joints

Question 1

What are joints

Answer 1

places of contact between
two or more bones
bones and cartilage
bones and teeth

Question 2

Other words for joints

Answer 2

articulation or arthrosis

Question 3

how are joints classified?

Answer 3

structure and function

Question 4

Synarthrotic joints

Answer 4

immovable;
can be fibrous or cartilaginous

Question 5

amphiarthrotic joints

Answer 5

somewhat movable;
can be fibrous or cartilaginous

Question 6

diarthrotic joints

Answer 6

freely movable; all synovial joints

Question 7

Structural classification

Answer 7

Is there a joint cavity?
what type of connective tissue is involved?

Question 8

Fibrous joints

Answer 8

– No joint cavity
– Bones held together by dense irregular connective tissue
– Syndesmoses, Sutures, Gomphosis

Question 9

Cartilaginous joints

Answer 9

– No joint cavity
– Bones joined by cartilage
– Symphysis, Synchondrosis

Question 10

Synovial joints

Answer 10

– Have joint cavity
– Bones joined by ligaments with fluid-filled joint cavity separating bone surfaces
– Plane, Hinge, Pivot, Condylar, Saddle, Ball & Socket

Question 11

Fibrous Joints – Gomphosis

Answer 11

• Articulations between teeth and
  dental alveoli of alveolar processes
• Tooth held in place by fibrous
  periodontal ligament
• Function as synarthroses

Question 12

Fibrous Joints - Suture

Answer 12

• Articulation between some skull bones
• Bones united by thin layer of dense irregular connective tissue
• Function as synarthroses
• Some become ossified synostoses in older adults

Question 13

Fibrous Joints – Syndesmosis

Answer 13

• Bones united by varying amount of dense irregular connective
  tissue, usually a ligament or membrane
• Function as amphiarthroses
  between fibula and tibia

Question 14

Cartilaginous Joints – Synchondrosis

Answer 14

• Bones united by hyaline cartilage
• Function as synarthroses
  ribs connected to spine

Question 15

Classification of Synovial Joints

Answer 15

– Shapes of joint surfaces
▪ Flat
▪ Concave/convex

– Movements allowed
▪ Uniaxial joint: Bone moves in just one plane or axis
▪ Biaxial joint: Bone moves in two planes or axes
▪ Triaxial joint: Bone moves in three planes or axes

Question 15

Cartilaginous Joints – Symphysis

Answer 15

• Bones united by fibrocartilage
• Function as amphiarthroses
  pubic joint

Question 16

Synovial Joints – Plane Joint

Answer 16

• Flat articular surfaces
• Many are biaxial: back-and-forth and side-to-side movements
• Some are triaxial: back-and-forth, side-to-side, rotation movements

Question 17

Synovial Joints – Hinge Joint

Answer 17

• Convex surface within concave surface
• Uniaxial: flexion-extension
  humerus and ulna

Question 18

Synovial Joints – Saddle Joint

Answer 18

• Convex and concave surfaces resembling saddle shape
• Biaxial: flexion-extension and abduction-adduction

Question 18

Synovial Joints – Pivot Joint

Answer 18

• Bone with rounded surface fits into ligament ring
• Uniaxial: rotation on longitudinal axis
  radius and ulna

Question 19

Synovial Joints – Condyloid Joint

Answer 19

• aka ellipsoid joint
• Oval, convex surface within oval, concave surface
• Biaxial: flexion-extension and abduction-adduction

Question 20

Synovial Joints – Ball-and-Socket Joint

Answer 20

• Spherical head of one bone fitting into cuplike socket
• Triaxial: flexion-extension, abduction-adduction, rotation

Question 21

Gliding

Answer 21

– Two opposing surfaces sliding back-and-forth or side-to-side
– Little change in angle between bones
– Typically occurs along plane joints

Question 22

Flexion

Answer 22

– Decreases the angle between bones (brings bones closer together)

Question 23

Extension

Answer 23

– Increases the angle between bones (opposite of flexion)

Question 24

Hyperextension

Answer 24

– Extension beyond normal range of motion
– Possible with extensively mobile joints or an injury

Question 25

Abduction

Answer 25

– Lateral movement of body part away from the midline

Question 26

Adduction

Answer 26

– Medial movement of body part toward the midline

Question 27

Lateral flexion

Answer 27

– Trunk of body moving laterally

Question 28

Circumduction

Answer 28

– Flexion, abduction, extension, adduction, and rotation in succession
– Proximal end of appendage relatively stationary
– Distal end makes a circular motion

Question 29

Lateral rotation

Answer 29

– Turns anterior surface of bone laterally

Question 30

Medial rotation

Answer 30

– Turns anterior surface of bone medially

Question 31

Pronation

Answer 31

– Medial rotation of forearm so palm turns posteriorly

Question 32

Supination

Answer 32

– Lateral rotation of forearm so palm turns anteriorly

Question 33

Elevation

Answer 33

– Superior movement of a body part

Question 34

Depression

Answer 34

– Inferior movement of a body part

Question 35

Protraction

Answer 35

– Anterior movement along transverse plane

Question 36

Retraction

Answer 36

– Posterior movement along transverse plane

Question 37

Dorsiflexion

Answer 37

– Bending foot in direction of dorsal surface (toes point superiorly)

Question 38

Plantar flexion

Answer 38

– Bending foot in direction of plantar surface (toes point inferiorly)

Question 39

Inversion

Answer 39

– Sole turns medially

Question 40

Eversion

Answer 40

– Sole turns laterally

Question 41

Opposition

Answer 41

– Movement of thumb toward tips of fingers at carpometacarpal joint
– Enables the thumb to grasp objects

Question 42

Reposition

Answer 42

– Opposite movement