Muscle Injuries Flashcards
What are the passive elements of muscle?
- Tendon
- Musculotendinous junction
- Connective tissue in 3 layers
What are the active elements of muscle?
- Muscle fibres of myofibrils
- Neuromuscular components
- Efferent & afferent systems
What are the layer of connective tissue around muscle cells/fascicles/bundles?
- Perimysium
- Epimysium
- Endomysium
What are the different energy systems that drive muscle contractions?
- Glycolysis: anaerobic, stored energy
- Oxidative system - aerobic, slower process, endurance (Kreb’s)
What are the different types of muscle fibres?
- Type I: Slow twitch, aerobic
- Type IIA: Intermediate, anaerobic & aerobic
- Type IIB: Fast twitch, anaerobic
What is the function of muscle spindles?
- Pre-set tension of muscles
- Constantly adjusting according to length of muscle during rest & required tension
- Influenced by stretch, contraction, joint mechanoreceptors, inflammatory mediators, SNS, pain, temperature
- Important for ROM, control, reaction time
What is the function of golgi tendon organs?
- Ensures muscle is not overloaded, overstretched & doesn’t contract too strongly
- Overrides muscle spindle system
What do strength adaptations depend on?
Increased use
- Recruitment (function of neural drive)
- Cross sectional area (hypertrophy)
What factors modulate strength adaptation?
- Pain adaptation
- Neural adaptation
- Specificity
- Age
What does immobilisation result in?
Atrophy & length changes due to
- Contractile elements
- Connective tissue elements
What are the different types of muscle injury?
- DOMS
- Contusion
- MTJ
- Belly
- Tendon
- Complications (compartment syndrome, myositis ossificans)
What are the different types of muscle contusion?
- Intra-muscular: Haematoma associated with muscle strain/bruise
- Inter-muscular: Muscle fascia ruptured, blood spreads to interfascial & interstitial spaces (emergency)
What are the different grades of muscle strains?
- Grade 1: Minimal structure damage & haemorrhage, 2-3 weeks recovery
- Grade 2: Partial tear, significant early functional loss, 3-6 weeks recovery
- Grade 3: Complete tear, may require surgery, 3+ months recovery
What are the phases of healing for muscle sprains?
- Destruction: Haematoma & oedema, necrosis of muscle tissue
- Repair: Haematoma invaded by phagocytes, connective tissue scar & capillary ingrowth, muscle regeneration
- Remodelling: Maturation & contraction of muscle, re-organisation of scar tissue
What is myositis ossificans?
- Non neoplastic proliferation of bone & cartilage (calcification mass)
- At site of previous trauma, repetitive injury or haematoma in muscle
- Suspect if pain remains 14-21 days post injury
- RICE, gentle ROM/stretching, surgery may be required
