Module 10: Biomechanics and Motor Control of the Trunk Flashcards
Functions of the spine:
load absorption, movement, stability
5 bony parts of the spine:
Spinous process, lamina, transverse process, body and pedicles
What is the difference between the thoracic spine and other spine sections in terms of the articular surfaces of the joints?
thoracic vertebrae have dens to allow for articulation with the ribs
What are foramen transversarii?
where the blood vessels pass through
What is the intervertebral foramen?
where the nerve roots pass through
What are the structures that provide load absorption in the spine?
intervertebral discs and ligaments
What is the function of the horizontal and vertical trabeculae?
increase the tensile strength of the vertebrae
Describe the sections of the intervertebral discs and the role of each in load absorption.
Annulus fibrosis: made of CT, able to withstand compressive load
Nucleus pulposus: gel composed of water
- Nucleus puts pressure on annulus with load and the annulus keeps the nucleus in place
What happens to the load absorption if the disc starts to degenerate?
decreased ability to absorb load, happens when there is repeated movement and action at the joint
What is the type of movement that can occur at the cervical spine?
C0-C1 = flexion and extension
C1-C2 = rotation
C3-C7 = flexion/ext, rotation and lateral flexion (facets at 45o for increased flexion and extension)
What is the cause of decreased mobility of the thoracic spine?
facets oriented at 60o which leads to decreased movement and the ribs are attached which leads to decreased roational and flex/ext abilities
Describe the movement that occurs in the lumbar spine?
large amounts of flexion
- built for stability
Describe the movement of the intervertebral disc when the spine undergoes flex/ext, rotation?
extension: compression of the posterior part of the disc
forward bending: compression of the anterior part of disc
lateral bending: compression on the same side of the disc
What are the purposes of the muscles that attach to the spine?
Dynamic stability, large movement of the trunk and limb, maintenance of posture
What are the muscles of the trunk?
Abdominals, multifidis, erector spinae, psoas major and minor, quadratus lumborum, deep neck flexors
What is the role of abdominals in regards to the spine?
provide stability to the lumbar spine
- increase intra-abdominal pressure
What is the role of the multifidus?
stabilize the spine
- cause flexion and increase compressive forces in the lumbar spine
What are the muscles of the erector spinae group and what is their action?
iliocostalis, longissimus and spinalis
- cause trunk extension from a flexed position
What is the role of the psoas major and minor?
flex the trunk and hips
- increases intradiscal pressure on lumbar spine
Role of the quadratus lumborum?
Unilateral: lateral bending of trunk
Bilateral: trunk extension
Role of deep neck flexors?
stabilize the head, flex the head, proprioception and stabilize the cervical spine
Describe the movement of anterior and posterior pelvic tilt in regards to the ASIS and PSIS.
Anterior: ASIS moves downwards, PSIS moves upwards
Posterior: ASIS moves upwards, PSIS moves downwards
