spinal cord injuries - wordpress.comm ass reflex, also called autonomic hyperreflexia , usually...

SPINAL CORD INJURIES

Dr. Ayisha QureshiProfessor

MBBS, MPhil

ASCENDING TRACTS

• FOR CONSCIOUS PERCEPTION:1. Anterolateral system2. Dorsal Column Medial Lemniscus system

• FOR UNCONSCIOUS PERCEPTION:1. Spinocerebellar (anterior and posterior)2. Spino-olivary3. Spinotectal4. Spinoreticular

WHITE MATTER OF SPINAL CORD

ASCENDING TRACTS DESCENDING TRACTS

SPINAL CORD INJURIES

Actor Christopher Reeve (who played SUPERMAN) suffered spinal cord injury in 1995 when he fell during a horse-riding accident and

died in 2004 after being confined to the wheelchair for 9 years.

SPINAL CORD INJURIES leading to SPINAL CORD DYSFUNCTION

A. Complete transectionB. Incomplete transection

C. HemisectionD. Diseases of spinal cord.

1. Complete Transection of the Spinal Cord

Complete Transection can occur due to bullet injury, an accident causing dislocation of spinal cord or occlusion of

blood vessels. The effects occur in three stages:1. Stage of spinal shock.2. Stage of reflex activity.3. Stage of reflex failure.

CAUSES TRAUMATIC INJURIES• Motor vehicle accidents• Football• Falls• Gymnastics• Violence• Diving into shallow water

Spinal cord injuries affect more men than women. The majority of people who sustain a spinal cord injury are young adults between the ages of 16 and 30 because of riskier behaviour.

NON-TRAUMATIC INJURIES/ILLNESSES• Cancer Osteoporosis• Multiple sclerosis• Inflammation of the spinal cord• Arthritis

A severe spinal cord injury is followed by multiple progressive symptoms that are

collectively called Spinal Shock:

Thus, Spinal Shock is defined as the transient depression or abolition of reflex activity below the level of an

acute spinal cord injury or transection.

STAGE OF SPINAL SHOCKLoss of all neurological activity including motor, sensory,

reflex and autonomic function

STAGE OF REFLEX ACTIVITY Return of the reflexes, flexor followed by extensor.

Babinski +ve. Limbs cannot support the weight of the body.Mass Reflex seen.

STAGE OF REFLEX FAILUREGeneral infection or toxemia develops. Reflexes become more difficult to elicit. Muscles become extremely flaccid

and show wasting.

Arterial blood pressure fallsinstantly and drastically—sometimes to as low as 40 mm

Hg—thus demonstrating that sympathetic nervous systemactivity becomes blocked. BP ordinarily returns to normal

within a few days.

The first reflexes to return are the stretch reflexes, followed in order by the more complex reflexes: flexorreflexes, postural antigravity reflexes, & remnants of

stepping reflexes.

The sacral reflexes for control of bladder and colonevacuation are suppressed for the first

few weeks after cord transection, but in most casesthey eventually return.

What is the Mass reflex?

Mass reflex, also called autonomic hyperreflexia, usually follows a spinal cord injury in the cervical or higher thoracic region, results from an

abnormal massive sympathetic discharge precipitated by various stimuli that are innocuous in neurologically normal persons.

A widespread reaction can be elicited by distension of the bladder, urologic procedures or skin irritation over the lower limbs or the anterior abdominal

wall. The effects are: 1. Strong flexor spasms of the lower limbs.2. Evacuation of urinary bladder & colon.

3. Hypertension.4. Bradycardia.

5. Profuse sweating.

2. Incomplete Transection of the Spinal Cord

If the spinal cord is gravely injured, but does not suffer complete division, then it is called incomplete

transection. Similar stages are seen as with the complete transection, however, clasp-knife rigidity is

seen and mass reflex is not seen.

3. Hemi-section of the Spinal Cord BROWN-SEQUARD SYNDROME

Lesion involving one lateral half of the spinal

cord (right or left) is called a Hemi-section.The signs & symptoms

which occur after hemi-section of the spinal cord

constitute the Brown-Sequard syndrome.

4. Diseases of Spinal Cord

a. Syringomyeliab. Tabes Dorsalis

c. Multiple Sclerosis

SYRINGOMYELIA

It is a rare and chronic disorder in which fluid filled cysts form around the spinal cord.

As the cysts expand, they compress or damage the spinal cord esp. the gray matter of the anterior and posterior horns of the spinal cord and the fibers crossing in the

anterior gray commissure.

1. Central Canal area affected : Loss of temperature, pain & crude touch sensations only, due to lesion of the fibers crossing through the anterior gray commissure. Fine touch sensation is not affected as DCML is not affected.

2. Unilateral lesion: effect occurs only on the same side.3. Posterior gray horn affected: All the sensations are

lost. 4. Anterior gray horn affected: Flaccid paralysis of

muscles. In later stages, both pyramidal and extrapyramidal tracts are also involved, if the disease spreads to white matter.

TABES DORSALIS It is a late manifestation of untreated syphilis or

neurosyphilis and is also known as locomotor ataxia.

It causes degeneration and demyelination of posterior (sensory) nerve roots and dorsal columns of the white

matter.

• Impairment and loss of all sensations.• Paresthesia (an abnormal sensation, typical tingling or pricking,

caused chiefly by pressure on or damage to peripheral nerves)• Loss of proprioception, vibration and discriminative touch• Loss of reflexes in the legs • Romberg’s sign Positive • Hypotonia• Loss of sensations, particularly pain sensation leads to deformities

of joint. There is no proper support and movements and the joints become uncontrolled. It is called Charcot joint.

• Ataxia (lack of coordination of movements).• Normal movements like walking also become clumsy. The gait is

awkward. Every movement of the limb is exaggerated while walking. Patient keeps the leg apart, raises the leg very high and stamps it down forcibly. This is called stamping gait.

• Urinary bladder: If sacral segments are affected in tabes dorsalis, the smooth muscles of the urinary bladder become hypotonic. Micturition reflexes are lost. And the urinary bladder becomes atonic bladder.

Multiple Sclerosis

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MULTIPLE SCLEROSISGOING, GOING, GONE…..

Multiple Sclerosis (MS) is an auto-immune disease in which nerve fibers in various locations throughout the nervous system lose their myelin. This leads to disruption of nerve impulse conduction.

Multiple Sclerosis: Cause:Exact cause is still unknown. It is suspected that a foreign agent such as a virus alters the immune system so that the antibodies of the immune system mistakenly attack and destroy Schwann cells, thus also destroying the myelin sheath. The destroyed part is replaced with scar tissue. When myelin sheath is destroyed, the nerve impulses travelling along the nerve fibers slows down. When more and more nerves are affected, the person experiences interference with functions that are controlled by the nervous system such as speech, memory, vision, walking etc.

Signs & symptoms:Patchy destruction of myelin in the CNS→ slow & abnormal conduc on of the nerve

impulses in the neurons↓

1. Visual disturbances2. Tingling & numbness

3. Muscle weakness & Fatigue4. Gradual paralysis

5. Bladder & bowel problems

Myelin destruction in MS

DIAGNOSIS & TREATMENT DIAGNOSIS

Physicians, particularly neurologists, take detailed histories and perform complete physical and neurological examinations.• MRI• Nerve Conduction Studies• Cerebrospinal fluid exam (spinal tap,

lumbar puncture)

TREATMENT• Debilitating disease but not fatal. The

quality of life is affected…. Death may occur when the paralysis reaches the respiratory muscles and the person cannot breathe.

• No treatment as yet.• Only symptomatic treatment.1. Immunosuppressive therapy: as

autoimmune disease so you try to suppress the immune system to prevent further damage.

2. Corticosteroids3. Alternative therapy: as homeopathy,

ayurvedic treatment etc.

DECEREBRATE VS DECORTICATE

DECEREBRATE RIGIDITY • Decerebrate animal is one

in which the brain has been transected between the superior and inferior colliculus at the level of the midbrain. And the influence of the Cerebrum along with the upper brainstem is lost. has been completely removed.

DECORTICATE RIGIDITY • Decorticate animal is one in

which the entire cerebral cortex is removed but the brainstem and areas below are left intact.