Pathology Lesson 2 Flashcards
In myopathy, what three things are affected?
strength tone and bulk
Weakness in myopathy is usually ______ and _____ ?
symmetrical and proximal
In myopathy, what is decreased?
tone and reflexes
Atrophy and hypertophy is associated with what disease?
myopathy
After a binge, there is an acute attack of what three things?
Muscle weakness
Pain
and swelling
What is myopathy?
disease of muscle
Alcoholic myopathy can have what three kinds of weakness?
chronic
progressive
proximal
Necrosis of individual muscle fibers is associated with what disease?
toxic myopathy
What two drugs cause toxic myopathy?
ipecac
vincristine
What three kinds of pathogens are the etiology of myositis?
viral
bacterial
parasitic
What four pathogens cause myositis?
Influenza Staph aureus Tuberclosis Trichinosis AKA -> SITT
What is the most common toxic myopathy?
alcoholic
What two forms of myositis are there?
polymyositis
dermatomyositis
Myoglobinuria means what other condition happen to the muscle?
rhabdomyolysis
Which myositis causes heliotrope discoloration around the eyes and periorbital edema?
dermatomyositis
What is an electromyography?
studies activation of motor units
What does an electromyography record?
electrical activity of a muscle
What is the mechanism of Duschenne Muscle Dystrophy?
1) defective cell membrane protein
2) failure of contractile protein attachment
3) necrosis of muscle fibers
What does an electromyography measure?
recruitment of voluntary muscle
What is Duchenne Muscular Dystrophy?
recessive, X-linked single gene defect
Muscles account for what percentage of body weight?
50%
What are three basic muscle types?
skeletal, smooth, cardiac
Give 4 characteristics of skeletal muscle
voluntary
striated
multinucleated
large
Give 5 characteristics of cardiac muscle
striated involuntary branching one location uninucleate
What are 8 functions of the muscular system?
- movement-
- maintenance of posture-
- stabilization joints
- respiration
- production of body heat
- constriction of organs-vessels
- heart beat
- “guard” orifices
MMSRPCG
Give 4 characteristics of smooth muscle
nonstriated
involuntary
sheets
uninucleate
At what age do the size and number of muscle fibers begin to decrease?
40
What is contractility?
ability of a muscle to shorten with force
What is excitability?
capacity of muscle to respond to a stimulus
What is extensibility?
muscle can be stretched
What is elasticity?
ability of muscle to recoil back to original resting length after being stretched
What is the shape of a skeletal muscle?
long and cylindrical
What kind of contractions does a skeletal muscle have?
rapid
Name the opposing movement:flexion
extension
Contraction of skeletal muscle occurs in response to what?
nerve impulse
What happens to the skeletal muscle when the nerve impulse is removed?
relaxes
Muscle tissue is constructed how?
bundles of fibers
Higher demand of muscle work requires what?
increased blood supply for increased oxygen need
How is the color of a muscle affected by blood supply?
the greater the blood supply, the darker the color
What is myoglobin similar to?
hemoglobin
Where is myoglobin found?
skeletal and cardiac muscle
What three things happen when myoglobin is released into circulation with muscle damage?
leaks potentially toxic cellular content
renal toxicity
acute renal failure
What does myoglobin transport?
oxygen
If a patient has rhabdomyolysis, what 5 symptoms may he/she present with?
MUSCLE pain
MUSCLE Cramping
Fever
Flu like symptomes
Dark urine
( M2, F2, D1 )
What are six select causes of rhabdomyolysis?
trauma exercise (status) asmaticus mult drugs (Status) epilepticus substance abuse
mneumonic:
TEAMES
What isoforms are specific for myocardial damage?
troponin
What is status epilepticus?
continuous seizure activity without pause
What is status asthmaticus?
persistent and intractable asthma
Name the opposing movement:1) flexion2) supination3) rotation to right4) eversion5) abduction
1) extension2) pronation3) rotation to left4) inversion5) adduction
Compartment syndrome can result in sequela of what? What is this?
1) Volkmann ischemic contracture
2) Volkmann ischemic contracture is decreased perfusion to organ which results in hypoxia and contraction of muscles (rigidity)
Increased venous pressure leads to what two things?
1) decreased arterial pressure (Ischemia)
2) Edema
What kind of skeletal muscle contraction maintains posture?
continuous contractions
What is compartment syndrome?
local muscle damage
What provides support for the weight of visceral organs?
layers of skeletal muscle tissue located in abdominal wall and pelvic cavity
Sphincters provide 3 somewhat kinds of voluntary control. What are they
swallowing
defecation
urination
What kind of skeletal muscle encircles openings to digestive and urinary tracts?
sphincters
Following a muscle contraction, how much of the energy is released as body heat?
about 3/4
What are two important skeletal muscle properties?
irritability and contractility
What is irritability?
ability to receive and respond to stimulus
What seven things are used in naming skeletal muscles?
SA LANDS
SHAPE ACTION PERFORMED LOCATION ADJACENT BONES NUMBER OF HEADS DIRECTION OF MUSCLE FIBERS SIZE
What is contractility?
ability to contract when adequate stimulus is received
What are three functions of fascia?
COVERS
supports
and separates muscles
Each muscle is wrapped in a thin, fibrous membrane of connective tissue called what?
fascia
What do tendons connect?
muscle to bone
What system do tendons belong to?
muscular system
What do ligaments connect?
bone to bone
What are the three layers of connective tissue?
epimysium
perimysium
endomysium
What layer of connective tissue is made of fibrous connective tissue, is composed of a layer of collagen fibers, surrounds entire muscle, separates muscle from surrounding tissues/organs, and extends into muscle attachments?
epimysium
What system do ligaments belong to?
skeletal system