Physiological Basis Of Muscle Disorders Flashcards
What are the two types of muscle disorders
Genetic
Non-Genetic
What are the different types of Genetic Muscle Disorders
Muscular dystrophy Storage myopathy Congenital Myopathy Familiar Periodic Paralysis Mitochondrial Diseases
What are the different types of Non Genetic muscle disorders
Myasthenia Gravis Lambert- Eaton Syndrome Inflammatory Muscle Disease Drug Disorder Hormonal Disorder
What are the known causes of muscle disorders
Injury or overuse Genetics Some cancers Inflammation Nerve diseases that affect muscles
Give examples of muscle disorders due to injury or overuse
Sprains- stretched or torn ligaments
Strains- stretched or torn muscles or tendons
Cramps and tendinitis
Give an example of muscle orders due to genetics
Muscle dystrophy
Give examples of muscle disorders due to some cancers
Give the type of muscles each cancer effects
Leimyoma (fibroids) and leimyocarcinoma (smooth muscles)
Rhabdomyoma (skeletal muscles)
Give an example of a muscle disorder that is affected by inflammation
Myositis
Give examples of nerve diseases that affect muscles
Huntington’s Disease (nerve degeneration )
Parkinson’s disease (CNS degeneration)
What is Spasticity
A condition where certain muscles are continuously contracted
What is the usual cause of spasticity
Damage to the part of the brain or spinal cord that controls voluntary movements
Spasticity can interfere with Normal movement, speech and______
Gait
What two diseases do 80% of patients experience spasticity
Cerebral palsy, multiple sclerosis
True or false, paralysis is only local
False, paralysis can be local or widespread
What is the cause of paralysis
Fault my communication between brain and muscles
Term used to describe Paralysis of the lower half the body, including both legs
Paraplegia
Term used to describe paralysis of the arms and legs
Quadriplegia
What is the main cause of paralysis
Strokes
Injury to spinal cord or broken neck
What are other causes of paralysis
Bell’s palsy (affects muscles in face)
Polio
What is the most common cause of muscular dystrophy
Gene mutation in the muscle protein dystrophin
How is muscle dystrophy characterized
Muscle wasting and weakening
The muscles breakdown and are replaced by _______
Fatty Deposits
Give examples of muscle dystrophy
Becker’s MD
Duchenne’s MD
In Becker’s MD, Dystrophin is ______, while in Duchenne’s MD Dystrophin is ________
Reduced
Absent
__________, causes progressive muscle weakness and fatigability.
Can be fatal by age 30/40
Myofibre necrosis
_________, refers to a group of hereditary muscle disorders caused by specific enzymatic defects due to defective genes
Metabolic Myopathy
What syndrome is an example of Metabolic Myopathy
McArdle’s Syndrome (myophosphorylase deficiency)
What phenomenon is seen in McArdle’s Syndrome
Second wind
What kind of genetic disorder is seen in McArdle’s Syndrome
Autosomal Recessive
McArdle’s Syndrome causes an inability to breakdown _______, hence defect in sugar metabolism
Glycogen
What disease causes a prolonged relaxation after voluntary contraction
Clinical Myotonia
What is the cause of clinical myotonia
Abnormal Na+ or CL- channels
What muscle disorder is associated with the warm up phenomenon
Clinical myotonia
Clinical Myotonia can be triggered by ________ or made worse after ______
Cold or fatigue
Periods of rest
What are the two types of congenital myotonia
Becker’s and Thomsens Disease
True or false, both Becker’s and Thomsens Disease appears in childhood but Becker’s later
True
Congenital Myotonia causes severe muscle stiffness mostly in males
True
True or false, unlike Becker’s, Thomsen’s disease causes temporary attacks of muscle weakness in arms and hands brought on by movements after rest,l
False It is Becker’s
True or false, mild permanent muscle weakness may develop over time in clinical Myotonia
True
What Type of genetic disorder is familial periodic paralysis
Rare autosomal dominant condition
What disorder causes sudden episodes of flaccid paralysis and loss of deep tendon reflexes and failure of muscle to respond to electrical stimulation
Familial periodic paralysis
Where does Familial Periodic paralysis mostly affect
Limbs
In familial periodic paralysis, weakness is often brought on by
Excercise
Eating too much or too few carbohydrates
What are the four types of familial periodic paralysis
Hypokalaemic
Hyperkalaemic
Thyrotoxic
Anderson-Tawil Syndrome
What causes Hypokalaemic
Mutation in alpha-subunit of the voltage-sensitive muscle calcium channel (mostly)
sodium channel gene
What causes Hyperkalaemic
Mutation in the gene that encodes the alpha- subunit of the skeletal muscle sodium channel
What causes thyrotoxic
Mutations and affected electrolyte channels in the thyrotoxic form are unknown but this form usually involves hypokalemia and is associated with symptoms of thyrotoxicosis
What causes Anderson- Tawil Syndrome
Defect of inward- rectifying potassium channels; patients can have a high, low or normal potassium level
Each form of familial periodic paralysis involves what two ways
Different genes
Electrolyte channel
What is the etiology of Lambert- Eaton Syndrome
Antibodies against the presynaptic calcium channels of the neuromuscular junction
Decreased acetylcholine release
What is the sign/symptom of Lambert Eaton
Proximal muscle weakness that improves with repeated use
Lambert Eaton Syndrome is associated with what Syndrome
Paraneoplastic Syndrome eg small cell lung cancer
