What is articulation?
The point of contact between bones, bone and cartilage, or bone and teeth.
What are the 2 major classification systems for joints?
-based on presence or absence of a synovial (joint) cavity and type of connecting tissue.
-Fibrous, cartilaginous or synovial
-based on degree of movement premitted
-Amphiarthroses (partially movable)
-Diarthroses (freely movable)
What are 3 types of fibrous joints?
3. Interosseous Membrane
What is a suture?
A fibous joint composed of a thin layer of dense fibrous CT that unites skull bones.
What ais synostosis?
A suture joint that has ossified.
What is syndesmosis?
Fibrous joint that has more fibrous CT than in a suture
What is a interosseous membrane?
A sheet of dense irregular CT joining 2 long bones (eg. radius and ulna)
A fibrous joint
What is a fibrous joint?
A joint that
-lacks a synovial cavity
-articulating bones are held together by fibrous CT
-they permit little or no movement
What is a cartilaginous joint?
A joint that
-lacks a synovial cavity
-articulating bones are connected by either fibrocartilage or hyaline cartilage
-allows little or noe movement
Explain the 2 types of cartilaginous joints.
-a cartilaginous joint in which the connecting material is hyaline cartilage.
-a cartilaginous joint in which the connecting material is a disc of fibrocartilage.
What are the 4 movements allowed by synovial joints?
1. Gliding movements
2. Angular movements
4. Special movements
What are the 5 angular movements that synovial joints allow?
List the 10 special movements that can occur ar some joints.
an upward movement of a part of the body.
a downward movement of a part of the body.
a movement of a part of the body anteriorly in the transverse plane.
a movement of a protracted part back to the anatomical position.
a movement of the soles medially at the intertarsal joints so that they face eachother.
a movement of the soles laterally at the intertarsal joints so that they face away from eachother.
The beding of the foot at the ankle in the direction of the superior surface.
the bending of the foot at the ankle joint in the direction of the plantar surface.
A movement of the forearm at the proximal and distal radioulnar joint in which palm is turned anteriorly or superiorly.
A movement of the forearm at the proximal and distal radioulnar joints in which the distal end of the radius crosses over the distal end of ulna, and palm is turned posteriorly or inferiorly.
What are the 6 subtypes of synovial joints?
1. ball-and-socket joints
2. hinge joints
3. pivot joints
4. condyloid/ ellipsodial joints
5. planar joints
6. saddle joints
The ball-shaped surface of one bone fits into the cuplike depression of another.
The conves surface of one bone fits into a concave surface of another bone.
Permits mainly side-to-side and back-and-forth gliding movements.
A round or pointed surface of one bone fits into a ring formed by another bone and a ligament.
Condyloid/ Ellipsoidal Joint
Convex oval-shaped projection fits into the concave depression on another bone.
Includes one bone whose articular surface is saddle-shaped and another bone whose articular surface is shaper like a rider sitting in the saddle.
What type of joint is freely movable?
(Diarthrosis = Freely Movable)
What type of cartilage covers the bones at synovial joints?
What is the function of articular cartilage?
-Reduces friction at joint during movement
- Helps to absorb shock
What is the articular capsule composed of?
1. outer fibrous capsule, may contain ligaments
2. inner synovial membrane
What is the function of the inner synovial membrane in the articular capsule?
Secretes a lubricating and joint-nourishing synovial fluid.
What does synovial fluid, secreted by the synovial membrane, do for joints?
Lubricates and reduces frition in joint and
supplies nutrients to, and removes metabolic wastes from, the joint.
What do ligaments hold?
bone to bone
What are the articular discs functions?
-Modifies the shape of the joint surfaces of the articulation bones.
-Helps maintain stability of joint
- Directs flow of synovial fluid to areas of greatest friction.
What is a sprain?
The forcible wrenching or twisting of a joint that stretches or tears its ligaments but does not dislocate the bone.
What is a strain?
A stretched or partially torn muscle.