Spine

Vertebrae

The individual bones that make up the vertebral column, comprise a total of 33 vertebrae in a typical human spine. These bones are categorized into five regions: cervical (7), thoracic (12), lumbar (5), sacral (5 fused), and coccygeal (4 fused). The vertebrae provide structural integrity, protect the spinal cord, and facilitate movement and flexibility of the spine. Each vertebra consists of a vertebral body, vertebral arch, and various processes for muscle attachment and articulation with adjacent vertebrae.

Cervical Vertebrae

The uppermost part of the spine, consisting of 7 vertebrae (C1-C7), allowing for a range of motion including lateral flexion and extension

Atlas (C1)

The first cervical vertebra supports the skull and allows for flexion and extension but does not have a vertebral body. Rotates on C2

Axis (C2)

The second cervical vertebra features the dens, allowing for rotation of the atlas and thus the head. allows for C1 to rotate and pivot

Intervertebral Disc

A fibrocartilaginous joint between adjacent vertebrae that acts as a cushion and provides flexibility to the spine. It prevents grinding between the vertebraes

Annulus Fibrosis

The outer layer of the intervertebral disc, it is arranged in 15-25 concentric layers with alternating layers with different angles to create a strong configuration for strength and stability. It is made of collagen fibres. The outer 1/3 of the annulus fibrosis is innervated and has a blood supply. It can stretch have have slack on opposite sides of the disc. During rotation the fibres that run counter to the direction of movement are stretched while the others are relaxed, this causes max tension and the nucleus puposus is compressed. Rotation compress the spinal disc and this is why flexion with axial rotation tears the annulus and drives the nucleus back leading to dis herniaiton.

Nucleus Pulposus

The inner core of the intervertebral disc, is made of gel-like material that provides support and shock absorption. it is incompressible so applied load creates an outward pressure in all directions. Sitting puts the most force on the disc than standing. Laying down on your back as the least amount of force

Sciatic Nerve

A major nerve that arises from the lumbar and sacral spine (L4-S3) and travels down the leg, often associated with sciatica.

Spinous process

• Projects posteriorly

• A series of levels for muscles of postures and muscles of active movement

• Protects the spinal cord

  
  

Lateral (transverse) process

• Articulations with ribs (thoracic spine)

• Facet Joint

Pedicle

Bony process that projects backward from the body of the vertebrae and connect with the laminae

Lamina

• Bone process on either side of the neural arch

• Project backward and inward from the pedicles

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Facet Joint

• Joint in-between vertebrae excepts C1 and C2

• Flex/extension

• Lateral flexion and rotation

Cervical Vertebrae and Nerves

7 vertebrae, allows for lateral flexion and extension, 8 cervical nerves. C8 is between C7 and T1

Thoracic Vertebrae and Nerves

12 vertebrae’s, allows for more rotation and some lateral flexion and extension. 12 thoracic nerves

Lumbar Vertebrae and Nerves

5 lumbar vertebrae, allows for lateral flexion but no rotation, there’s 5 lumbar nerves

Sacral and Coccygeal vertebrae and nerves

5 sacral vertebrae, 5 sacral nerves, 1 coccyx vertebrae, 1 coccygeal nerve

Occipitocervical Joint, C1

Flexion and extension is 50 degrees, rotation is 4 degrees and lateral bend is 8 degrees

Atlantoaxial joint C1-C2

Flexion and extension is 10 degrees, Rotation is 50 degrees and lateral bend is 0 degree

Subaxial Cervical Spine

Flexion and extension is 50 degree, Rotation is 50 degrees and lateral bend is 60 degree

Thoracic Spine

Flexion and extension is 75 degree, rotation is 70 degree and lateral bend is 75 degrees

Lumbar Spine

Flexion and extension is 85 degree, rotation is 10 degrees and lateral bend is 30 degrees

Anterior and Posterior Longitudinal ligaments

Connect vertebral bodyies

Ligament flava

Connect laminae, increase in elastin

Intertransver ligaments

Connects transverse

Interspinous and supraspinous ligaments

Connect spinous process

Muscles

Erector spinae is superficial, transversospinalis is deep

Flexion and extension in the spine occurs at

Cervical, thoracic and lumbar regions

Lateral flexion occurs at

cervical, lumbar and minimally at thoracic

Rotation occurs at

Cervical and thoracic

Transversopinalis Muscle Group

• Bilateral contraction

  • extends the spine

• Unilateral contraction

  • Lateral flexion

  • Rotates the vertebral column to the opposite side

  • If the muscle contracts on the right, it will turn your head and spin left

  
  

General causes and Symptoms for back injuries

Causes

• Congenital predisposition

• Previous trauma

• Mechanical factors

  • Poor posture (lifting, bending)

  • Obesity

• Acute or repetitive trauma

 

Effects

• Pain, tenderness, spasm, restricted ROM

• Neurologic Ssx

  • Radiating pain, sciatica

  • Weakness, numbness, absent DTR

Sprain and Strains

• Hx

  • Twisting or lifting

  • Recurrence is common

• Ssx

  • Pain and tenderness

  • Muscle spasm (delayed onset)

  • Restricted ROM (early or delayed onset)

  • Increase warmth

  • If any neurologic Ssx are pressure, assume fracture dislocation or disc injury, stabilize and transport to hospital

Tx

• Rest, supine, no more than 2 days

• NSAID/pain meds

• Cold therapy first and heat later

• Physio and massage

• Comprehensive rehab program

  • Flexibility, strengthening and task specific

• Correct predisposing factors (posture)

• Gradual return to activity

Lumbar Disc Herniation

• Nucleus pulposus breaks through annulus fibrosis

• Often occurs between L4/L5 and L5/S1

• Vulnerable between ages 30 to 50 as elasticity and water content of nucleus pulposus decreases with age

• can be from forward bending and placing abnormal strain on lumbar region

  
  

4 stages of Lumbar Disc Herniation

Disc protrusion

• Bulging disc

• Cracks in the annulus fibrosis begin to appear

Prolapsed disc

• Nucleus pulposus moves completely through annulus fibrosis

Extruded Disc

• Nucleus pulposus moves into spinal canal and comes in contact with a nerve root

Sequestered Disc

• Portion of nucleus pulposus separated from disc and begins to migrate in spinal canal

Intervertebral Disc Disease (herniation)

Hx

• From twisting and lifting

• Herniation of nucleus pulposus

• Compression of nerve root(s) or spinal cord

Effect

• Pain and tenderness

• Muscle spasm (delayed onset)

• Restricted ROM (early or delayed onset)

• Increase warmth

• If any neurologic Ssx are pressure, assume fracture dislocation or disc injury, stabilize and transport to hospital

• Instability

• Osteoarthritis, osteophytes, stenosis

Tx

• Conservative if possible

  •  

  • Rest, supine, no more than 2 days

  • NSAID/pain meds

  • Cold therapy first and heat later

  • Physio and massage

• Surgery for discectomy, laminectomy, or fusion

Fractures

• Axial load

  • Cervical spine becomes compressed with lots of force, head into boards at hockey or helmet to helmet in football

• Ssx

  • Point tenderness, decrease ROM

  • Pain in neck, chest and extremities

  • Numbness/weakness in trunk/limbs

• Tx

• Stabilize, c-spine collar, spine board

• If unconscious assume c-spine injury

Spine Treatment

• Key is balance

  • Demands with functional capacity

  • Expectations with realistic goals

• Main Points

  • Take time to heal and rest, most important

  • Cold, heat, NSAIDs, brace

  • Physio, massage therapy, chiro

  • Rehab, indefinite

  • Correct predisposing factors

  • May need to change job or sport

Mcgil Big 3

• Strengthens the muscles that stabilize the spine and build endurance

  • Bird dog

  • Trunk raise

  • Side plank

• 10 seconds of activity

• 2 seconds rest