copyright © 2010 pearson education, inc. c h a p t e r 8 articulations powerpoint® lecture slides...
TRANSCRIPT
Copyright © 2010 Pearson Education, Inc.
C h a p t e r
8
Articulations
PowerPoint® Lecture Slides prepared by Jason LaPres
Lone Star College - North Harris
Copyright © 2010 Pearson Education, Inc.
An Introduction to Articulations
Articulations
Body movement occurs at joints
(articulations) where two bones connect
Joint Structure
Determines direction and distance of
movement (range of motion)
Joint strength decreases as mobility increases
Copyright © 2010 Pearson Education, Inc.
Classification of Joints
Two methods of classification
Functional classification is based on range
of motion of the joint
Structural classification relies on the
anatomical organization of the joint
Copyright © 2010 Pearson Education, Inc.
Classification of Joints
Functional Classifications Synarthrosis (immovable joint)
No movement
Fibrous or cartilaginous connections
May fuse over time
Amphiarthrosis (slightly movable joint) Little movement
Fibrous or cartilaginous connections
Diarthrosis (freely movable joint) More movement
Also called synovial joints
Subdivided by type of motion
Copyright © 2010 Pearson Education, Inc.
Classification of Joints
Copyright © 2010 Pearson Education, Inc.
Classification of Joints
Copyright © 2010 Pearson Education, Inc.
Classification of Joints
Structural Classifications
Bony
Fibrous
Cartilaginous
Synovial
Copyright © 2010 Pearson Education, Inc.
Classification of Joints
Copyright © 2010 Pearson Education, Inc.
Classification of Joints
Functional Classifications Synarthroses (immovable joints)
Are very strong
Edges of bones may touch or interlock
Four types of synarthrotic joints:
– suture
– gomphosis
– synchondrosis
– synostosis
Copyright © 2010 Pearson Education, Inc.
Classification of Joints
Synarthrotic Joints
Suture
Bones interlocked
Are bound by dense fibrous connective tissue
Are found only in skull
Gomphosis
Fibrous connection (periodontal ligament)
Binds teeth to sockets
Copyright © 2010 Pearson Education, Inc.
Classification of Joints
Synarthrotic Joints Synchondrosis
Is a rigid cartilaginous bridge between two bones:– epiphyseal cartilage of long bones
– between vertebrosternal ribs and sternum
Synostosis Fused bones, immovable:
– metopic suture of skull
– epiphyseal lines of long bones
Copyright © 2010 Pearson Education, Inc.
Classification of Joints
Functional Classifications
Amphiarthroses
More movable than synarthrosis
Stronger than freely movable joint
Two types of amphiarthroses
– syndesmosis:
» bones connected by ligaments
– symphysis:
» bones separated by fibrous cartilage
Copyright © 2010 Pearson Education, Inc.
Classification of Joints
Functional Classifications
Synovial joints (diarthroses)
Also called movable joints
At ends of long bones
Within articular capsules
Lined with synovial membrane
Copyright © 2010 Pearson Education, Inc.
Synovial Joints
Components of Synovial Joints
Articular cartilages
Pad articulating surfaces within articular
capsules:
– prevent bones from touching
Smooth surfaces lubricated by synovial fluid:
– reduce friction
Copyright © 2010 Pearson Education, Inc.
Synovial Joints
Components of Synovial Joints
Synovial fluid
Contains slippery proteoglycans secreted by fibroblasts
Functions of synovial fluid:
– lubrication
– nutrient distribution
– shock absorption
Copyright © 2010 Pearson Education, Inc.
Synovial Joints Components of Synovial Joints
Accessory structures Cartilages:
– cushion the joint:
» Fibrous cartilage pad called a meniscus (articular disc)
Fat pads:
– superficial to the joint capsule
– protect articular cartilages Ligaments:
– support, strengthen joints
– sprain: ligaments with torn collagen fibers
Copyright © 2010 Pearson Education, Inc.
Synovial Joints
Components of Synovial Joints
Accessory structures
Tendons:
– attach to muscles around joint
– help support joint
Bursae:
– pockets of synovial fluid
– cushion areas where tendons or ligaments rub
Copyright © 2010 Pearson Education, Inc.
Synovial Joints
Factors That Stabilize Synovial Joints
Prevent injury by limiting range of motion
Collagen fibers (joint capsule, ligaments)
Articulating surfaces and menisci
Other bones, muscles, or fat pads
Tendons of articulating bones
Copyright © 2010 Pearson Education, Inc.
Synovial Joints
Figure 8–1a The Structure of a Synovial Joint.
Copyright © 2010 Pearson Education, Inc.
Synovial Joints
Figure 8–1b The Structure of a Synovial Joint.
Copyright © 2010 Pearson Education, Inc.
Synovial Joints
Injuries
Dislocation (luxation)
Articulating surfaces forced out of position
Damages articular cartilage, ligaments, joint capsule
Subluxation
A partial dislocation
Copyright © 2010 Pearson Education, Inc.
Movements
Types of Dynamic Motion
Linear motion (gliding)
Angular motion
Rotation
Planes (Axes) of Dynamic Motion
Monaxial (1 axis)
Biaxial (2 axes)
Triaxial (3 axes)
Copyright © 2010 Pearson Education, Inc.
Movements
Figure 8–2 A Simple Model of Articular Motion.
Copyright © 2010 Pearson Education, Inc.
Movements
Figure 8–2 A Simple Model of Articular Motion.
Copyright © 2010 Pearson Education, Inc.
Movements
Types of Movements at Synovial Joints
Terms describe
Plane or direction of motion
Relationship between structures
Copyright © 2010 Pearson Education, Inc.
Movements
Types of Movements at Synovial Joints
Linear motion
Also called gliding
Two surfaces slide past each other:
– between carpal or tarsal bones
Copyright © 2010 Pearson Education, Inc.
Movements
Angular Motion Flexion
Angular motion
Anterior–posterior plane
Reduces angle between elements
Extension Angular motion
Anterior–posterior plane
Increases angle between elements
Copyright © 2010 Pearson Education, Inc.
Movements
Angular Motion
Hyperextension
Angular motion
Extension past anatomical position
Angular Movements
Copyright © 2010 Pearson Education, Inc.
Movements
Figure 8–3a Angular Movements.
Copyright © 2010 Pearson Education, Inc.
Movements
Angular Motion Abduction
Angular motion
Frontal plane
Moves away from longitudinal axis
Adduction Angular motion
Frontal plane
Moves toward longitudinal axis
Copyright © 2010 Pearson Education, Inc.
Movements
Figure 8–3 Angular Movements.
Copyright © 2010 Pearson Education, Inc.
Movements
Figure 8–3 Angular Movements.
Copyright © 2010 Pearson Education, Inc.
Movements
Angular Motion
Circumduction
Circular motion without rotation
Angular motion
Copyright © 2010 Pearson Education, Inc.
Movements
Figure 8–3 Angular Movements.
Copyright © 2010 Pearson Education, Inc.
Movements
Types of Movement at Synovial Joints
Rotation Direction of rotation from anatomical position
Relative to longitudinal axis of body
Left or right rotation
Medial rotation (inward rotation):
– rotates toward axis
Lateral rotation (outward rotation):
– rotates away from axis
Copyright © 2010 Pearson Education, Inc.
Movements
Figure 8–4a Rotational Movements.
Copyright © 2010 Pearson Education, Inc.
Movements
Types of Movements at Synovial Joints
Rotation
Pronation:
– rotates forearm, radius over ulna
Supination:
– forearm in anatomical position
Copyright © 2010 Pearson Education, Inc.
Movements
Figure 8–4b Rotational Movements.
Copyright © 2010 Pearson Education, Inc.
Movements
Types of Movements at Synovial Joints Special movements
Inversion:
– twists sole of foot medially
Eversion:
– twists sole of foot laterally
Dorsiflexion:
– flexion at ankle (lifting toes)
Plantar flexion:
– extension at ankle (pointing toes)
Copyright © 2010 Pearson Education, Inc.
Movements
Special Movements at Synovial Joints Opposition
Thumb movement toward fingers or palm
(grasping)
Protraction Moves anteriorly
In the horizontal plane (pushing forward)
Retraction Opposite of protraction
Moving anteriorly (pulling back)
Copyright © 2010 Pearson Education, Inc.
Movements
Special Movements at Synovial Joints
Elevation Moves in superior direction (up)
Depression Moves in inferior direction (down)
Lateral flexion Bends vertebral column from side to side
Copyright © 2010 Pearson Education, Inc.
Movements
Figure 8–5 Special Movements.
Copyright © 2010 Pearson Education, Inc.
Movements
Figure 8–5 Special Movements.
Copyright © 2010 Pearson Education, Inc.
Movements
Classification of Synovial Joints by Shape Gliding Hinge Pivot Ellipsoid Saddle Ball-and-socket
A Functional Classification of Synovial Joints
Copyright © 2010 Pearson Education, Inc.
Movements
Gliding Joints
Flattened or slightly curved faces
Limited motion (nonaxial)
Hinge Joints
Angular motion in a single plane (monaxial)
Pivot Joints
Rotation only (monaxial)
Copyright © 2010 Pearson Education, Inc.
Movements
Figure 8–6 Movements at Synovial Joints.
Copyright © 2010 Pearson Education, Inc.
Movements
Ellipsoid Joints Oval articular face within a depression
Motion in two planes (biaxial)
Saddle Joints Two concave, straddled (biaxial)
Ball-and-Socket Joints Round articular face in a depression (triaxial)
Copyright © 2010 Pearson Education, Inc.
Movements
Figure 8–6 Movements at Synovial Joints.
Copyright © 2010 Pearson Education, Inc.
Movements
A joint cannot be both mobile and strong
The greater the mobility, the weaker the
joint
Mobile joints are supported by muscles
and ligaments, not bone-to-bone
connections
Copyright © 2010 Pearson Education, Inc.
Intervertebral Articulations
Intervertebral Articulations
C2 to L5 spinal vertebrae articulate
At inferior and superior articular processes (gliding
joints)
Between adjacent vertebral bodies (symphyseal
joints)
Copyright © 2010 Pearson Education, Inc.
Intervertebral Articulations
Intervertebral Articulations C2 to L5 spinal vertebrae articulate
Intervertebral discs:– pads of fibrous cartilage
– separate vertebral bodies
– anulus fibrosus:
» tough outer layer
» attaches disc to vertebrae
– nucleus pulposus:
» elastic, gelatinous core
» absorbs shocks
Copyright © 2010 Pearson Education, Inc.
Intervertebral Articulations
Figure 8–7 Intervertebral Articulations.
Copyright © 2010 Pearson Education, Inc.
Intervertebral Articulations
Vertebral Joints
Also called symphyseal joints
As vertebral column moves
Nucleus pulposus shifts
Disc shape conforms to motion
Intervertebral Ligaments
Bind vertebrae together
Stabilize the vertebral column
Copyright © 2010 Pearson Education, Inc.
Intervertebral Articulations
Six Intervertebral Ligaments
Anterior longitudinal ligament
Connects anterior bodies
Posterior longitudinal ligament
Connects posterior bodies
Ligamentum flavum
Connects laminae
Copyright © 2010 Pearson Education, Inc.
Intervertebral Articulations
Six Intervertebral Ligaments
Interspinous ligament
Connects spinous processes
Supraspinous ligament
Connects tips of spinous processes (C7 to sacrum)
Ligamentum nuchae
Continues supraspinous ligament (C7 to skull)
Copyright © 2010 Pearson Education, Inc.
Intervertebral Articulations
Damage to Intervertebral Discs
Slipped disc
Bulge in anulus fibrosus
Invades vertebral canal
Herniated disc
Nucleus pulposus breaks through anulus fibrosus
Presses on spinal cord or nerves
Copyright © 2010 Pearson Education, Inc.
Intervertebral Articulations
Movements of the Vertebral Column Flexion
Bends anteriorly
Extension Bends posteriorly
Lateral flexion Bends laterally
Rotation Turning
Copyright © 2010 Pearson Education, Inc.
Articulations of the Axial Skeleton
Copyright © 2010 Pearson Education, Inc.
Articulations of the Axial Skeleton
Copyright © 2010 Pearson Education, Inc.
Articulations of the Axial Skeleton
Copyright © 2010 Pearson Education, Inc.
The Shoulder Joint
Also called the glenohumeral joint
Allows more motion than any other joint
Is the least stable
Supported by skeletal muscles, tendons, ligaments
Ball-and-socket diarthrosis
Between head of humerus and glenoid cavity of
scapula
Copyright © 2010 Pearson Education, Inc.
The Shoulder Joint
Socket of the Shoulder Joint
Glenoid labrum
Deepens socket of glenoid cavity
Fibrous cartilage lining
Extends past the bone
Processes of the Shoulder Joint
Acromion (clavicle) and coracoid process (scapula)
Project laterally, superior to the humerus
Help stabilize the joint
Copyright © 2010 Pearson Education, Inc.
The Shoulder Joint
Shoulder Ligaments
Glenohumeral
Coracohumeral
Coraco-acromial
Coracoclavicular
Acromioclavicular
Shoulder Separation
Dislocation of the shoulder joint
Copyright © 2010 Pearson Education, Inc.
The Shoulder Joint
Shoulder Muscles (also called rotator cuff) Supraspinatus Infraspinatus Subscapularis Teres minor
Shoulder Bursae Subacromial Subcoracoid Subdeltoid Subscapular
Copyright © 2010 Pearson Education, Inc.
The Shoulder Joint
Figure 8–8a The Shoulder Joint.
Copyright © 2010 Pearson Education, Inc.
The Shoulder Joint
Figure 8–8b The Shoulder Joint.
Copyright © 2010 Pearson Education, Inc.
The Elbow Joint
A stable hinge joint
With articulations involving humerus,
radius, and ulna
Copyright © 2010 Pearson Education, Inc.
The Elbow Joint
Articulations of the Elbow
Humero-ulnar joint
Largest articulation
Trochlea of humerus and trochlear notch of ulna
Limited movement
Humeroradial joint:
Smaller articulation
Capitulum of humerus and head of radius
Copyright © 2010 Pearson Education, Inc.
The Elbow Joint
Figure 8–9a The Elbow Joint.
Copyright © 2010 Pearson Education, Inc.
The Elbow Joint
Supporting Structures of the Elbow Biceps brachii muscle
Attached to radial tuberosity
Controls elbow motion
Elbow Ligaments Radial collateral
Annular
Ulnar collateral
Copyright © 2010 Pearson Education, Inc.
The Elbow Joint
Figure 8–9b The Elbow Joint.
Copyright © 2010 Pearson Education, Inc.
The Hip Joint
Also called coxal joint
Strong ball-and-socket diarthrosis
Wide range of motion
Copyright © 2010 Pearson Education, Inc.
The Hip Joint
Structures of the Hip Joint Head of femur fits into it
Socket of acetabulum
Which is extended by fibrocartilaginous acetabular labrum
Ligaments of the Hip Joint Iliofemoral
Pubofemoral
Ischiofemoral
Transverse acetabular
Ligamentum teres
Copyright © 2010 Pearson Education, Inc.
The Hip Joint
Figure 8–10a The Hip Joint.
Copyright © 2010 Pearson Education, Inc.
The Hip Joint
Figure 8–10b The Hip Joint.
Copyright © 2010 Pearson Education, Inc.
The Hip Joint
Figure 8–10c The Hip Joint.
Copyright © 2010 Pearson Education, Inc.
The Knee Joint
A complicated hinge joint
Transfers weight from femur to tibia
Articulations of the knee joint
Two femur–tibia articulations
At medial and lateral condyles
One between patella and patellar surface of femur
Copyright © 2010 Pearson Education, Inc.
The Knee Joint
Menisci of the Knee Medial and lateral menisci
Fibrous cartilage pads
At femur–tibia articulations
Cushion and stabilize joint
Give lateral support
Locking knees Standing with legs straight:
– “locks” knees by jamming lateral meniscus between tibia and femur
Copyright © 2010 Pearson Education, Inc.
The Knee Joint
Seven Ligaments of the Knee Joint
Patellar ligament (anterior)
Two popliteal ligaments (posterior)
Anterior and posterior cruciate ligaments (inside joint
capsule)
Tibial collateral ligament (medial)
Fibular collateral ligament (lateral)
Copyright © 2010 Pearson Education, Inc.
The Knee Joint
Figure 8–11a The Knee Joint.
Copyright © 2010 Pearson Education, Inc.
The Knee Joint
Figure 8–11b The Knee Joint.
Copyright © 2010 Pearson Education, Inc.
The Knee Joint
Figure 8–11c The Knee Joint.
Copyright © 2010 Pearson Education, Inc.
The Knee Joint
Figure 8–11d The Knee Joint.
Copyright © 2010 Pearson Education, Inc.
The Knee Joint
Copyright © 2010 Pearson Education, Inc.
The Knee Joint