what cell type makes up cartilage?
chondrocytes
what materials make up cartilage?
chondrocytes, collagen (& other organic matrix components) & water
most common joint
synovial joint
label this
synovial membrane
surrounds joint space of synovial joint secretes synovial fluid
fibrous joint capsule
strengthens synovial joint
a healthy shoulder in arthroscopy should be:
smooth & white
what can a diseased shoulder joint look like in an arthroscopy?
rough & bumpy with detached tissue, synovial fluid becoming discoloured
what is the function of articular (hyaline) cartilage?
providing smooth gliding surface (lubrication) shock absorption (stiff to compression) distributes load & protects underlying bone
articular cartilage: what is the vasculature like? what does this mean for healing properties?
no vasculature/nerve supply limited capacity for healing/repair
spot the chondrocytes
dark pink dots within white spaces = chondrocytes
synovial fluid
clear/straw coloured contains hyaluronic acid provides lubrication, shock absorption & nutrient/waste transport
menisci
accessory joint structure for shock absorption (not every joint has this) c-shaped piece of tough, rubbery cartilage
bursae
fluid filled sack, cushioning tendon as it pushes against sesamoid bone
tendon sheath
like bursae but wrap around tendon where they pass over joints
synsarcosis joint
only muscular attachment (e.g. scapula onto ribcage)
fibrous joint
least mobile joint, connecting neighbouring bones w little to no movement (e.g. flat bones within skull)
cartilaginous joints
some motion, but not too much (e.g. pelvis allowing child to pass through canal, intervertebral disks)
multi-axial joint example
ball & socket
bi-axial joint example
condyloid saddle
uni-axial joint example
pivot hinge
gliding joint example
planar
pivot joint
peg fitted within ring, peg rotates around ring (or vice versa)
hinge joint
one articular surface convex, other is concave, usually a 'notch' is present to limit motion
condylar joint
convex surface w corresponding concave cavity
saddle joint
two surfaces - convex in one direction, concave in the other at right angles
joint motion
when two or more bones meet to allow movement
what does a greater range of movement increase? why?
greater the range of movement = higher the risk of injury strength of the joint is reduced
moment arm
length between joint axis and the line of force acting on the joint