Difference between revisions of "Spinal Column - Anatomy & Physiology"

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<big><center>[[Musculoskeletal System - Anatomy & Physiology|'''BACK TO MUSCULOSKELETAL ANATOMY AND PHYSIOLOGY''']]</center></big>
 
<big><center>[[Musculoskeletal System - Anatomy & Physiology|'''BACK TO MUSCULOSKELETAL ANATOMY AND PHYSIOLOGY''']]</center></big>
==Divisions and Landmarks==
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=Divisions and Landmarks=
 
The common pattern of canine landmarks, according to Dyce, Sack, et al, can be quantified as such:
 
The common pattern of canine landmarks, according to Dyce, Sack, et al, can be quantified as such:
 
[[Image:Spinal landmarks.jpg|center|500px|Spinal Landmarks - Copyright Becky Pocock 2008]]
 
[[Image:Spinal landmarks.jpg|center|500px|Spinal Landmarks - Copyright Becky Pocock 2008]]
  
==Vertebrae and Joints==
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=Vertebrae and Joints=
 
*Vertebrae consist of a body which encloses the vertebral foramen (through which the spinal cord runs), a spinous process, and a transverse process, as well as articular processes by which they join together
 
*Vertebrae consist of a body which encloses the vertebral foramen (through which the spinal cord runs), a spinous process, and a transverse process, as well as articular processes by which they join together
 
*The form of the spinous process varies with respect to species and region
 
*The form of the spinous process varies with respect to species and region
  
=Cervical Vertebrae=
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==Cervical Vertebrae==
 
*The first two cervical vertebrae are known as the '''atlas''' and the '''axis''' respectively, and are modified to allow movement of the head
 
*The first two cervical vertebrae are known as the '''atlas''' and the '''axis''' respectively, and are modified to allow movement of the head
 
**The atlas has no conventional body: instead it is complsed of two lateral masses joined by dorsal and ventral arches
 
**The atlas has no conventional body: instead it is complsed of two lateral masses joined by dorsal and ventral arches
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*The last (C7) cervical vertebra has a taller spinous process than those proceeding it, and articulates with the first pair of ribs
 
*The last (C7) cervical vertebra has a taller spinous process than those proceeding it, and articulates with the first pair of ribs
  
=Thoracic Vertebrae=
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==Thoracic Vertebrae==
 
*Thoracic vertebrae articulate with the ribs
 
*Thoracic vertebrae articulate with the ribs
 
*They are distingushed by short bodies with flattened extremities, costal facets, short transverse processes, and prominent spinous processes
 
*They are distingushed by short bodies with flattened extremities, costal facets, short transverse processes, and prominent spinous processes
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*The orientation of spinous processes shifts from caudo- to craniodorsal
 
*The orientation of spinous processes shifts from caudo- to craniodorsal
  
=Lumbar Vertebrae=
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==Lumbar Vertebrae==
 
*Longer and more uniform in shape than thoracic vertebrae
 
*Longer and more uniform in shape than thoracic vertebrae
 
*Shorter in height, with long, flattened transverse processes that project laterally
 
*Shorter in height, with long, flattened transverse processes that project laterally
  
=Sacral Vertebrae=
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==Sacral Vertebrae==
 
*'''Sacrum''': a single bone formed by the fusion of several vertebrae that articulates with the pelvic girdle
 
*'''Sacrum''': a single bone formed by the fusion of several vertebrae that articulates with the pelvic girdle
 
*Allows the thrust of the hindlimbs to be transmitted to the trunk
 
*Allows the thrust of the hindlimbs to be transmitted to the trunk
 
*Narrows caudally and is curved to present a concave surface to the pelvic cavity
 
*Narrows caudally and is curved to present a concave surface to the pelvic cavity
  
=Caudal Vertebrae=
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==Caudal Vertebrae==
 
*Number varies greatly even within species
 
*Number varies greatly even within species
 
*Progressive simplification of form
 
*Progressive simplification of form
  
==Spinal Cord==
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=Spinal Cord=
==Hypaxial and Epaxial Muscles==
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=Hypaxial and Epaxial Muscles=

Revision as of 14:20, 24 July 2008

BACK TO MUSCULOSKELETAL ANATOMY AND PHYSIOLOGY

Divisions and Landmarks

The common pattern of canine landmarks, according to Dyce, Sack, et al, can be quantified as such:

Spinal Landmarks - Copyright Becky Pocock 2008

Vertebrae and Joints

  • Vertebrae consist of a body which encloses the vertebral foramen (through which the spinal cord runs), a spinous process, and a transverse process, as well as articular processes by which they join together
  • The form of the spinous process varies with respect to species and region

Cervical Vertebrae

  • The first two cervical vertebrae are known as the atlas and the axis respectively, and are modified to allow movement of the head
    • The atlas has no conventional body: instead it is complsed of two lateral masses joined by dorsal and ventral arches
    • The atlas and axis are fused in embryonic life
    • The wing of the atlas is the transverse process of this vertebra and allows the spinal column to articulate with the skull by providing a resting place for the occipital condyles
    • The axis is the longest vertebra
    • The nuchal ligament connects the spinous process of the axis to the spinous process of the first thoracic vertebra (T1)
  • The last (C7) cervical vertebra has a taller spinous process than those proceeding it, and articulates with the first pair of ribs

Thoracic Vertebrae

  • Thoracic vertebrae articulate with the ribs
  • They are distingushed by short bodies with flattened extremities, costal facets, short transverse processes, and prominent spinous processes
  • They reach a maximum height a few vertebrae behind the cervicothoracic junction (constituting the withers of the horse) and then decline
  • The orientation of spinous processes shifts from caudo- to craniodorsal

Lumbar Vertebrae

  • Longer and more uniform in shape than thoracic vertebrae
  • Shorter in height, with long, flattened transverse processes that project laterally

Sacral Vertebrae

  • Sacrum: a single bone formed by the fusion of several vertebrae that articulates with the pelvic girdle
  • Allows the thrust of the hindlimbs to be transmitted to the trunk
  • Narrows caudally and is curved to present a concave surface to the pelvic cavity

Caudal Vertebrae

  • Number varies greatly even within species
  • Progressive simplification of form

Spinal Cord

Hypaxial and Epaxial Muscles