Lecture 4 - Articulations and Frames Flashcards
1
Q
What is an articulation?
A
- a place where two or more bones meet
2
Q
what are the three types of articulations?
A
- synarthrodial
- amphiarthrodial
- diarthrodial
3
Q
what are synarthrodial articulations?
A
- immovable joints
- where two bones “fuse” together
- ex: suture of the skull
4
Q
what are amphiarthoridal articulations?
A
- cartilaginous joints
- connected via fibrocartilage
- a small range of motion
- ex: intervertebral discs
5
Q
what are diarthrodial articulations?
A
- joints that allow the most forceful motions
- large range of motion
- ligaments and tendons are present
- ex: knees, hips, elbows
6
Q
what is articular cartilage?
A
- covers bearing surfaces of bones
- protects bones where they hit to reduce friction (heat and wear)
7
Q
what is synovial fluid?
A
- fluid found in the joint space
- lubricates and nourishes cartilage
- keeps friction low
8
Q
what is the joint capsule?
A
- a watertight enclosure on the joint
- keeps the synovial fluid in
- pressurized
9
Q
what are ligaments?
A
- hold bone to bone
- tension only
- strain = elongation
- stress = load
- sustains less stress
10
Q
what are tendons?
A
- hold muscle to bone
- tension only
- strain = elongation
- stress = load
- sustains more stress
11
Q
how are tendons and ligaments affected by age?
A
- stiffer with age
- warming up becomes more important with age (to prevent strains)
12
Q
what is “stability”?
A
- how easy it is to disrupt or injure a joint
- less stability = more likely to injure
13
Q
what are the three factors that influence joint stability?
A
- bony congruency (how well the bones fit together)
- tightness and strength of ligaments
- strength and angles of muscle attachments
14
Q
what is bony congruency?
A
- how well the bones fit together
- stable joints have good bony congruency
15
Q
what is tightness and strength of ligaments?
A
- lots of ligaments = tight and strong
- high stability
- once injured, unstable and difficult to fix
