Flashcards in Introduction to the musclo-skeletal system Deck (87):
What are the functions of the skeleton?
shape, support, protection, muscle attachment, provide levers, calcium regulation, blood cell production in bone marrow
What are the three types of levers?
1st class, 2nd class, 3rd class
What is a 1st class lever?
pivot in the middle
What is a 2nd class lever?
pivot at the resistance end
What is a 3rd class lever?
pivot at the effort end
What are the types of bone?
cortical/compact bone, cancellous/spongey/trabecular bone
Structure of cortical/compact bone
dense, mineral, external surface of the bone, 80% bone mass
Structure of cancellous/spongey/trabecular bone
spaceous, strong, makes up most of the bone volume, has a matrix, allows us to move effectively and efficiently, contains bone mass, 20% bone mass
General bone structure
diaphaqysis and 2 epiphyses
What are the two categories of the skeleton
axial skeleton, appendicular skeleton
What does the axial skeleton consist of?
skull, vertebrae, sternum, ribs
What does the appendicular skeleton consist of?
shoulder girdle, arm, hand, leg, foot
What types of bones are involved in the appendicular skeleton?
short bones, flat bones, irregular bones, long bones
What are the properties of the muscloskeletal system?
stiffness, strain, anisotropic
What are the two types of stiffness?
compressive (ability to resist compression), tensile (being pulled apart - bone stretches)
What is anisotropic?
a matrix made up of cologne to give it flexibility
What is bone made up of?
organic (35%) and inorganic (65%) components
What are the organic components of the bone?
cells (osteoblasts, osteocytes, osteoclasts, lining cells), matrix (1 type of collagen)
What are the inorganic components of the bone?
mineral content (hydroxyapite), hydroxyapatite (complex salt of calcium and phosphate)
What are the two types of bone growth and development?
What is longitundinal growth in a bone?
grows at the epiphyses or epiphyseal plates
What is circumferential growth in a bone ?
diameter increases throughout lifespan
What is the bones response to stress?`
What is wolf's law?
bone strength increases and decreases as the functional forces on the bone increase and decrease
How are bones modelled and re-modelled?
osteoblasts (lay down new bone), osteoclasts (breakdown bits of bone to get calcium), osteocytes
What is bone hypertrophy?
when there is an increase in bone mass due to osteoblast in response to physical activity
What is bone atrophy?
a decrease in bone mass due to ostoclasts, decrease in calcium, mass and strength
What are the functions of joints?
facilitate movement, transmit force from one bone to another
What are the synovial or diarthodial joints categorized by?
the number of axis
no axial = no axes
uni axial = 1 axis, 1 degree of freedom
bi axial = two axes, 2 degrees of freedom
tri axial = three axes, 3 degrees of freedom
What is an example of a synovial joint and what is it made up of?
e.g. the knee
- articular cartilage, articular capsule, synovial fluid
What does the articular cartilage do?
it provides a protective layer to the surface of the bone, allows movement without wear, reduces the amount of stress between joints
How thick is the articular cartilage?
What is joint stability?
the ability of a joint to resist abnormal displacement
What is joint stability provided by?
the shape of articulating bone surfaces, arrangement of ligament and muscles, other connective tissues
What are the functions of muscles?
production of movement, maintain posture, stability of the joint
What are the behavioral properties of muscle tissue?
extensibility, elasticity, ability to develop force
What are the behavioral properties common to all the muscles?
cardiac, smooth and skeletal muscle
What does the muscle tendon unit consist of?
muscle and tendon
What is the purpose of a tendon?
attaches muscle to bone
Is the muscle passive or active?
Is the tendon passive or active?
What is tendinous tissue and what is it otherwise known as?
- runs through the muscle
- otherwise called aponeurosis
What are the types of muscle action?
concentric, isometric, eccentric
What is concentric muscle action?
generation of force with shortening of the muscle length
What is isometric muscle action?
generation of force with no change in length of the muscle
What is eccentric muscle action?
generation of force with lengthening of the muscle
How are rules assumed by muscles?
through agonist and antagonist pairs, they work together to produce flexion and extension
How are agonist and antagonist pairs positioned?
opposite side of the joints
What is the stabilizer?
it stabilizers the joint
What is the neutralizer?
it neutralizes unwanted movement
What is a lever?
a relatively rigid object that may be made to rotate about an axis by the application of force
What is stiffness?
the ratio of stress to strain in a loaded material
What is compressive strength?
ability to resist pressing or squeezing force
What is tensile strength?
ability to resist pulling or stretching force
What is trabecular bone?
less compact mineralized connective tissue with high porosity that is found in the ends of long bones and in the vertebrae
What is strain?
the amount of deformation divided by the original length of the structure or by the original angular orientation of the structure
What is anisotropic?
exhibiting different mechanical properties in response to loads from different locations
What is cortical bone?
compact mineralized connective tissue with low porosity that is found in the shafts of long bones
What is trabecular bone?
less compact mineralized connective tissue, largely collagen, with high porosity that is found in the ends of long bones in the vertebrae
What is axial skeleton?
the skull, vertebrae, sternum and ribs
What is appendicular skeleton?
bones composing the body appendages
What is short bones?
small, cubical skeletal structures, including the carpals and tarsals
What is flat bones?
skeletal structures that are largely flat in shape
What is irregular bones?
skeletal structures of irregular shape .e.g. the sacrum
What is long bones?
skeletal structures consisting on a long shaft with bulbous ends .e.g. the femur
What is articular surface?
the point at which the ends of bones meet - a joint
What is condyle?
a rounded, convex protuberance at the end of a bone .e.g. femur
What is trochlea?
a pulley-like structure
What is trochanter?
a boney protrusion for muscle attachment
What is process?
a projection from a bone
What is spine?
a prominent plate
What is fossa?
a hollow or depression in a bone
What is tuberosity?
a rounded prominence, usually providing attachment for tendons or ligaments
What is a synarthroses?
a fibrous joint that can absorb shock while permitting little or no movement of the articulating bones
What are sutures?
irregularly grooved bone sheets are closely connected by fibers that are continuous with the periosteum
What are syndesmoses?
joints where dense fibrous tissues binds the bones together, permitting extremely limited movement
What are amphiarthroses?
cartilaginous joints that attenuate forces and permit more motion of adjacent bones
What are synchondroses?
joints where articulating bones are held together by thin layer of hyaline cartilage
What are symphyses?
joint where thin layer of hyaline cartilage separates a disc of fibrocartilage from the bones
What are diathroses?
joints in which the articulating bone surfaces are covered with articular capsule, which secretes synovial fluid
What are the six types of freely movable joints?
gliding, hinge, pivot, condyloid, saddle, ball and socket
What is a gliding joint?
joints where articulating bone surfaces are nearly flat and movement is permitted is non-axial gliding
What is a hinge joint?
one articulating bone surface is convex and the other is concave
What is a pivot joint?
joints where rotation is permitted around on axis
What is a condyloid joint?
joints where one articulating bone surface is an ovular convex shape and the other is reciprocally shaped concave surface
What is a saddle joint?
joint where articulating bone surfaces are both shaped like the seat of a riding saddle