CHIR113 Lecture Notes - Lecture 8: Articular Processes, Dense Irregular Connective Tissue, Intervertebral Disc
3 Aug 2018
School
Department
Course
Professor
2nd of May 2018: Chiropractic Lecture 5 – Lumbar and Thoracic Biomechanical
Anatomy
▪ Lumbar Biomechanical
Anatomy:
o Structure:
− Flexible column
− 24 vertebrae (mobile over 3 moving
regions)
− 7 cervical
− 12 thoracic
− 5 lumbar
− 5 fused segments form the
sacrum
− 4 fused segments form the
coccyx
o Function:
− Support mass of the body and head
− Allow for mobility and flexibility to
absorb energy and protect against
impact
− Protects the spinal cord, nerves and
the vertebral artery in the cervical
region
− Trunk muscles and ligaments act on
individual vertebra for postural control and stability
− Provide shock absorption
▪ Spinal Motion Unit:
− Studied in motion segments
− A spinal motion is 2 adjacent vertebral
bodies and the intervertebral disc
(intervening soft tissue)
o Function- Motion:
− Translation can occur along an axis
(linear motion)
− Rotation can occur around an axis
o Degree of freedom:
− A vertebra moving relative to its adjacent
couple enjoys 6 degrees of freedom – 3
transitional and 3 rotational
▪ Planes of the body:
− Sagittal Plane:
− Divides the body into left and right halves
− Frontal Plane:
− Divides the body into front and back
− Transverse Plane:
− Divides the body into top and bottom sectors
▪ Lumbar Spine Diagram:
▪ Lumbar Vertebra = Typical
Features:
− Large kidney shaped vertebral body
− Long, slender transverse processes
(TVP) that project laterally and
slightly posteriorly
− Short, broad and flat Spinous process
(SP)
− Superior and inferior articular
processes
− (SP) and (TVP) is for muscle
attachment and leverage
▪ Lumbar Vertebral Canal:
− Form of protection
− In other areas of the spine the
vertebral canal (labeled vertebral
foramen here) protects the spinal
cord
− Depending on the location of the
lumbar spine as the spinal cord
ends at L2
− In the lumbar spine the vertebral
canal protects the spinal nerves
− Vertebral body anteriorly
− Posterior arch posteriorly
− Arch = pedicles and laminar
▪ Lumbar Posterior Articulations:
o Facet Joints:
− 2 superior articular processes = facets face
medially and slightly posteriorly
− 2 inferior articular processes = facets face
laterally and slightly anteriorly
− Role of facet: guide and direction motion
− Shape and orientations – facilitates flexion and
extension and limits rotation
− 3 joints = intervertebral disc and 2 facet joints
▪ Lumbar Intervertebral Disc:
− Lies between each adjacent vertebrae
− Made up of fibrocartilaginous joint (a
symphysis) to allow for slight
movement.
− It also acts like a ligament to hold the
vertebrae together
− Role = shock absorbers
− Nutrition via diffusion due to avascular
nature aided by spinal motion
Document Summary
2nd of may 2018: chiropractic lecture 5 lumbar and thoracic biomechanical. 4 fused segments form the coccyx: function: Support mass of the body and head. Allow for mobility and flexibility to absorb energy and protect against impact. Protects the spinal cord, nerves and the vertebral artery in the cervical region. Trunk muscles and ligaments act on individual vertebra for postural control and stability. Provide shock absorption: spinal motion unit: A spinal motion is 2 adjacent vertebral bodies and the intervertebral disc (intervening soft tissue: function- motion: Translation can occur along an axis (linear motion) Rotation can occur around an axis: degree of freedom: A vertebra moving relative to its adjacent couple enjoys 6 degrees of freedom 3 transitional and 3 rotational: planes of the body: Divides the body into left and right halves. Divides the body into front and back. Divides the body into top and bottom sectors: lumbar spine diagram, lumbar vertebra = typical.
