Amyotrophic Lateral Sclerosis (ALS).pdf

Amyotrophic Lateral Sclerosis (ALS)  Amyotrophic Lateral Sclerosis (ALS) – A = absence of – Myo = muscle – Trophic = nourishment – Lateral = side (of spine) – Sclerosis = hardening or scarring Lou Gehrig Is a pro...

Amyotrophic Lateral Sclerosis (ALS)  Amyotrophic Lateral Sclerosis (ALS) – A = absence of – Myo = muscle – Trophic = nourishment – Lateral = side (of spine) – Sclerosis = hardening or scarring Lou Gehrig Is a progressive, fatal, neurodegenerative disease (1903-1941) caused by the degeneration of motor neurons, motor cranial nerve nuclei, the nerve cells in the central nervous system that control voluntary muscle movement Causing upper and lower motor neurons degeneration. Which result in muscle atrophy and weakness (amyotrophic).  Epidemiology 5,600 Americans are diagnosed with ALS each year Nearly 10% of ALS cases are familial; transmitted in an autosomal dominant fashion. – about 90% of all cases occur randomly (sporadic) Average age of onset is 55 years – 56 for sporadic; 46 for familial Incidence is 2-5 per 100,000 Occurs in all races and all around the world at near equal rates  Epidemiology Men get ALS more than women (1.3 to 1 ratio) – After age 60, ratio of men to women nearly 1 to 1 – 80% of cases begin between ages of 40 to 70 Longevity: – 50% live at least 3-4 years after diagnosis – 20% live 5 or more years – 10% survive more than 10 years after diagnosis  Etiology Unknown - but we have several hypothesis: – Autoimmune disease – Viral infection – Excessive of extracellular glutamate (Glutamate toxicity) – Toxic: an increase in lead and aluminum levels; an increase in calcium and magnesium levels. – Genetic (10%): mutation of the superoxide-dismutase (SOD1) gene in chromosome 21.  Pathology Upper Motor Neurons Lesion Neurons demyelination and gliosis (formation of a glial scar ) and axonal loss of corticospinal and corticobulbar tracts (lateral sclerosis). Causes degeneration of Betz cells in the motor cortex which results in UMN symptoms – at level of internal capsule and cerebral peduncles in the midbrain – Leads to spasticity, hyperactive reflexes  Primary Lateral Sclerosis (PLS) It’s same as ALS, but the degeneration occur only in the Upper Motor Neurons (corticospinal and corticobulbar tracts) Causes: 1. Spasticity in axial, limb and bulbar muscles: (The muscles that control the speech, chewing and swallowing) 2. Hyperactive reflexes 3. Pathologic reflexes 4. Spastic dysarthria and dysphagia  Pathology Lower Motor Neurons Lesion Progressive Bulbar Palsy (PBP) Degeneration of bulbar motor nuclei (LMN) of cranial nerves V, VII, X, XI, XII Spinal muscular atrophy (SMA) Degeneration of spinal anterior horn cells, roots & nerves (LMN) Leads to atrophy and fasciculation  Progressive Bulbar Palsy “Bulb” refers to the brainstem Symptoms – Slurring of voice (dysarthria) – Difficulty chewing – Difficulty swallowing (dysphagia) – Shortness of breath - with exertion, later at rest Signs – Weak, fasciculating tongue – Jaw and/or neck weakness – Decreased forced vital capacity – Brisk jaw jerk  Symptoms of ALS First symptom is weakness of one or more muscles and the weakness spreads to other areas of the body. Muscle weakness of lower extremities > upper extremities – Typically the distal muscles are involved before the proximal muscles. – Flexors tend to be weaker than extensors. – Impairment of use of arms, legs Muscle twitching, cramping – Especially muscles in hands, feet Weakness in head turning or even inability to support head while sitting. muscles of speech, swallowing or breathing ALS rarely affects cognitive functions  UMN UMN symptoms include: hyperreflexia, spasticity and +ve Babinski. Bladder and bowel are almost always spared. Oculomotor nuclei are almost always spared. Cognitive functions are not affected. About 20% of patients have sensory impairment and abnormal (SSEP).  Treatment of ALS Medication: Riluzole – Antiglutamate agent – Prolonged survival - modest benefits – to slow progression of disease Baclofen and Tizanidine for spasticity NSAIDs for general discomfort Tramadol for pain Antidepressants  Treatement Nutritional Support Breathing Assistance Dietitians can design diets Masks or nose inserts that are nutritious and easy to swallow Use of full-time Mechanical ventilation may also be necessary Gastrostomy tube (Feeding tubes)  Treatment Physical Therapy Speech Therapy Low Impact exercises for Techniques to speak louder muscle tone and ROM as and more clearly long as possible Passive ROM to prevent Use of non-verbal contractures communication and speech aids after ability to speak is lost