Spinal cord pathology Flashcards
What is the difference between afferent and efferent divisions of the nervosu system
- Afferent = sensory - brings info into the NS
- Effernt = motor - carries informaiton out of the NS and effects change
What does the CNS consist of
Spinal cord, brain stem, cerebellum, cerebral hemispehres
Describe the Spinal cord
- Facilitates transmission of neural impulses from the brain stem to the rest fo the body
- Extends from medulla oblongata
- 42-45cm in length
- Divided into cervical, thoracic and lumabr regions.
- 31 pairs of spinal nerve both sensory and motor travelling alogn ascending and desensing pathways.
- Beyond the first lumbar vertebra te cor dbecomes a bundle of nerves.
Spinal cord Nerves
- Cervical nerves (8pairs) - Head/neck, delotoids/biceps, tricepts, hands
- Thoracic Nerves (12pairs) - chets muscles, abdominal muscles
- Lumbar (5pairs) - leg muscles
- Sacral (5pairs) - bowels, bladder
- Injuries: To cervical (life threatening-the hgiher the worse), thoracic (legs, pelvic organs/bp), lumbar (Both legs/incontinence)
Some examples of psinal cord pathology causes
Damage can be temporary or permanent. 80% injuries occur in males
- Infections such as meningitis and polio
- Autoimmune diseases
- Oesteoporosis/ arthritis
- Degenerative diseases- spinal muscular atrophy
- Tumours - Metastatic. Can reusltin spinal cord compression (10% of patients with spinal cor dmetastases), signficiant neurological complciations.
Common types of spinal cord injury
- Cervical spine from hyperextension or hyperflexion of neck
- Dislocation of vertebrae may crush, compress or reduce blood supply to the neck
- Compression fractures
- Penetration injuries (stabbing or bullet wounds).
Complete vs partial transection in spainl cord injury
- Complete transaction or crush = loss of motor and snesory functions at and below the level of injury
- Partial transection or crush may allow some recovery of function
- Bruising can reuslt in tmeporayr loss of function when mild oedema and bleeding impair function.
Dmaage tends to lead to local bleeding and inflammation to develop - creating additional pressure
Temporary is bruising and permanent is ocmplete severing (transection) of crushing of the cord
Also known as complete or incomplete complete = no sensation
Most common causes of spinal cord injuries
Spinal cord injury - acute, secondayr and chronic effect (what type of affectd these are)
- Acute effects - seconds to minutes after injury
- Secondary effects - minutes to weeks after injury
- Chronic - months to years after injury
Temporary is bruising and permanent is ocmplete severing (transection) of crushing of the cord. TIME = neurons
- Hypotension – trauma – vasodilation due to neurogenic shock
- Bleeding and swelling put extra pressure on the cord impairing function and reducing blood supply
- Spinal shock – first 24 hours – impaired oxygen to spinal cord
- Free radicals – breakdown lipid in cell membranes
- Too much calcium can damage the cell and
- Apoptosis – delayed calcium influx can trigger cell death – cell shrinks and is engulfed by other cells.
SYmptoms of SPinal cord injuries
- Limb control – depends on two factors: Injury location and severity
- The lowest part of the spinal cord that remains undamaged after an injury is referred to as the neurological level of injury
- Pale and numbness
- Inability to move
- Exaggerated reflex activities and spasms
- Changes in sexual function and fertility
- Inability to feel pain
- Muscle spasm
- Loss of bladder and/ or bowel control
- Difficulty breathing
Ability to contorl your limbs after a spinal cord injury depends on two factors. The lowest part of spinal cord that remains undamaged after injury is referred to as neuro.
Severity of injury is often called completeness
SCI epidemiology
Stages of SPinal cord injury
- Early stage - spinal shock - all neuro activity ceases at, below and slightly above level of injury
- Rceoveyr stage - gradual return of reflex activity below level injury
No signals in spinal shock – skeletal muscle, sensory, autonomic systems (Blasser and bowel)
May include a loss of vasomotor control – BP, temperature.
Types of Paralysis
- Paraplegia = paralysis of lower limbs (T1 and below)
- Hemiplegia = bilateral paralysis (Hemispheric brain damage)
- Quadriplegia = paralysis of all four limbs (C4 and above)
Treatment spinal cord injuries
- Medication - IV methyprednisolone in acuet management, decreases inflammation
- Immobilisation - traction to stabilise the spine
- Surgery - removal of fragment of bone, foreign objects, herniated discs, fractured vertebrae
- New tech - stem cells
New TECH: Electrical stim devices (to prodcue actions), modern wheelchairs (lightweight, electric), computer adaptions, electronic aids to daily living (voice controlle dequipment).
Treatment example:
- regen is possible of NS.
- Activity based recovery - patterned neural activity might stimulate CNS to become more functional as it does durign development.
- Funtional electrical stimulation FES = specially designed recumbent bicycle system that uses computer controlled electrodes palcd on patients legs to stimulate leg muscles in specific patterns. Paralysed person can rotate bicycle pedles. Builds Builds muscle mass and bone density, reducign spasticity and CV workout.
Neurological classification of spinal cord injury
Standard classification American Spinal Injury Association ASIA:
- Motor function - vol control of muscles
- Sensory function - sense of touch, sensation of heat/cold/pain or pressure
- Sense of where limbs are
Steps in classification: Determine
- Right/Left sensory levels
- Right/left motor levels
- Single neurological level - lowest segment where motor/sensory function normal
- Determine whether injury is complete or incomplete
