ARTHROLOGY Flashcards
What is a joint?
- union bw 2 or more bones
What is a joint classified by?
- histology (tissue type: fibrous, cartilaginous, synovial)
- amt of movement available (immobile, slightly mob, freely mob)
Structure of Fibrous joints
- bones are connected by dense fibrous CT, with little or no movem bw the bones
Eg of Fibrous joint
- suture
- syndesmosis
Fibrous joint - Suture
where is it found?
structure?
movement?
- F: skull
- S: bones linked by short fibres of CT
- M: no movement
Fibrous joint - Syndesmosis
where is it found?
structure?
movement?
- F: forearm + leg
- S: bones are linked by longer bands of CT
- M: slightly mobile
Structure of Cartilaginous Joints
- bones are united by cartilage. There are two types: primary (synchondroses) and secondary (symphyses).
Cartilaginous joints - Primary / Synchondrosis
where is it found?
structure?
movement?
- F: epiphyseal plates (where bone growth occurs)
- S: hyaline cartilage, eventually ossifies
- M: immob
Cartilaginous joints - Secondary / Symphysis
where is it found?
structure?
movement?
- F: pubic symphysis, intervertebral discs
- S: bones joined by fibrocartilage
- M: slightly mobile
Hip Joint
What is a synovial joint?
What movement?
- joint cavity containing lubricating synovial fluid
- freely movable
Eg of Synovial joints
- ball and socket (hip joint)
- hinge (elbow)
- pivot (bw C1 + C2 vertebrae)
- saddle (thumb)
- condyloid (wrist)
- plane/gliding joint (tarsal)
What is a uniaxial movement?
- 1 pair of movement eg. hinge, pivot
What is a multi-axial movement?
- 3 pairs of movements eg. ball + socket, plane
Active movement
- produced by muscle contraction
Passive movement
- produced by an ext force
Passive physiological movement
- movement can also be produced actively
Passive accessory
- movement X be produced actively
- moving articular surfaces w in a joint capsule
Angular Movements
- flexion + extension
- adduction + abduction
Rotational Movements
- med/lat rotation
- pronation + supination
Roll
- new point on one surface comes in contact w a new point on the other
Spin
- rotation around a fixed axis
Slide
- one surface moves linearly across another
What is the Closed Packed Position?
- ⬆est surface area of artiuclar surfaces
- lig + cap = taut
- extension
t/f.. ⬆ stab w ⬇ effort
hip: ext, med rot, abd
What is congurency?
- ⬆️est surface area contact bw 2 bones
hip: flexion, ext rot, abd
Structure of Ligaments
- bands of fibrous CT that join bones together in joints
Functions of Ligaments
- joint stability
- absorb shock
- limit excessive movement
- proprioception
Hip joint
Types of ligaments
- Intra-capsular (deep to capsule)
eg. ACL + PCL - Capsular (re-enforces capsule)
eg. ilio femoral ligament - Extra-capsular (sits outside the capsule)
eg. lateral collateral ligament
Structure of Bursae
- synovial fluid-filled sacs
Function of Bursae
- reduce friction
Structure of Articular Discs
- fibrocartilaginous pads bw articular surfaces of some synovial joints
5 functions of Articular Discs
- shock absorbers
- permit diff movements to occur in the joint
- aid mechanical fit
- restrain movement
- assist lubrication
Structure of Joint capsule
- encloses syn capsule
- fibrous CT
Function of Joint Capsule
- INCR stab
Hip Joint
What does the Synovial Membrane line?
- lines int surface of articular caspule + covers acet labrum
Function of Synovial Membrane
- secrete syn fluid/ lubrication
