Joints, Movement & Biomechanics Flashcards
what is a peridontal ligament?
thin fibrous tissue connecting bone of socket to root of tooth
what determines what bone moves the most in a muscle contraction?
where the muscles are attached on each bone
ex: radius moves more than scapula when doing bicep curl
what are symphysis cartilaginous joints, the functional classification and example?
- hyaline cartilage covers the articulating surface and is fused to an intervening pad of fibrocartilage
- amphiathrotic joint (strength/ flexibility)
- ex: pubis symphysis/ cartilage disk between vertebrae
what is the point of origin?
the bone that doesn’t move as much on the site of attachment
ex: scapula in bicep extension
what is FLE 123?
1st class- fulcrum in middle
2nd class- load in middle
3rd class- effort in middle
what forms the fulcrum, lever, effort, and load in the body?
Lever- Bones
Fulcrum- Joints
Effort- Muscles
Force - weight of body/the object we lift
what are the 3 subcategories for fibrous structual joints?
1) suture
2) syndesmosis
3) gomphosis
what are fibrous structural joints?
dense fibrous connective tissue
what is the effort arm?
the distance from the point of effort to the fulcrum
what is the movement of a ellipsoidal joint and example?
comprise of concave and convex articulating surfaces
(ends of bones are oval, but still convex/concave)
- angular and circumduction movement
ex: metacarpals/carpals
what is primarily involved with biomechanics?
skeletal mucles
- the muscle has to be attached to the bone in some way in order to function the muscle
- muscles attached to bone by tendons
what is the effort/force?
the applied movement to move lever
what are cartilagnious structural joints?
cartilage between bones
what is muscle contraction?
the muscle becoming shorter
- all end points of a muscle needs to be attached
- each end needs to be attached to at least 2 different bones accross a joint
ex: bicep needs to attach to scapula and radius to contract
the movement of the point of insertion towards the point of origin of the muscle
what is structural classification?
look at the anatomical organization and see what is the material that make up the joint
what is the synchondrosis cartilage joint, functional classification and example?
- A bar plate of hyaline cartilage that unites the bones
- all synchondrosis are synarthrotic
- ex: ribs attached to sternum
what is an example of a first class lever system in our body?
Head nodding
Fulcrum- vertebral column
Effort- neck muscles in back contracting
Load- head tilting back
what are ligaments?
bands of fibre that hold articulating bones together to provide stability
what are the 3 structural joints?
1) firbrous
2) cartilaginous
3) synovial
what is a first class lever?
fulcrum is between load and effort
power or speed lever
what are factors that stabilizes synovial joints?
- collagen fibres
- articulating surfaces and menisci
- other bones, muscles, or fat pads
- tendons of articulating bones
prevent injury by limiting range of motion
what determines whether the specific lever is a power or speed lever?
the specific point of insertion of a muscle
what are the 2 membranes of the articular capsule?
1) fibrous capsule
2) synovial membrane
what is an example of a third class lever in our body?
Bicep curl
Fulcrum: elbow
Load: weight carried in hand
Effort: bicep contract
what is second class lever?
resistance is between fulcrum and effort
Power lever
what makes up a typical synovial joint in the knee?
- periosteum
- ligament
- joint cavity
- articular capsule (double membrane)
- synovial fluid
what are gomphosis joints functional classification and example?
- synarthrotic joints
- ex: between teeth and peridontal ligament
what is the movement of a pivot joint and example?
ring shaped articulating surfaces
- rotational movement only
ex: atlas around dens of axis
what is abduction vs adduction?
Abduction:
moving away from midline
Adduction:
movign towards the midline
fibrous joints facts
- articulating bones held closely together by dense irregular connective tissue
- permit little/ no movement
- found in skull
what is the movement of a hinge joint and example?
concave and convex articulating surfaces
- one bone remains stationary while the other moves around
- movement is angular, one plane of motion
ex: elbow / knee
what are the 6 types of synovial joints?
1) gliding
2) hinge
3) pivot
4) ellipsoidal
5) saddle
6) ball & socket
what are biomechanics?
how bone and muscles affect movement
what is the point of insertion?
the bones that moves the most with the site of muscle attachment
ex: radius in bicep curl
what is the movement of saddle joints and example?
articulating surfaces are “saddle” shaped
- allows for angular and circumduction movements
ex: base of thumb
what is the functional classification and example of where to find syndesmoses joints?
- synarthortic or amphiarthrotic joints
- bones connected by fibrous tissue ligament
- ex: between fibula and tibia
what is the synarthrotic joint classification?
not moveable
“sin not to move”
what is the load?
the amount placed on the lever
what are the 2 types of cartilaginous joints?
1) synchondroses
2) symphyses
what are bursae (bursa)
pockets of synovial fluid that cushion areas where tendons and ligaments rub together
- reduce friction at joints
- synovial membrane makes up burse
what is the functional classification for synovial joints and example?
- Diathrotic joint
- ex: knee joint
what are the 4 major types of movement at synovial joints?
1) gliding
2) angular
3) rotation
4) circumduction
what is the glising movement?
movement of 1 bone over another
- allows side-to-side and bacl/forth action
ex: between carpals/tarsals
what can muscle only do?
contract
can not relax on their own
needs to be stretched again in order to contract again
what do levers consist of?
1) fulcrum
2) load
3) effort/force
what is determines based on where your muscle is located?
the amount of effort required to move
what is the ligament connecting the fibula and tibia together?
tibiofibular ligament
- shorrter the ligament, shorter the movement
what is an example of a second class lever in our body?
Calf raise
Fulcrum- ball of foot
Load- Body weight
Effort- Calf muscles
what is the load arm?
the distance from the fulcrum to the load
what is functional classification?
how much range of motion a joint is capable of
what is the diathrotic joint classification?
freely moveable
“dhiarreha”
whata are the 3 joint classifications based on the functional classification?
1) synarthrotic
2) amphiarthrotic
3) diathrotic
what is the functional classification and location for sutures?
- synarthrotic joint (adults)
- amphiarthrotic joint (infants)
ex: skull
how do muscles work antagonistically?
they work against each other
ex: bicep contracts, needs tricep to contract to stretch out bicep again
what are the 2 suncategories for cartilagnious structual joints?
1) synchondrosis
2) symphysis
what happens when theres a longer effort arm?
easier to lift the load
what is the difference of a power vs speed lever?
power lever: can move heavier
speed lever: can move distance
what happens when the insertion is further away from fulcrum?
more power the lever
what are the 6 subcategories for synovial structural joints?
1) gliding
2) hinge
3) pivot
4) ellipsoidal
5) saddle
6) ball & socket
what is the difference of agonist and antagonist?
agonist: the muscle contracting
antagonist- the muscle relaxing
ex: when bicep contacts (agonist), tricep relaxes (antagonist)
what is rotation?
bone rotates around its long axis
- turning motion
- ex: head shaking no
what is flexion vs extension?
Flexion:
decrease in angle (less than 90)
Extension:
Inclease in angle (more than 90)
ex: elbow joint
what is the formula to determine amountof force exerted by biceps to maintain forearm in equilibrium when hand is holding certain weight?
length of effort arm x effort = length of load arm x load
1) write out equation
2) move length of effort arm over
3) divide total of length of load arm x load by the length of effort arm
what are angular movements in synovial joints?
angle in articulating bones increases or decreases
- swinging from side to side or up and down
- abduction and adduction
what is a fulcrum?
the fixed point of a lever
what are articulating bones?
2 bones joined at a joint
what are levers?
allowing a given effort to move a heavier load or move a load farther and faster
rigid bar that moves on a fulcrum
what happens when insertion is closer to fulcrum?
lever is less powerful
BUT gets greater range of movement and speed of movement of that lever
what are menisci (meniscus)?
pads of cartilage that allow bones of different shapes to fit together more tightly.
- acts as a spacer in a joint and prevents bones smashing together
what is circumdiction?
movement of a body part in a circle
- one end stable, distal end moves in circle
what is the movement of ball & socket joints and example?
rounded head of 1 bone in a depression of another
- angluar, rotational and circumduction movements
ex: shoulder and hip
what are the 2 methods of joint classification?
1) functional classification
2) structural classification
what is a third class lever?
effort is between fulcrum and load
speed lever (most common in our body)
what is the amphiarthrotic joint classification?
slightly movable
“amphibian”
what is synovial fluid?
fluid secreted by synovial membrane that lubricates joints, absorbs shock, and supplies oxygen/nutrients to cartilage
whar are synovial structural joints?
cavity between articulating bones, ligaments hold bones together
