Muscular Dystrophy Flashcards
Name of protein lacking with muscular dystrophy.
Dystrophin.
Provides structural, lattice like support allowing free mvt of ions n helps hold membranes together during mm contraction.
Muscular dystrophy is a disorder of the nerve that innervated the muscles.
True or false?
False.
Muscle itself is affected.
What is the name of the enzyme theorized to “leak” from the membranes due to lack of dystrophin protein?
Creative kinase.
Necessary for producing energy needed for mm contraction.
What is the most common type of dystrophy?
Duchennes.
X-linked. Inherited exclusively by boys. Seen as early as 18months.
Growers sign (falling /difficulty getting up)
What are some characteristics of Duchennes?
- waddling gait
- anterior pelvic tilt
- weakness of hip extensors and thighs
- intellectual impairment is common
- shoulder weakness
- pushes abdomen forward
Which dystrophy resembles Duchennes?
-Becker (less severe)
- pseudohypertrophy of calves
- onset usually late teens
- toe walking
- confined to wheelchair by 30
- some level of intellectual impairment
- daughters become carriers, sons affected
Which dystrophy is x-linked recessive?
-Emery (Dreifuss dystrophy)
- early childhood diagnosis
- foot drop, mm weakness primarily shoulders, upper arms, tib ant and peroneals
- pelvic girdle affected in later life
- contracture before weakness
- thoracic n cervical flex reduced m limited
Emery dystrophy has intellectual impairment, calf enlargement and pseudohypertrophy.
True or false?
False.
No intellectual impairment
No calf enlargement or pseudohypertrophy
What areas are predominantly affected with limb girdle dystrophy?
Hips and shoulders.
- weakness eventually extends to other muscles.
- respiratory function may decline with scoliosis
Which dystrophy presents with a general full life expectancy?
-fascioscapulohumeral dystrophy
What causes foot drop and altered gait with fascioscapulohumeral dystrophy?
Weakness in tibialis anterior and peroneals
-1/2 will develop pelvic weakness and require wheelchair
Which dystrophy predominates in Sweden?
Distal dystrophy.
- Normal life span, occasionally proximal mm affected
- males m females affected
- onset 20-30yrs old
- fine motor mvt of hands n fingers affected
- can’t heal or toe walk
Which dystrophy is found in French Canadian families?
Occulopharyngeal dystrophy
- affects eye mvt (incoordination) -diplopia
- drooping eye lids, mild neck weakness, dysphagia
- May be traced back to mitochondrial cell mutations
- 30yr + onset
Floppy baby syndrome is associated with which dystrophy?
-congenital dystrophy
- group of dystrophies present at birth
- myotonia present (delayed mm relaxation after contraction)-worse in cold weather
- often affects hands
- cataracts common, glandular disorders, reduced fertility -NO pseudohypertrophy
Anticipation is associated with which dystrophy?
And what does the term mean?
- congenital dystrophy
- feature of condition in which each generation exhibits increasingly severe signs n symptoms
