Topic 2: Introduction to Myology and Arthrology Flashcards
define the term joint
A joint is a union between two or more parts of the skeleton (bone and bone, bone cartilage etc)
fibrous joint
Fibrous tissue (dense irregular connective tissue) uniting the bones
Amount of movement possible depends on the lengths of the fibres
Sub-types:
- Suture: immovable (skull)
- Syndesmosis: slightly moveable (radioulnar joint)
- Gomphosis: immovable (teeth)
cartilaginous joints
Cartilage uniting bones
Amount of movement possible depends on type of cartilage
Sub-types:
- Primary cartilaginous (synchondrosis): immoveable (epiphyseal plate)
- Secondary (symphysis): slightly moveable (intervertebral discs, pubic symphysis)
synovial joints
Joint cavity in between the bones, containing synovial fluid
All are freely moveable
hinge joints
Uniaxial
Flexion and extension
Elbow
pivot
Uniaxial
Rotational
atlantoaxial joint
ellipsoid/condyloid joint
Biaxial
flexion, extension, adduction, abduction, and circumduction.
Wrist (radiocarpal) joint
saddle
Biaxial
Flexion, extension, abduction, adduction and circumduction
1st carpometacarpal joint
ball and socket
Multiaxial
Flexion, extension, abduction, adduction, circumduction, medial (internal) and lateral (external) rotation.
plane joint
Multiaxial
Gliding movements
Intertarsal joints
structure and function of ligaments
bands of fibrous tissue that occurs at joints
Acts as mechanical constraints (prevent unwanted movement, limits allowed movements)
sensory - proprioception
structure and function of articular discs
Pads of fibrocartilage that are situated between the articular surfaces of some synovial joints
Functions:
- Act as shock absorbers
- increase stability
- Assist with lubrication
- Permit different movements to occur simultaneously at the same time
structure and function of bursae
Synovial fluid-filled sacs are many synovial joints
Function: to reduce friction
- Located between layers of muscles and between muscles/tendons and bones
medial vs lateral rotation
medial = towards midline
lateral = away from midline
inversion vs eversion
inversion = turning sole of foot inwards
eversion = turning sole of the foot outwards
parts of a skeletal muscle
muscle belly: contractile portion
attachment sites: tendons attaching the muscle to the bone
parallel skeletal muscle
fascicles arrange parallel to the long axis of the muscle
strap skeletal muscle
Narrow and strap-like
e.g. Sartorius
fusiform skeletal muscle
Spindle-shaped
e.g. Biceps brachii
flat (quadrilateral) skeletal muscle
Short and flat
e.g. Quadratus femoris
oblique
Fascicles arranged obliquely to the tendon that runs the entire length of the muscle
unipennate
Fascicles attach to one side of the tendon (extensor digitorum)
bipennate
fascicles attach to both sides of the tendon (rectus femoris)
multipennate
multiple bipennate arrangements attaching to one common tendon (deltoid)
circular
fascicles arranged concentrically around an opening
structure and function of tendon sheaths
thin layer of connective tissue
function: aid in smooth movement of tendon tissue and prevent deviation during muscle contraction
isometric muscle contraction
Tension developed, but no change in muscle length
No change in length = no movement produced
Example: holding a dumbbell still/holding a plank
isotonic muscle contraction
Tension developed with change in muscle length
Change in length = movement produced
eccentric: muscle lengthens e.g. lowering dumbbell
concentric: muscle shorten e.g. lifting dumbbell
agonist muscle
muscle producing desired movement
fixator (stabiliser)
muscle which stabilises a body segment so that the agonist can produce the desired movement e.g. back muscles when lifting
antagonist
muscle which must relax to allow desired movement to occur
synergis
muscle which contracts to cancel out unwanted action of the agonist e.g. forearm pronator during elbow flexion
