type joints Flashcards
Joints
hold bones together but permit movement
Point of contact
– between 2 bones
– between carLlage and bone
– between teeth and bones
Arthrology = study of joints
Kinesiology = study of moLon
Structural classificaLon
is based on the presence or absence of a synovial cavity and type of connecting tissue:
– Fibrous – no synovial cavity; dense fibrous connecLve tissue; little to no movement; 3 structural types
– Cartilaginous – no synovial cavity; fibrocartilage or hyaline carLlage; liJle to no movement; 2 structural types
– Synovial – contain synovial cavity; hyaline cartilage called articular cartilage; free movement; 6 structural types
FuncLonal classificaLon based upon movement:
– Synarthrosis - immovable
– Amphiarthrosis - slightly movable
– Diarthrosis - freely movable
Fibrous Joint types
• Sutures:
– unite bones of the skull
– Synarthrosis joints
Function: shock absorption – add strength and decrease chance of bone fractures
Fibrous Joint types
o Syndesmosis:
• unite bones that are at greater
distance; denser then sutures
- e.g. ligament - amphiarthrosis joint
- e.g. gomphosis - synarthosis joints
Fibrous Joint types
o Interosseous membrane:
- unite neigbouring long bones;denser then syndesmosis
- Amphiarthrosis joint
- e.g. between fibula and Lbia or between radius and ulna
Cartilaginous Joint types
o Synchondrosis:
• Hyaline carLlage
- Synarthrosis joint
- e.g. epiphyseal plate or joints, between ribs and sternum
Function: permits growth
CarLlaginous Joint types
o Symphysis:
• Fibrocartilage
- Amphiathrosis joint
- e.g. intervertebral disc and pubic symphysis
- Synovial Joints :
- Separates articulating bones
- Diarthrosis joint
- Structure:
– Articular capsule
– Articular cartilage
– Synovial cavity
- Function: reduces fricLon and absorbs shock
Articular Capsule
• Structure: composed of two layers:
– outer fibrous capsule: extension of periosteum; irregular connecLve Lssue; tensile strength
– inner synovial membrane: areolar connecLve Lssue with elasLc fibers; secretes synovial fluid (hyaluronic acid; lubricates and nourishes arLcular carLlage); allows flexibility
• Function: encloses the synovial cavity and unites the arLculaLng bones
Special Features of Synovial Joints
Special Features of Synovial Joints
Planar:
- – bi-axial; bone surfaces are flat or slightly curved
- – side-to-side and back-and-forth gliding movements; rotaLon prevented by ligaments
- – e.g. intercarpal joints
Hinge:
– Uniaxial; convex/concave fit
– Flexion, extension and hyperextension movements
– e.g. knee, elbow, interphalangeal joint
Pivot:
Synovial Joint types
- – Monoaxial (allows only rotaLon around longitudinal axis); rounded surface of bone arLculates with ring formed by 2nd bone & ligament
- – SupinaLon, pronaLon; turning head side-to- side (NO)
- – e.g. proximal radioulnar joint
Ellipsoidal (Condyloid):
– Bi-axial; oval-shaped projecLon fits into oval depression
– flex/extend or abduct/adduct
– e.g. wrist and metacarpophalangeal joints
Saddle:
– Bi-axial; One bone saddled-shaped and the
other looks like it is signg in the saddle
– CircumducLon and opposiLon movement
– e.g. trapezium of carpus and metacarpal of the thumb
Ball and Socket:
– Multi axial; Ball fitting into a cuplike depression
– flexion/extension, abducLon/adducLon, rotation movement
– e.g. shoulder and hip joint (only these two)
Nerve and Blood Supply
- Nerves to joints are branches of nerves to nearby muscles
- Joint capsule and ligaments contain pain fibers and sensory receptors
- Blood supply to the structures of a joint are branches from nearby structures
– supply nutrients to all joint tissues except the articular cartilage which is supplied from the synovial fluid
fibrous joint
cartiiginous joints
synovial
