Chapter 8 Key Terms
Abduction
Circumduction
Elevation
Extension
Inversion
Protraction
Rotation
Gliding Joint
Amphiarthroses
1
Adduction
Dorsiflexion
Eversion
Flexion
Plantar Flexion
Retraction
Supination
Saddle Joint
Synarthroses
2
ANATOMY & PHYSIOLOGY
CHAPTER 8: ARTICULAR SYSTEM
3
Types of Joints

Articulation: where two or more bones meet

Joints are classified in groups based on structure (material
holding bones together) and function (degree of movement
allowed)

Synarthroses: no movement
 Suture:
bones connected by thin layer of connective tissue
 Syndesmosis:
 Gomphosis:
connected by ligaments between bones
conical process fits into a socket
4
Types of Joints

Amphiarthroses: slight movement
 Symphysis:
connected by a disk of
fibrocartilage
 Synchondrosis:
joints where
bones are connected by
hyaline cartilage
5
Types of Joints

Diarthroses or Synovial joints: freely moving joints
 Joint
capsule: encloses and protects the joint
 Articular
cartilage: provide smooth surface for articulating bones
 Ligaments:
capsule
holds the bones together and helps support the joint
6
Types of Movement

Flexion: decreasing the angle between bones

Extension: increasing the angle between bones

Hyperextensoin: increases joint angle beyond anatomical
position

Hyperflexion: decreases joint angle beyond normal range

Abduction: moving a bone or limb away from the midline of the
body

Adduction: moving a bone/limb toward the midline of the body
7
Types of Movement

Rotation: moving a bone around a central axis

Circumduction: moving bone in a way that the end describes
a circle, and the sides describe a cone in the air

Supination: moving the forearm so radius
and ulna are parallel

Pronation: moving the forearm so radius
and ulna are not parallel
8
Types of Movement

Eversion: moving the sole of the foot outward

Inversion: moving the sole of the foot inward

Protraction: moving part of body forward on plane parallel
with the ground

Retraction: moving part of body backward on plane parallel
with the ground

Elevation: raising part of the body

Depression: lowering a part of the body
9
Types of Movement

Opposition: movement when thumb and
fingers are brought together

Reposition: movement when digits return
to normal positions

Dorsiflexion: raising the foot at the ankle

Plantar flexion: pushing foot down at ankle
10
Synovial Joints

Ball-and-socket joint
 Ball
shaped head fits into a concave socket
 Multiaxial
 Allows

joint
the greatest range of motion (shoulder, hip)
Hinge joint
 Convex
surface fits into concave surface
 Allows
only flexion and extension
 Elbow,
knee, phalanges
11
Synovial Joints

Pivot joint
 Allows
 Axis

rotation in single plane
allows skull to rotate
Condyloid joint
 Oval-shaped
condyle fits into an
elliptical cavity
 Biaxial
joint
12
Synovial Joints

Saddle joint
 Allows
flexion and extension; abduction and adduction; and
opposition and reposition
 One
articular surface is concave in one direction and convex in the
other

Gliding joint
 Only
allows gliding movement
 Intervertebral
disks, carpals and tarsals