Lab 10: Joints

Question 1

joints, or articulations

-what are they

Answer 1

How bones attached to one another. Only place movement can occur

Question 2

Classification of Joints - 2 types (with 3 subtypes each)

Answer 2

Functional:
-based on movement at joint
• synarthroses (immovable) joints
• amphiarthroses (slightly movable) joints
• diarthroses (freely movable) joints

Structural:
-type of connective tissue + if has joint cavity
• fibrous joints
• cartilaginous joints
• synovial joints.

Question 3

Fibrous Joints

Answer 3

• dense fibrous connective tissue
• very strong
• little or no movement.
• no joint cavity
• 2 Types: Sutures + Syndesmoses

Question 4

Sutures

Answer 4

– dense connective tissue
– synarthroses (immovable)
– Ex. joint between cranial and facial bones

Question 5

Syndesmoses

Answer 5

– dense connective tissue
– movement depends on length of connecting fibers
– example: distal articulation between tibia and fibula (immovable, best described as “give”)

Question 6

Cartilaginous Joints

Answer 6

• cartilage
• no joint cavity
• permit little or no movement
• 2 types: Synchondroses + Symphyses

Question 7

Synchondroses

Answer 7

– hyaline cartilage
– synarthroses (immovable) joints
– examples: costal cartilages of rib #1 and manubrium

Question 8

Symphyses

Answer 8

– fibrocartilage
– amphiarthroses (slightly movable) joints
– examples: intervertebral discs; pubic symphysis

Question 9

Synovial Joints

Answer 9

• Most joints in the body
• movement limited only by ligaments, muscles, tendons, or adjoining bones
• diarthroses (freely movable) joints
• joint cavity
• synovial fluid: lubricates joint, provides nourishment for the articular cartilage.

Question 10

Synovial joints - 6 categories

Answer 10

1) Plane (Gliding) Joints
2) Hinge Joints
3) Pivot Joints
4) Condyloid (Ellipsoid) Joints
5) Saddle Joints
6) Ball-and-Socket Joints

Question 11

Plane (Gliding) Joints

Answer 11

• articulating = flat
• nonaxial
• slight movement
• Ex. carpal-carpal, tarsal-tarsal

Question 12

Hinge Joints

Answer 12

• Convex –> concave
• monaxial
• flexion and extension
• Ex. : elbow/ankle/knee joint

Question 13

Pivot Joints

Answer 13

• Rounded surface –> ring-like surface
• monaxial
• rotation
• Ex. atlas –> axis

Question 14

Condyloid (Ellipsoid) Joints

Answer 14

• Oval Convex –>Oval concave
• biaxial
• flexion and extension, abduction and adduction, circumduction and rotation
• Ex. radius –> carpal bones

Question 15

Saddle Joints

Answer 15

• Each has both convex and concave areas
• biaxial
• flexion and extension, abduction and adduction, circumduction
• Ex. Thumb joint (carpal –> metacarpal bone)

Question 16

Ball-and-Socket Joints

Answer 16

• Ball like –> cup like
• biaxial
• flexion and extension, abduction and adduction, circumduction and rotation
• Ex. shoulder joint; hip joint

Question 17

Abduction

ABDuction

Answer 17

movement of limb away from the medial line

Question 18

Adduction

ADDuction

Answer 18

movement of limb toward medial line

Question 19

Flexion

2 special

Answer 19

decreases the angle between articulating bones

ankle joint Flexion:

• Dorsiflexion - toes point upward (stand on heels)
• Plantar flexion - toes point downward (tiptoe)

Question 20

Extension

Answer 20

increases the angle between articulating bones

Question 21

Hyperextension

Answer 21

the continuation of extension beyond anatomical position.

Question 22

Rotation

Answer 22

the movement of a bone around its own longitudinal axis without lateral displacement of the body part.

Question 23

Circumduction

Answer 23

movement in which one end of a limb remains relatively stationary while the distal end of the limb moves in a circle.

Question 24

Pronation

Answer 24

movement of the hand from a palm-up to a palm-down (prone) position.

Question 25

Supination

2 special

Answer 25

movement of the hand from palm-down to palm-up (supine) position.

Supination of foot:

• Eversion - soles turn outward (laterally)
• Inversion - soles turn inward (medially)

Question 26

bursae

Answer 26

flattened fibrous sacs, contain synovial fluid to help decrease friction on the shoulder where tendons and muscles cross the joint capsule.