Muscle pathology Flashcards

Question

Describe treatment of white muscle disease

Answer 1

Prognosis for cardiac form is poor Selenium (parenteral) +/- vitamin E (oral) Prevention of decubital ulcers Attention to food / water intake Antibiotics if secondary infection E.g. pneumonia, infected ulcers

Answer 2

Most common in horses Prolonged GA in recumbency Pressure on the muscles leads to hypoperfusion / ischaemia Localised or generalised

Answer 3

Occur within 30-60mins of standing Muscle can be flaccid or hard Hot and painful on palpation Weakness Restlessness, anxiety etc. Lateral recumbency  triceps, deltoid, hindlimb extensors Dorsal recumbency  longissimus dorsi, gluteal muscles

Answer 4

Anti-inflammatories Sedatives IVFT +/- slings for support +/- glucocorticoids

Answer 5

Atypical myoglobinuria’ Young horses kept at pasture Ingestion of sycamore seeds – hypoglycin A (HGA) Acute rhabdomyolysis postural, respiratory and cardiac muscles

Answer 6

General weakness Difficulty in walking and standing Dyspnoea (difficulty in breathing) Muscle tremors Lethargy Colic signs (but with an appetite) Brown / dark red urine

Answer 7

Hypoglycin A can be detected in a blood test Can test seeds, plants etc for the toxin Treatment Supportive care Fatal in up to ¾ of horses.

Answer 8

Rhabdomyolysis – necrosis of the muscle Associated with exercise, excitement or stress Also known as: Tying up Azoturia Monday morning disease

Answer 9

Regardless of causes, all tend to present in a similar way Most commonly seen during or after exercise, following a period of rest: Stiff, stilted gait Excessive sweating High respiratory rate Painful, firm muscles Myoglobinuria

Answer 10

Can occur due to: Overexertion - Exercise above the level of the horses training Electrolyte imbalance - Na+ / K+ / Ca+ / Mg+ all involved in muscle contraction Vit E / Selenium deficiency - Damage from free radicals Diet - High-grain diet

Answer 11

Clinical signs Muscle enzymes CK - creatinine kinase LDH – lactate dehydrogenase AST – aspartate aminotransferase Muscle biopsy

Answer 12

Anti-inflammatories Rehydration – IVFT Sedation if required Box rest with hand walking Gradual return to work

Answer 13

Horses have repeated episodes of ER Due to abnormal intracellular calcium regulation Two inherited conditions: Polysaccharide storage myopathy Recurrent exertional rhabdomyolysis

Answer 14

Quarter horses, Draught horses and Warmblood breeds Inherited enzyme defect Results in abnormal storage and utilisation of glycogen 1.5 – 4 x normal glycogen levels in muscle When exercised, cannot generate adequate energy Reduction in glycolysis  ATP Dysfunction of membrane pumps Increased intracellular Ca+

Answer 15

Diagnosis is made from muscle biopsy No cure so long-term management needed Exercise regime Consistent turn out and gradual increase in training Do not stable > 48hrs Dietary modification Reduce dietary glucose Use fat as a means of energy

Answer 16

Racing Thoroughbreds, Standardbreds and Arabs Females Nervous horses Defect in regulation of muscle contraction Expressed when subjected to stress/exercise Clinical signs the same but occur once the animal becomes fit Stress or excitement at the time of exercise

Answer 17

1. Address exercise regime Daily turnout essential Gradual return to exercise Long warm up / cool down sessions 2. Minimise stress 3. Dietary management Low starch High fat Vit E / selenium

Answer 18

Dantrolene Reduces calcium release during contraction Reduces intracellular Ca+ Give 1hr prior to exercise Phenytoin Acts on ion channels Must be withdrawn 7 days prior to racing

Answer 19

Pure and x-breed quarter horses Hereditary Stallion ‘Impressive’ Sired >102,000 registered QH Males > females < 4 years (2m-15y)

Answer 20

Muscle stiffness Sweating Muscle fasciculations Muscle weakness Tremors Collapse

Answer 21

Exercise in hand/by lunging Adrenalin helps replace intracellular K+ Feeding grain Acts as supply of carbohydrates  glucose Glucose stimulates insulin  encourages K+ uptake Diuretics Acetazolamide Increase K+ excretion

Answer 22

Dietary modification – low potassium (avoid alfalfa, molasses) Regular exercise Diuretics can be used long term if required Affected horses should NOT be bred from

Answer 23

Similar to ER in horses Greyhounds, sled dogs etc Predisposing factors: Inadequate fitness for level of work Excitable / tense animal Hot, humid weather Excessive bouts of extreme exertion

Answer 24

Usually occur within 2-5 days of exercise Muscle swelling and pain ++ Tremendous thirst Acute form: Generalised stiffness Dragging of pelvic limbs Distress Tachypnoea (increased respiratory rate)

Answer 25

Reduce body temperature – cold packs etc Intravenous fluid therapy – hydration and electrolyte imbalance Dantrolene Pain relief Muscle relaxants – diazepam Mild forms – warming of muscles, short lead walks, comfortable bedding

Answer 26

Neuromuscular disorder Dysfunction of the post-synaptic membrane of the neuromuscular junction Congenital Inherited deficiency in acetylcholine receptor Acquired Autoimmune Antibodies bind to the acetylcholine receptors

Answer 27

Focal 40% of affected dogs and 14% of affected cats Megaoesophagus (regurgitation) No detectable weakness in rest of body Generalised Muscle weakness that worsens with exercise

Answer 28

Anticholinesterase therapy Reduces destruction of acetylcholine +/- Immunosuppressive doses of glucocorticoids If megaoesophagus present Modify feeding Feed from a height Upright position for 10-15 mins post-feeding

Answer 29

Swimmer puppy syndrome / Turtle-pup Chondrodystrophic breeds and small terriers and cats! Myofibril hypoplasia Inability to walk by 3 weeks of age Splayed hindlimbs +/- forelimbs

Answer 30

Unknown aetiology. Possible links to: Environment Slippery floors where the newborns are housed in the first few weeks of life Weight Weight gain that exceeds the skeletal growth Neuromuscular disease Dysfunction, or delay in development, of the neuromuscular system

Answer 31

By 3 weeks of age: Inability to stand or walk Splayed hindlimbs +/- forelimbs ‘Paddling’ motion Regurgitation Sores on ventrum Pectus excavatum - dorsoventral flattening of the chest

Answer 32

Environment Non-slip, soft flooring Physiotherapy Passive ROM Massage ? Hobbles Feeding regime Feed from a height Keep upright for 15mins after feeding Nursing care Cleaning of ventrum Nutrition

Muscle pathology Flashcards

(56 cards)