilitation of motor neurons Rubrospinal tract Fix movement errors Lateral vestibulospinal tract Extensor & posture Medial vestibulospinal tract Flexor & head position Tectospinal tract Head turning Ascending & Descending Tracts

  30. Ascending Tracts Sensory Position Vibration Sensory Pain Temperature

  31. Spinal Cord Injury Position Pain Brown – Sequard Syndrome

  32. Transverse vs Hemi Cord Syndrome

  33. Anterior vs Posterior Cord Syndromes

  34. Blood Supply to Spinal Cord

  35. Traumatic Spinal Cord Injury DUI: $100 addt’l fine South Carolina Spinal Cord Injury Research Board

  36. Monday Brainstem

More Related