WEEK 2 Flashcards
what are the 6 subjects that joints consist of
1- bone
2- ligaments
3- tendons
4- cartilage
5 - joint capsules
6- muscles
define a joint
an articulation of two or more bones
describe the shoulder joint (x3)
- the subacromial bursa is a fluid filled sac in between tendon and the bone
- this bursa helps to protect soft tissue from damage
- need stability to stop joint from dislocation
what are the 2 main connective tissue proper
1- loose
2- dense
what three categories are under the connective tissue proper
areolar
adipose
reticular
what are the three categories under dense connective tissue proper
regular
irregular
elastic
what are the three types of cartilage and describe them
1) hyaline= same as artiulcar cartilage, tends to find this cartilage on the surfaces of bone to stop other bones from damaging each other
2) fibrocartilage= more fibrous than hyaline, has more collagen and tends to be found in structures that are more stiffer eg the meniscus
3) elastic= cartilage with more elasticity in it
identify the 4 components of connective tissue
1- connective tissue proper
2- cartilage
3- bone
4- blood
what are the two main categories that the connective tissue structure consists of
- cells
- extracellular matrix
what is relaxed collagen
muscle looks more wavy
describe loaded collagen
muscle looks more organised meaning the more you pull on the muscle the more tension you will feel
describe the ligament composition
1) cells which are mostly fibroblasts ( 10-20%)
2) extracellular matrix ( 80-90%)
- water consists of 70% of the extracellular matrix
- solids make up 30% of the extracellular matrix
3) collagen composition 90% type 1
- type 1= biggest and strongest type which means more strength
- type 3= collagen tends to be smaller and weaker
4) variable elastin content
describe blood vessel supply in ligaments
- relatively sparse but important
- slower healing rates than muscle
describe innervation (communication with the nervous system) in the ligaments
- mechanoreceptors
- proprioception - bodies awareness of its position in space for example an act sprain where there is inhibition of quad and activation of hamstring motor neurone
define nociceptors
pain receptors
describe ligaments as mechanoreceptors
ACL- hamstring reflex= can protect all from damage
reflex= automatics, sensory receptors detect goes to the spinal cord and travels straight to the muscle to reflex
describe articular cartilage (x3)
- 1-7mm thick
- devoid of innervation
- no blood vessels, low cell density meaning it doesn’t heal very well
define fibrocartilage ( x3)
- type 1 collagen
- little movement
- IV discs
describe elastic (x2)
- more elastin ( greater ability to deform and return to its original length
- epiglottis ( structure in throat to prevent food from going into lungs)
list the cartilage composition
- cells= 10%
- chondroblasts = help build cartilage tissue
- chondrocytes= mature the cartilage cells
- extracellular material = 90%
- 60 -85% of ECM is water
- 10-30% of ECM is collagen
how does articular cartilage have nutrition
- compressive loading squeezes fluid out of the cartilage
- unloading allows to flow back into cartilage
- nutrient from synovial fluid is drawn into the cartilage
define a meniscus
helps to ‘smooth’ the distribution of contact forces
what are the 5 elements in all synovial joints
1- synovial fluid
2- articular cartilage
3- articular joint capsule
4- synovial membrane
5- blood vessels
6- sensory nerves
what are the 6 factors that occur within joints and increased ageing
1) decreased water content in cartilage therefore less nourishment is occurring
2) increase in calcium deposits therefore can result in joint stiffness
3) increased collagen linkage, particularly ligaments
4) cartilage thinning
5) increased fibrous material
6) reduction in synovial membrane
