There are three main classification schemes for joints in the body: 1. Structural classes include fibrous, cartilaginous, and synovial joints. 2. Functional classes include synarthrosis (immovable), amphiarthrosis (slightly movable), and diarthrosis (freely movable). 3. Six classes of synovial joints are gliding, hinge, pivot, condyloid, saddle, and ball-and-socket, which permit different degrees of movement through their structural designs.

1. Objective 11
• Define “articulation” and discuss the
classification schemes for the joints of the
body: functional classes (synarthrosis,
amphiarthrosis, diarthrosis) and structural
classes (fibrous, cartilaginous, synovial).
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2. Objective 11/12 Articulations
An articulation (joint) occurs whenever two or more bones meet.
There are two classification schemes for articulations:
A. Structural Classes:
• are based on the type of
intervening tissue holding the
bones
• there are three main
structural categories
• Fibrous
• Cartilaginous
• Synovial
B. Functional Classes:
• Based on the degree of
movement permitted at the
joint
• Synarthrosis:
– immoveable joints
• Amphiarthrosis
– slightly moveable joints
• Diarthrosis
– freely moveable joints
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3. 1. Fibrous Joints
- the bones are joined by fibrous connective tissue
- the amount of movement permitted depends on the length of the fibers holding
the bones together
1a. Sutures
- short fibers hold the bones together
- fontanels in infants
- these joints ossify (form a syntosis) in adults
- are immoveable joints
What type of bone formation?
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4. Intramembraneous Ossification
via fibrous membrane
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5. Fibrous Joints:
Sutures
• Rigid, interlocking joints
• Immovable joints for protection of brain
• Contain short connective tissue fibers
• Allow for growth during youth
• In middle age, sutures ossify and fuse
– Called Synostoses

6. 1b. Syndesmosis: longer bands of fibers connect the bones; these
bands are called ligaments or
interosseous membranes
Slightly moveable-Amphiarthrotic
Immoveable-SynarthroticDistal radius and ulna
Distal tibia/fibula
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7. 1c. Gomphosis: the periodontal ligament holds the tooth in
its alveolar socket
Immoveable
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8. © 2013 Pearson Education, Inc.
Synchondroses
Bones united by hyaline cartilage
Epiphyseal
plate (temporary
hyaline cartilage
joint)
Sternum
(manubrium)
Joint between first
rib and sternum
(immovable)
2. Cartilaginous Joints
- held together by hyaline or fibro cartilage; immoveable (syn-) or slightly moveable
(amphi-)
Symphyses
Bones united by fibrocartilage
Body of vertebra
Fibrocartilaginous
intervertebral disc
(sandwiched between
hyaline cartilage)
Pubic symphysis
most of these joints eventually ossify (form a syntosis)

9. Articular cartilage: hyaline cartilage that covers
the ends of the
articulating bones
Joint cavity: potential space that lies
(synovial) between the articulating
bones; this space is filled with
synovial fluid
Articular capsule: has two portions:
fibrous capsule: dense irregular
connective tissue that holds the
bones together
synovial membrane: inner
structure that secretes
synovial fluid
1
4
3
2
9

10. Ligament
Joint cavity
Articular (hyaline)
cartilage
Fibrous
layer
Synovial
membrane
(secretes
synovial
fluid)
Articular
capsule
Periosteum
1
4
3
2
3. Synovial Joints
- highly innervated, complicated structure; all
moveable (diarthrotic)
Articular cartilage: hyaline cartilage that
covers the ends of articulating bones
Joint (synovial) cavity: space between
articulating bones; this space is filled
with synovial fluid
Articular capsule: has two portions:
fibrous capsule: dense irregular CT that
holds bones together
synovial membrane: inner structure that
secretes synovial fluid

11. Reinforcing Ligaments
Joint Cavity space between articulating
bones; filled with synovial fluid
Articular (hyaline) cartilage
Fibrous
layer
Synovial
membrane
(secretes
synovial
fluid)
Articular Capsule::
FC: dense irregular CT that holds bones
together
SM: inner structure that secretes synovial fluid
Periosteum
1
4
3
2
3. Synovial Joints
- highly innervated, complicated structure; all
moveable (diarthrotic)

12. Synovial fluid: viscous fluid (yolk-like) that is found
in the joint cavity; functions
include:
1. Lubricate the joint surfaces
and reduce friction
2. Helps to nourish articular
cartilage
3. Phagocytic cells keep
the joint free of debris
Reinforcing dense, regular connective tissue
Ligaments: that connects the articulating
bones
intrinsic (capsular) ligaments
are parts of the joint capsule
extrinsic (extracapsular) ligaments
lie external to the joint capsule
intracapsular ligaments are deep to
the joint capsule
12

13. Objective 13 Additional Synovial Structures
Bursae/Tendon Sheaths/Menisci
Bursae: flattened fibrous sac lined with synovial membrane and filled with
synovial fluid
are inserted at strategic points to protect soft tissues from being
damaged while rubbing over bone
Tendon Sheaths: function like bursae, but are elongated and are wrapped around
tendons
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14. © 2013 Pearson Education, Inc.
Figure 8.4b Bursae and tendon sheaths.
Bursa rolls
and lessens
friction.
Humerus head
rolls medially as
arm abducts.
Humerus moving
Enlargement of (a), showing how
a bursa eliminates friction where
a ligament (or other structure) would
rub against a bone

15. 15
Menisci:
fibrocartilaginous pads that are found within
the joint cavity of some joints (knee)
Function:
1. Help protect the articular surfaces
2. Help to improve the fit of articular
surfaces that are not
congruent
Labrum: similar to the meniscus but located
in the shoulder or hip joint
Additional Structures:

16. Objectives 15 and 16 Joint Range of Motion
A. Range of motion:
movement at a joint ; can
occur in a variety of
directions or planes; and is
determined by:
1. The shapes of the articulating
surface
2. The pressure of ligaments and
tendons
3. The presence of adjacent tissue
B. Terms for range of motion:
Non-axial: non-directional movement;
slipping movements only
Uniaxial: movement in one plane
Biaxial: movement in two planes
Multiaxial: movement in three planes
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17. C. Specific Movements
• Gliding:
- When flat or nearly flat articular
surfaces slip or glide over each
other
- Examples are intertarsal,
intercarpal, intervertbral (at
articular processes) and sterno-
clavicular joints
• Protraction/Retraction:
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• Elevation/Depression:

18. Angular Movements
-the angle between two bones increases or decreases
Flexion: movement in a sagittal plane so that the angle between two
bones is decreased
Extension: movement into anatomic position from a flexed position
(increases ventral angle)
Hyperextension: extension beyond anatomic position
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19. 19

20. 20

21. • Six types, based on shape of articular surfaces:
– Plane
– Hinge
– Pivot
– Condylar
– Saddle
– Ball-and-socket
Objective 17
Classes of Synovial Joints

22. Gliding
Plane joint Nonaxial movement
Ex: Intercarpal/intertarsal joints, articularr suface of vertebral joints
Hinge joint Uniaxial movement
Ex: Elbow & interphalangeal joints
Flexion and extension
Pivot joint Uniaxial movement
Rotation
Ex: Proximal radioulnar joints, atlantoaxial joint
Condylar joint Biaxial movement
Ex: Metacarpophalangeal (knuckle) & wrist joints
Flexion and
extension
Adduction and
abduction
Flexion and
extension
Adduction and
abduction
Ex: Carpometacarpal joints of the thumbs
Saddle joint Biaxial movement
Ex: Shoulder joints and hip joints
Flexion
extension
Adduction
abduction Rotation
Ball-and-socket joint Multiaxial movement
Types of Synovial Joints

23. There are six classes of synovial joints:
Class Movement Permitted Structure
Gliding (Plane. Non-axial flat or slightly curved articular
Arthrodia) surface
Examples include intercarpal and intertarsal joints; joints between the vertebral
articular processes; sternoclavicular joints
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24. Class Movement Permitted Structure
Hinge (ginglymus) uniaxial; flexion/extension convex or cylindrical
projection of one bone
fits into a concave or
cylindrical groove of
another bone
Examples include the elbow, knee and interphlangeal joints
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25. Class Movement Permitted Structure
Pivot (trochoid) uniaxial; rotation only a rounded or conical surface
of one bone fits into a
“sleeve” or ring of bone or
ligaments
Examples include the joint between the atlas and axis; proximal radius and
ulna
C1 Atlas C2 Axis
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26. Class Movement Permitted Structure
Ellipsoidal biaxial; circumduction the oval articular surface of
(condyloid) one bone fits into a complex
concavity of another
Examples include the radiocarpal joint; metacarophalangeal joint;
atlanto-occipital joint
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27. Class Movement Permitted Structure
Saddle (sellaris) biaxial; circumduction but a structured like an ellipsoidal
greater degree of movement is joint
permitted than in an ellipsoidal
joint
Example is the carpometacarpal joint of the thumb
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28. Class Movement Permitted Structure
Ball and Socket multiaxial a spherical head or
(Spheroid) hemispherical head of a bone
fits into the concave socket of
another bone
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29. Objective 16 Selected Synovial Joints
A. Shoulder Joint:
- a ball and socket with great range of motion
Bones: arm bone (humerus),
shoulder blade (scapula), and
collarbone (clavicle).
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30. Rotator Cuff Muscles:
SITS
Supraspinatus
Infraspinatus
Teres minor
Subscapularis
The rotator cuff muscles and triceps brachii (long head)
provide support
?
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31. 31

32. B. The Hip Joint
- ball and socket with less range of motion, limited by the deep
socket of the acetabulum and strong ligaments
- Weight bearing joint
The acetabular labrum makes
the acetabulum deeper!
Reinforcing ligaments:
ligamentum teres
ischiofemoral ligament
pubofemoral ligament
ilio femoral ligament
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33. C. The Elbow Joint
- A hinge joint with substantial anterior/posterior movement
- Radial and ulnar collateral ligaments limit side to side motion
- Bones: humerus, radius, ulnar
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34. D. The Knee Joint
- a modified hinge joint that allows extension and some rotation
- An incomplete articular capsule is found on the lateral and posterior
surfaces
- Extracapsular ligaments include the fibular and tibial collateral
ligaments, oblique popliteal ligament and arcuate popliteal ligament
- Intracapsular ligaments are the ACL and the PCL
http://www.youtube.com/watch?v=uuoj_HFG5Z0
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35. YouTube - Knee Ligament Anatomy Animation
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36. Objective 18 Joint Disorders
Disorder Cause(s) Characteristics
Rheumatoid arthritis autoimmune inflammation of the synovial
membranes causes them to thicken
and accumulate fluid leading to
pain
often involves interphalangeal
wrist and knee joints
mild cases result in a reduced
range of motion because of
inflammation
severe cases may cause the joint
to fuse (ankylosis) and become
immoveable
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37. Rheumatoid Arthritis
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38. Disorder Cause Characteristics
Osteoarthritis disease of cartilage progressive deterioration of articular
cartilage in weight bearing joints
such as the knee, the spine and hips
bone spurs can grow that inflame
surrounding tissues
associated with aging; may be
exacerbated by obesity, athletics
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39. Disorder Cause Characteristics
Gouty arthritis sodium ureate crystals irritation of articular cartilage causing
inflammation, swelling and pain
likely to occur in the joint at the base
of the big toe, the elbow, knee, hand
foot, ankle, arm or shoulder
effects primarily men of any age
precipitated by diet, diuretics, stress
and some antibiotics
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40. Disorder Cause(s) Characteristics
Bursitis joint injury or infection inflammation of bursae causing swelling,
pain, tenderness and a reduced range of
motion
most frequent in bursae near the shoulders,
hips, pelvis and knees
Dislocation traumatic joint injury, displacement of a bone from its joint
congenital joint causing swelling, pain and temporary
malformation paralysis of the joint
most common in fingers, and fairly connon
at the mandible, elbow, hip and knee
Tendinitis traumatic injury, poor painful inflammation of a tendon
causing posture and some tenderness and restricted movement
musculoskeletal disorders common sites are the shoulder, elbow and
achilles tendon
Sprain overuse or stress of a injury to ligaments resulting in tearing and
ligament stretching causes pain, swelling and
immobility common in wrists, ankles 40

41. Bursitis Images
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42.
Dislocation
Images
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