Musculoskeletal Dysfunction Flashcards
What are the 5 different systems?
skeletal muscular tendon/ ligament joints fascia
What is a fracture?
traumatic- eg; hit by a car or jump
pathological- weakness over time leads to fracture
What are the two fracture types?
corticol- break all the way through
greensticks- breaks halfway through
What types of fracture occur?
Chip Slab Compound Hairline fracture Stress fracture Depression fracture
What is remodelling?
- not necessarily dysfunctional
- usually occurs due to injury or in response to forces
; Wolff’s Law: response of bone to stimuli - Commonly found in the metacarpals and metatarsals of race horses but occurs across disciplines and across species
What is osteopaenia?
generalised demineralisation, disuse
What is osteoitis?
inflammation of the bone
What is osteoporosis?
degeneration- not yet proved in animals but no studies yet performed
What species are bone tumours and cysts more common in?
dogs
What is hypertrophy and atrophy?
changes in muscle volume due to increase or decrease in size of individual muscle cells
potentially reversible
caused by
What are the three types of Atrophy?
Generalised
- Poor nutrition/malnutrition
- Severe systemic illness – nutritional resource
- Usually occurs symmetrically
Localised
- Paralysis
- Immobilisation (disuse)
- Rhabdomyolysis (rapid breakdown of muscle tissue
Neurogenic
- Localised (PNS)
- CNS damage
- CNS infection
What is trauma?
wounds
strain
tear
What are wounds?
lacerations
burns
puncture wounds
abrasions
What is stain?
commonly used when less fibres are involved and the trauma is localised
What is tear?
visible tearing of muscle
eg; muscle bellies or attachments
How does the body heal after trauma?
Compartmental Myopathy
Lameness occurring following inflammation and restricted swelling
Common in caudolateral antibrachial
Surgical intervention - Fasciotomy
Fibrosis
Scar tissue mineralises
Forms hard portions of muscle that have no stretch ability
Common on the hind limbs of both dogs and horses
- Turning
- Sliding stops
- Trapped limbs
- Abscess at injection sites
What is fibrotic myopathy?
Mainly semitendinosus, occasionally semimembranosis or gracilis
Abnormal gait
Most obvious at walk
Palpable thickening on caudal upper hind limb
Often associated dimple in muscle belly
Also traumatic/degenerative neuropathy
What is rhabdomyolysis?
Tyeing up
Condition of enzymic reaction causing breakdown of muscle tissues
Symptoms range from mild stiffness to full muscle cramps affecting regions of the whole body
-Myoglobinuria can be secondary
Often starts 15-30 minutes into an exercise session
Sporadic or recurring
Serum enzyme levels increase
- Aspartate animotransferase (AST) – slower
- Creatine Kinase – quicker
Affects both horses and dogs, mostly effects athletic and competition animals
What is polysaccharide storage myopathy? PSSM
Horses only
Accumulation of glycogen and abnormal polysaccharide
- Altered intracellular glucose homeostasis
- Insufficient ATP production
- Rhabdomyolysis
more common in draft breeds
Histopathology
Abnormal accumulation of amylase resistant PAS positive polysaccharide inclusions (often not apparent until > 15months old)
What are the clinical signs of PSSM?
stiffness
lethargy
exercise intolerance
muscle contractions
What does PSSM cause?
Generalised reduced muscle mass
Muscle atrophy
HL weakness
Reluctance to back
How is PSSM prevented?
Prevention
Daily regular exercise
Free exercise in pasture
High fat (13%) low starch (<10%) content of daily digestible energy
What is atypical myopathy?
Horses only
Frequently fatal (75-90% mortality)
Rapid treatment essential
Seasonal – grazing horses
Sycamore tree seeds
-Hypoglycin – A
Rapid onset non-exertional rhabdomyolysis
