JOINTS AND THE
SKELETON
THE HUMAN SKELETON IS
MULTI-FUNCTIONAL
•Gives structure to the body
•Provides for red and white
blood cell development
•Allows for movement in a
variety of directions, depending
on the type of joint
•Protects internal organs
Terminology
 Articulation (joint): the point at which two
bones meet or at which bone and cartilage
meet
 Arthrology: study of joints
 Kinesiology: study of movement
 Rheumatology: medical field devoted to
studying joint diseases and conditions
More Terminology
 Arthroscopy: procedure that involves the
examination of the interior of a joint using
an arthroscope (lighted instrument the size
of a pencil)
Disorders
Dislocation: displacement of articulating bones
from their normal position
 Rheumatism: painful state of a body structure
(joint, muscle, tendon, etc.)
 Arthritis: form of rheumatism which causes joint
inflammation
 Sprain: wrenching or twisting of a joint that may
tear ligaments
 Strain: stretched or partially torn muscle

Stating the obvious…
 Looser joints
• More movable/flexible
– More vulnerable to injury
 Tighter joints
• Less movable/flexible
– Less vulnerable to injury
Joint Classifications

Structural
Classification
• There are 3
• Based on the presence
or absence of a
synovial cavity
• Based on which type of
connective tissue is
present

Functional
Classification
• There are 3
• Based on degree of
movement
Structural Classes of joints
1. Fibrous
1. No cavity
2 Fibrous connective tissue
Ex: suture
2. Cartilaginous
1. No cavity
2. Cartilage connective tissue
Ex: epiphyseal plate
3. Synovial
1. Cavity present
2. Ligament connective tissue
Ex: shoulder, hip, etc.
Functional Classifications
1.
2.
3.
Synarthrosis: immovable joint
Amphiarthrosis: slightly movable joint
Diarthrosis: freely movable joint
Fibrous joints (synarthrotic)
 Sutures
• Irregular, interlocking edges
• Immovable
Ex: skull sutures
 Syndemoses
 Gomphoses
Cartilaginous joints
(amphiarthrotic)
 Synchondroses
 Symphysis
• Articulating bones are covered with hyaline
cartilage
Ex: pubis symphysis; intervertebral joints
Synovial joints (diarthrotic)
 Contain ligaments
 Contain menisci: pads of cartilage between
bones
 Contain bursae: fluid-filled pouches that
reduce joint friction
• Inflammation = bursitis
Types of diarthrotic/synovial joints
 Planar
 Hinge
 Pivot
 Condyloid
 Saddle
 Ball and socket
Planar joint
 flat or slightly curved
 Ex: intercarpal, sternoclavicular
Hinge joint
 one convex & one concave
 Ex: elbow, knee, ankle, wrist
Pivot joint
rounded bone covered by a ring-shaped
bone
 Ex: atlas & axis, radius-ulna

Condyloid joint
 one convex, oval-shaped and one concave
oval-shape
 Ex: wrists, jaw
Saddle joint
 saddle shape
 Ex: thumb
Ball and socket joint
ball-like surface that fits into a cup-like
surface
Ex: shoulder, hip
Diarthrotic/Synovial joint
movement types

Flexion: decrease in an angle at a joint
• All joints except planar

Extension: increase in an angle at a joint
• All joints except planar


Hyperextension: extension beyond anatomical position
Abduction: movement away from midline of body
• Condyloid, saddle, ball & socket

Adduction: movement toward the midline of the body
• Condyloid, saddle, ball & socket

Rotation: bone revolving around its own longitudinal axis




Pivot, ball & socket
Circumduction: movement in a circular path
Inversion: the plantar surface facing medially
Eversion: the plantar surface facing laterally
Types of movement
Other special movements

Elevation: upward movement
• Ex: closing the mouth; raising shoulders

Depression: downward movement
• Ex: opening the mouth; lowering shoulders

Dorsiflexion: bending the foot dorsally
• Ex: stand on heels

Plantar flexion: bending the foot toward the plantar
surface
• Ex: point the toe




Supination: palms turned forward or upward
Pronation: palms turned backward or downward
Protraction: movement forward
Retraction: movement backward
Special Movements
NAME THE JOINT
On the following slides:
•name the type of joint
•decide what kind of
motion occurs there
NAME THE JOINT
Hinge joint
Allows movement back
and forth in one plane.
NAME THE JOINT
Ball and socket joint
Allows for most range of
movement.
NAME THE JOINT
Pivot joint
Rotation of the head on the
spine
NAME THE JOINT
Planar joints
Bones slide over one
another.
NAME THE JOINT
Suture
No movement
NAME THE JOINT
Hinge joint
Allows movement back
and forth in one plane.
Fractures

A CRACK OR BREAK OF A
BONE
TYPES OF FRACTURES (P. 136)
 SIMPLE:
COMPLETE BREAK WITH NO DAMAGE
TO SKIN
 COMPOUND: BREAK IN BONE THAT RUPTURES
THROUGH SKIN
 GREENSTICK: CRACK IN A BONE
 TRANSVERSE: BREAK IS AT RIGHT ANGLE
 OBLIQUE: BREAK IS AT AN ANGLE
FRACTURE (continued)
 COMMINUTED: BONE SPLINTERED OR CRUSHED
AND BONE FRAGMENTS ARE PRESENT
 FISSURE: INCOMPLETE LONGITUDINAL BREAK
 SPIRAL: SEVERE TWISTING OF A BONE CAUSES
BREAK
• COMMON IN SKIING & SKATING ACCIDENT
Fracture Video
Interactive Table
 Table 1
 Table 2