Lecture 3: Intro to Musculoskeleteal System Flashcards
Axial Skeleton?
Trunk, skull, neck
Appendicular Skeleton
Limbs, pelvic girdle, pectoral girdle
long bones in arms and legs
humerus, radius, ulna, tibia, femur, fibula
hand and feet bones
metacarpals, carpal bones, phalanges; metatarsals, tarsal bones, phalanges
different types of bony features
functional, adjacent structure applies a force, adjacent structure develops at the same time
what are skeletons made up of?
bones and cartilage
Bones are..?
hard connective tissue, not flexible, connected to skeletal muscles, provide support and protection, calcium metabolism, production of red blood cells
cartilage is…?
more flexible, normally located where movement is required (e.g. at articulations)
name 3 types of joints and which are more mobile
synovial (most flexible), cartilaginous, fibrous
what are mobility and stability in terms of joints
inversely proportional e.g. shoulder
5 facts about joints
joints have many sensory nerves
the receptors for sensory nerves detect pain, temp, touch and proprioception
joints are supplied by articular branches
periarticular arterial anastomoses are common
arteries can be damaged by dislocation
general intro to skeletal muscles?
tough fibrous connective tissue, they allow movement, are found in the deep fascia
what’re the different types of skeletal muscles
flat with aponeurosis, fusiform, quadrate, pennate, circular
what is aponeurosis
flattened tendon therefore associated with flat muscles, attach muscle to soft tissue
how to name muscles
shape, location, bony attachment, main movement, size
what are the 2 points of skeletal muscle attachment called
origin and insertion
what is contraction
when the origin and insertion move closer together by the skeletal muscle
by what axis do the muscle fibres shorten along
long axis
what is the difference between ligaments and tendons
ligaments connect muscle to muscle, tendons connect muscle to bone
where are tendons found
at either end of muscle
what is the direction of movement based upon?
which side of the joint the muscle spans
how can the action of any joint be figured out
which joint is spanned
the long axis of the muscle fibres
the shapes of the articular surfaces of the joints
aspects of the joint that is spanned?
why is the deltoid joint so special?
has 3 different origins and 1 insertion.
posterior fibres allow for extension of shoulder
middle fibres allow for abduction of shoulder
anterior fibres allow for flexion of shoulder
what are the 2 main skeletal muscle reflexes
stretch reflex and flexion withdrawal reflex
what is flexion withdrawal reflex?
sudden flexion to withdraw from danger e.g. hot hob. nerve synapses occur at spinal cord level so no brain involved
what is a stretch reflex?
a hammer is used to further stretch muscle via the tendon, in order to avoid overstretching of muscle the muscle contracts resulting in a muscle-belly twitch.
how does the stretch reflex happen at a neurone level?
sensory neurones detect the muscle being stitched, they synapse with a motor neurone at the spinal cord, motor neurones tell muscle to contract. descending controls from the brain prevent an over reaction by the muscle (e.g. kick)
what would a normal stretch reflex reaction indicate?
normal function of the; sensory neurones motor neurones muscle synapses (at spinal cord and Neuromuscular junction) descending controls from the brain
what is muscle paralysis
no functioning motor serve supply. muscle cannot contract, reduced tone
what is muscle spasticity
the descending controls from brain do not work, muscle would have increased tone
what is muscle atrophy and hypertrophy?
atrophy (muscle wasting): reduction of muscle fibre size, reduces muscle bulk. cause by inactivity (e.g. immobilisation)
hypertrophy: muscle fibres enlarge
