Section 35: Spine Structural Components 35-1 Human Spine Human - PowerPoint PPT Presentation

Section 35: Spine – Structural Components 35-1

Human Spine Human Spine • Functions to protect the spine transfers Functions to protect the spine, transfers loads from head and trunk to pelvis • 24 vertebrae that permit motion in all 3 • 24 vertebrae that permit motion in all 3 planes • Stability comes from: St bilit f – Intrinsic: intervertebral discs and ligaments – Extrinsic: muscles 35-2 From: Iatridis

From: Peeler 35-3

From: Yoon 35-4

Cervical Spine Cervical Spine • Seven vertebrae • C 1-7 • More flexible • Supports the head • Wide range of motion – Rotation to left and right R t ti t l ft d i ht – Flexion • Up and down p • Peripheral nerves – Arms – Shoulder, Chest and diaphragm 35-5 From: Ziv

Thoracic Spine Thoracic Spine • Mid-back or dorsal region Mid back or dorsal region • Twelve vertebrae – T 1-12 T 1 12 • Ribs attached to vertebrae • Relatively immobile • Peripheral nerves e p e a e es – Intercostal 35-6 From: Ziv

Lumbar Spine Lumbar Spine • Lower back Lower back • Five vertebrae – L 1-5 L 1 5 • Carries the the weight of the upper body – Larger, broader • Peripheral nerves p – Legs – Pelvis 35-7 From: Ziv

Sacral and Coccygeal region Sacral and Coccygeal region • S acrum S acrum – Triangular structure – Base of the spine Base of the spine – Connects spine to pelvis – Nerves to pelvic organs Nerves to pelvic organs • Coccyx – Few small bones – Remnant of tail 35-8 From: Ziv

From: Peeler 35-9

From: Iatridis 35-10

From: Peeler 35-11

From: Iatridis 35-12

From: Peeler 35-13

Intervertebral Disc Intervertebral Disc • Soft fibro-cartilaginous cushions Soft fibro cartilaginous cushions – Between two vertebra – Allows some motion Allows some motion – Serve as shock absorbers • Total – 23 discs Total 23 discs • ¼ th of the spinal column's length • Avascular • Avascular • Nutrients diffuse through end plates 35-14 From: Ziv

Intervertebral Disc Anatomy Intervertebral Disc Anatomy • Spongy center Spongy center – Nucleus pulposus • Surrounded by a Surrounded by a tougher outer fibrous ring – Anulus fibrosus 35-15 From: Ziv

Anulus Fibrosus Anulus Fibrosus • Strong radial tire–like structure Strong radial tire like structure • Series of lamellae • Concentric sheets of collagen Concentric sheets of collagen fibers – Connected to end plates p – Orientated at various angles – Under compression • Become horizontal • Encloses nucleus pulposus 35-16 From: Ziv

From: Yang 35-17

From: Iatridis 35-18

From: Iatridis 35-19