Download Ch8 Joints-1

Joints (Articulations)
Classification: Function, Structure, Range of
Movement, Specific Names
 Weakest part
 Functions:
 mobility
 Hold skeleton together
 Classification: Function
(amount of movement),
Structure (Tissue), and
Range of movement,
CH8 JOINTS
Functional Classification of Joints:
 amount of movement
 3 functional classes:
 Synarthroses: (Stop)
 Amphiarthroses: (A little)
 Diarthroses: (Drive)
Structural Classification of Joints-- 3
 Tissue binding bones & if joint cavity present
 Fibrous joints
 Cartilaginous joints
 Synovial joints – bones articulate in cavity; all
diarthroses
Each structural
class has
subclasses…
FIBROUS JOINTS – usually synarthrotic
 * Sutures: short conn. T. fibers
 All Synarthroses
 Syndesmoses: ligaments, bands
or cords of conn. T.
 Syn or Amphiarthroses
 Gomphoses: peg in socket
 Synarthroses
Cartilaginous Joints
 * Symphyses: disc of
fibrocartilage
 Amphiarthrotic
 Synchondroses: band of
hyaline C.
 Synarthrotic
** Synovial Joints **
 freely movable diarthroses
6 Elements:
1. Articular Cartilage:
Synovial Joints: General Structure
2. Joint (synovial) Cavity
3. Articular Capsule –
 Outer: dense fibrous
 Inner Synovial
Membrane
4. Synovial fluid –
 contains phagocytes &
Hyaluronic Acid
 Functions:
 “Weeping lubrication”
5. Reinforcing ligaments –
often thickened part of fibrous
capsule
6. Nerves & Blood Vessels
Synovial Joints …
Bursae & Tendon Sheaths
 Bursae – flattened, fibrous sacs
 Function:
 Tendon sheath – elongated bursa; wraps around a tendon
- Function:
- multiple tendons
Table 8.2.1
Table 8.2.2
Table 8.2.3
Synovial Joints …
Factors Influencing Stability
 Articular surfaces – shape
 Minor role
 Movement types
 Shallow vs. deep
 Ligaments
 Moderate role
 prevent excessive/undesirable motion
 Undue tension can cause stretching breakage
 Muscle tone & Tendons
 Most important
 Muscle tone
 Muscles cross joints: two attachments:
 Origin:
 Insertion:
 CLASSIFICATION OF SYNOVIAL JOINTS
 Range of Motion
 Specific Names based on Anatomy
Synovial Joints …
Range of Motion-- Planes
 Nonaxial – slipping movements only
 Uni: small slipping
 Bi
 Multi
TYPES OF MOVEMENTS
(Examples: Fig. 8.5 & 8.6)
Gliding Movements
 = flat bone surfaces slip past each other
Angular Movement- = Increase or decrease angle
 Flexion:
 Sagital plane
 Extension:
 Hyperextension
 Foot– special terms
 Dorsiflexion: move foot closer to tibia
 Plantar Flexion: point toes
Angular Movement …
 Abduction — ________ midline
or median plane
 Adduction — _____ midline
 Circumduction — movement in a
cone
Rotation
 = bone turns around its
own long axis
 Examples
 Between first two
vertebrae
 Hip and shoulder joints
Figure 8.5g
Special Movements
 Supination: end of radius moves around end of ulna; to
anatomical position
 “hold soup”
 Pronation
 Inversion: moves bottom of foot medially/inward
 Eversion
 Protraction: move mandible anteriorly
 Retraction
 Elevation: close jaw
 Depression
 Opposition– Thumb
meets fingers
Types of Synovial Joints–
Examples = Figure 8.7
Plane Joint
 Flat surfaces
 slipping or gliding movements
 nonaxial
Figure 8.7a
 Hinge joints
 Cylindrical projections fits
into a trough-shaped
surface
 Uniaxial: flexion &
extension
 Examples:
Pivot Joints
 Rounded bone end protrudes
into a ring
 Ligaments can act as ring
 uniaxial
 Examples:
Condyloid or Ellipsoidal Joints
 Oval articular surface fits into a
complementary oval depression
 Biaxial joints—all angular
motions
 Examples:
Saddle Joints
 greater movement
 Articular surface w/ both
concave & convex surfaces
 Example:
Ball-and-Socket Joints
 spherical or hemispherical head articulates with a cuplike
socket
 Multiaxial joints– all movement
 Examples:
Synovial Joints are categorized by allowable
movements
Short, gliding
movements
Angular movement
in one plane
Rotation around
long axis
Figure 5.30a–c
Types of Synovial Joints cont.
Side to Side
Back and Forth
Side to Side
Back and Forth
Side to Side, BackFigure
and5.30d–f
Forth,
Rotation too!
Inflammatory Conditions of Joints
STUDENTS DO
 Bursitis
 Tendonitis
 Sprain
Clinical Forms of Arthritis – inflammation or
degeneration of joints STUDENTS DO
 Osteoarthritis – worn cartilage replaced by bone
 Probably related to normal aging (most common)
Clinical Forms of Arthritis – inflammation or
degeneration of joints
STUDENTS DO
 Rheumatoid arthritis –
scar tissue can fuse joints
 Autoimmune disease—
immune system attacks
joints
 Gouty arthritis – uric acid
crystallizes inside joints
END
Elbow Joint-- movement
Rotatable Elbow video
Elbow Joint
 The 6 elements
 Angular ligament
 Surrounds head of
radius
 Two capsular ligaments
restrict side-to-side
movement
 Ulnar collateral
ligament
 Radial collateral
ligament
Figure 8.11a The elbow joint.
Articular
capsule
Synovial
membrane
Humerus
Synovial cavity
Articular cartilage
Fat pad
Tendon of
triceps
muscle
Bursa
Coronoid process
Tendon of
brachialis muscle
Ulna
Trochlea
Articular cartilage
of the trochlear
notch
Median sagittal section through right elbow (lateral view)
Figure 8.11b The elbow joint.
Humerus
Anular
ligament
Radius
Lateral
epicondyle
Articular
capsule
Radial
collateral
ligament
Olecranon
Ulna
Lateral view of right elbow joint
Figure 8.11d The elbow joint.
Articular
capsule
Anular
ligament
Humerus
Coronoid
process
Medial
epicondyle
Radius
Ulnar
collateral
ligament
Ulna
Medial view of right elbow
PLAY
Animation: Rotatable Elbow
Figure 8.11c The elbow joint.
Humerus
Anular
ligament
Medial
epicondyle
Radius
Articular
capsule
Ulnar
collateral
ligament
Coronoid
process
Ulna
Cadaver photo of medial view of right elbow
A&P Flix™: The Elbow Joint and Forearm: An
PLAY
overview
Figure 8.10e The shoulder joint.
Acromion
(cut)
Head of
humerus
Muscle of
rotator
cuff (cut)
Anterior view of an opened shoulder joint
Glenoid
cavity of
scapula
Capsule of
shoulder
joint
(opened)
Figure 8.10c The shoulder joint.
Acromion
Coracoacromial
ligament
Subacromial
bursa
Coracohumeral
ligament
Greater
tubercle
of humerus
Transverse
humeral
ligament
Tendon sheath
Tendon of
long head
of biceps
brachii
muscle
Anterior view of right shoulder joint capsule
Coracoid
process
Articular
capsule
reinforced by
glenohumeral
ligaments
Subscapular
bursa
Tendon of the
subscapularis
muscle
Scapula
Figure 8.10d The shoulder joint.
Acromion
Coracoid
process
Articular
capsule
Glenoid cavity
Glenoid labrum
Tendon of long
head of biceps
brachii muscle
Glenohumeral
ligaments
Tendon of the
subscapularis
muscle
Scapula
Posterior
Anterior
Lateral view of socket of right shoulder joint,
humerus removed
Figure 8.12a The hip joint.
Coxal (hip) bone
Articular cartilage
Acetabular labrum
Ligament of the
head of the femur
(ligamentum teres)
Femur
Synovial cavity
Articular capsule
Frontal section through the right hip joint
Figure 8.12b The hip joint.
Acetabular
labrum
Synovial
membrane
Ligament
of the head
of the femur
(ligamentum
teres)
Head
of femur
Articular
capsule (cut)
Photo of the interior of the hip joint, lateral view