Movement Flashcards
What are the three types of muscle?
Cardiac muscle
Smooth muscle
Skeletal muscle
Describe the structure of skeletal muscle
Skeletal muscle is made from fascicles
Which are made from muscle fibres
Which are made from myofibrils
Which are made from actin and myosin microfilaments
What happens when a muscle is strained?
Some muscle fibres are torn
Is skeletal muscle striated?
Yes
What increases with increased muscle fibre length?
Potential shortening range
Potential range of movement at joint
Name the different types of skeletal muscle and where they can be found
Circular - surrounding eye Fusiform (spindle) - biceps brachial Pennate (like a feather) - deltoid Quadrate - rectus abdominus (abs) Flat with aponeurosis -external oblique
What must a skeletal muscle do in order to move a joint?
Cross joint i.e. Be attached to bones on both sides
What is the only thing a skeletal muscle can do to the origin and insertion?
Bring them closer together
In how many places must a skeletal muscle be attached to bones?
At least 2
To what do facial muscles insert?
The skin
When referring to skeletal muscles, what is the origin?
Attachment point
usually proximal
usually remains still during movement
When referring to skeletal muscles, what is the insertion?
Attachment point on other side of joint
Usually moves
Usually distal
Can tendons contract?
No - noncontractile
What attaches muscle to bone?
Tendons
What is an aponeurosis?
A flattened tendon
Often associated with flat muscles
Attach muscle to soft tissue
What features of a muscle can be described in the name?
Shape Location Relative size (major, minor, longis, brevus) Main bony attachment Main movement
What determines possible movements in joint?
Shape or articular surface
How can you carry out a clinical exam on a skeletal muscle?
Ask patient to move in certain ways
Test reflex
What is examined in a clinical examination of a skeletal muscle?
Power and mobility
Nerve supply
What is a reflex?
Rapid, involuntary reaction to danger
What are the two main reflexes involving skeletal muscles?
Stretch
Flexion withdrawal
When does the stretch reflex occur?
When tendon is stretched, prevents muscle being overstretched
When does a flexion withdrawal reflex occur?
Touch something dangerous - fire
Give some examples of stretch reflexes
Knee jerk
Ankle jerk
Triceps jerk
Biceps jerk
What happens during a deep tendon reflex?
Muscular sensory nerve detects stretch and relays info to spinal cord
Signal passed to motor nerve
Motor nerve stimulates contraction
What is the neuromuscular junction?
Junction between motor nerve and muscle
What is the reflex arc?
Route taken by signals during reflex
What does a normal stretch reflex indicate?
Muscle, sensory and motor nerves, spinal cord connection, neuromuscular junction, and descending controls from brain are working
What is muscle paralysis?
No functioning motor nerve supply
Describe a paralysed muscle?
Decreased muscle tone
Cannot contract
What is muscle spasticity?
Muscle has working motor nerve but descending controls from brain not working
Increased muscle tone shown
What occurs during muscular atrophy?
Myocytes reduce in size
What causes muscular atrophy?
Inactivity
Bed bound, cast, damage to motor nerve
What is the opposite of atrophy?
Hypertrophy
Individual myocytes increase in size
What is hyperplasia?
When the myocyte size remains the same but more cells are formed
Describe location and covering of skeletal muscles
Deep to deep fascia
Covered by fibrous connective tissue
What are the fascia and muscle compartments separated by?
Deep fascia and intermuscular septum
Name the compartments in the thigh
Anterior
Medical
Posterior
Name the compartments in the leg
Anterior
Posterior
Lateral
Name the compartments in the arm
Anterior
Posterior
Name the compartments in the forearm
Anterior
Posterior
What is a fasciotomy?
An emergency procedure to relieve pressure in limb
What can happen when there is swelling or bleeding in a compartment?
No where else to go - pressure increases
Can disrupt nerve and muscle function
What kind of muscle is the diaphragm made of?
Skeletal
What do skeletal muscles control in proximal alimentary/respiratory tract?
Coughing, sneezing, gagging, swallowing, vomiting,
