Muscles Flashcards
Which muscle innervates the hamstring muscles? (Semitendonous, semimembranous and biceps femoris)
The sciatic nerve. Originates from L4-S3
What is compartment syndrome?
Often occurs after a fracture. Secondary swelling in a muscle compartment with non-distensible fascial sheath. Treatment is by fasciotomy.
Describe the 3 grades of muscle strains/tears.
Grade 1- few fibres, localised pain and no loss of strength. Grade 2- significant number of fibres, swelling, pain on contraction, reduced strength and limited movement. Grade 3- complete tear- most common at musculotendinous junctions.
What is myositis ossificans?
After a muscle injury a hematoma forms and if this calcifies this is myositis ossificans. Most common in sever contusions. Most resolve spontaneously but recovery is slow.
Where do tendon injuries normally occur?
At the point of least blood supply eg. Achilles tendon at musculotendinous junction or 2cm above insertion into calcaneum.
How do you get more force?
1) More complete activation of one muscle.
2) More activation of agonist muscles.
3) More inactivation of antagonist muscles.
What is a motor unit?
A single motor neurone and all the muscle fibres it innervates.
What does strength training do?
Early changes include better motor unit activation, less antagonist activation,, improved glycolytic metabolism, after 6 weeks there is fast fatiguing fibre hypertrophy.
What does endurance training do?
Enhanced oxidative metabolic profile, more mitochondria, improved oxygen supply, more myoglobin, slow and fast fatigue resistant fibre hypertrophy.
What is fatigue?
Inability to maintain power output, reversible by rest. Fatigue is NOT due to ATP running out, if this happens muscles go into rigor, not fatigue.
What is sarcopenia?
A syndrome characterised by progressive and generalised loss of skeletal muscle mass and strength associated with ageing, with a risk of adverse outcomes such as physical disability, poor quality of life and death. In primary sarcopenia, no cause evident other than ageing. Secondary sarcopenia can be disease related, activity related or nutrition related.
What is the innervation of Rhomboid?
Dorsal scapular nerve
