Lsp and pelvis

Question 1

Impact altered spinal curves can have on overall mechanics

Question 2

Form force closure

Answer 2

Pelvis- shapes fit together and form closure to support
Sacrum and ilium each have one flat surface and one ridged surface which interlock together, promotes stability

Force closure
Contraction of muscles and ligaments hold the bones together and keeps them stable

Question 3

Force coupling

Answer 3

Pivot point where it has multiple forces pulling in multiple forces to allow rotation
Pivot point around acetabulum
Key muscles groups- Lip erector spine, QL, hamstrings, hip flexors, poses, abdominal walls

Question 4

Cylinders

Answer 4

Provides same tensile compression strengths as well as flexibility
Copes with multiple vectors of movements

Question 5

How does spine cope with gravity
Impact of centre of gravity on spinal curves

Answer 5

Csp lies central to plumb line to support head
Tsp lies posteriorly to make room for internal organs
Lsp lies centrally to support weight of trunk

When gravity lowered in space the discs are able to hold more fluid making them larger= more spaces between vertebra

Question 6

Gravity affecting bone

Answer 6

Gravity applied to skeletal system maintains healthy bones
Maintain certain density to support body in daily function

Question 7

Structure of intervertebral disc

Answer 7

Disc separates vertebra
Disc= 20-25% of spinal column
Peripheral post aspects- innervated by intervertebral nerve
Laterally- innervated peripherally by branches of ant + grey rami
P sensitive structures- vertebral body, nerve root, cartilage of facet Jt ALL and PLL

Question 8

Function of intervertebral disc

Answer 8

Majority water= non-compressible fluid- allows preloading and resistance to compressible forces
Layering of annulus= tolerance of asymmetrical loading (esp torsion)
Annulus + nucleus pulpous= structural integrity= inc stabilisation
Combo of gel-filled nucleus pulpous + fibrous nature of annulus= adaption/accommodation of spinal curve changes

Question 9

Impact of altered angulation of pelvis has on spinal mechanics and curves

Question 10

Impact scoliosis has on spinal mechanics

Answer 10

Spinal shear and compression are inc
Overgrowth of ant aspect of spine and rotation of vertebral bodies
Trunk stability is dec due to muscular difference on concave side of spine compared to convex side

Question 11

Impact Scheurmans has on spinal mechanics

Answer 11

Inc thoracic flexion, due to inc kyphosis
Tends to cause flattened Lsp or hyper extend neck, or both
Seen in teenagers

Question 12

Info about spondylosis

Answer 12

Spony- spine, Osis- degeneration
Structures involved- vertebra, discs, facets, capsules, muscles and ligaments

Question 13

Initial phase of spondylosis

Answer 13

Degeneration of disc leading to reduced disc height
Approximation of facets and ligamentous laxity (more chance of facet irritation as closer, laxity= instability= more episodes of acute P due to more irritation)
Acute episodes of P and muscle spasm

Question 14

Middle stage of spondylosis

Answer 14

Segment instability due to ligamentous laxity
Chronic muscle fatigue (muscle takes pressure off ligament, not meant to support so becomes weak)
Hypoxia and micro trauma due to inc stabilising effect from muscles
Constant low grade ache
Acute episodes of P and muscle spasm

Question 15

Later stage spondylosis

Answer 15

Osteophyte formation around facets and vertebral bodies
More episodes of acute P along with constant ache from overuse of paraspinal muscles

Question 16

Weight bearing forces v ground reaction

Answer 16

Weight bearing down through femur- trabecular to withstand breakages
Ground reaction forces- up through femur

Question 17

Trabecular

Answer 17

Important for tensile strength