HUMAN ANATOMY
Chapter 1 Lecture
ArticulationsThe Skeletal System: Articulations
Articulations
Introduction
• Joints, or articulations, are connections between bones that may or may not permit movement.– Cartilage, fluid, or dense
connective tissues is usually involved in holding joints together.
• Joints maybe classified structurally or functionally
Classification of Articulations - StructuralStructural Classification1) Fibrous – No joint cavity – fibrous tissue
a) Suture – very thin fibrous tissueif fused – synostoses
b) Syndesmosis – broader fibrous tissuefontanel
c) Gomphosis – peg in coneexample: tooth in jaw
2) Cartilaginous – No joint cavity – Cartilagea) Synchondrosis – hyaline cartilage
epiphyseal plateb) Symphysis – fibrocartilage
symphysis pubis and intervertebral disks
3) Synovial – Joint (Synovial) cavitya) Gliding – intertarsalb) Hinge – knee and anklec) Pivot – atlantoaxiald) Condyloid or Ellipsoidal – wriste) Saddle – thumbf) Ball and Socket – should and hip
Classification of Articulations FunctionalFunctional Classification of Joint
1) Synarthroses – Immovable Jointsa) Sutureb) Gompohsisc) Synchondrosis
2) Amphiarthrosis – Slightly movable jointsa) Symphysis – pubic symphysisb) Syndesmosis - tibia and fibula
3) Diarthrosis – Freely movablea) Gliding – glidingb) Hinge – flex and extend (1 plane)c) Pivot – rotation – 1 planed) Condyloid or Ellipsoidal – 2 planes
flex, extend, abduct and adducte) Saddle – – 2 planes
flex, extend, abduct and adductf) Ball and Socket – (3 planes)
flex, extend; abduct adduct; and medial and lateral rotation
Synarthroses (Immovable Joints)
• Sutures are joints found only in the skull.– Bony edges interlock and short dense connective
tissue fiber hold the bones together.
• A gomphosis is the joint between a tooth and the alveolar fossa of the maxillae or mandible.– Periodontal ligaments (PDL) hold the tooth to the
bone in the gomphosis.
• A synchondrosis is a joint in which hyaline cartilage separates the ends of the bones involved in the joint.
• A synostosis occurs if bones fuse together to form one bone.
Amphiarthroses (Slightly Movable Joints)
• A syndesmosis occurs when to bones are connected by relatively long connective tissue ligaments.
• Connecting bones using a fibrocartilage pad forms a symphysis.
Diarthroses (Freely Movable Joints)
• Synovial joints are typically found at the ends of long bones in the upper and lower limbs.
• All synovial joints have six basic characteristics:– A joint capsule– Articular cartilages– A joint cavity filled with
synovial fluid– A synovial membrane lining
the joint capsule
Figure 8.1 Structure of a Synovial Joint
Synovial Joints
Synovial Fluid
• Synovial fluid has three functions:– Lubricates the surfaces of the articular
cartilages on the ends of the bones.– Nourishes the chondrocytes by entering and
exiting the articular cartilages due to the forces acting on the joint.
– Acts as a shock absorber.
PLAY
Movements
Types of Movements
• Angular movements• Rotation
Special Movements
• Movements at the ankle include:– Eversion/inversion– Dorsiflexion/plantar flexion
• Movement of the vertebral column includes:– Lateral flexion
• Movement of the pollex (thumb):– Opposition/reposition
Special Movements
• Movements that occur at many joints include:– Protraction: anterior movement in the
horizontal plane – Retraction: posterior movement in the
horizontal plane– Elevation: cranial movement in the vertical
axis– Depression: caudal movement in the vertical
axis
PLAY Joint Structure
Structural Classification of Synovial Joints
• Plane joints: – Nonaxial or multiaxial
• Hinge joints: – flexion and extension
• Pivot joints: – rotational movements
Structural Classification of Synovial Joints
• Condylar joints:– flexion/extension and abduction/adduction
• Saddle joints:– biaxial joints that also allow circumduction
• Ball and socket joints: – triaxial joints
Figure 8.7a,b The Temporomandibular Joint (TMJ)
The Temporomandibular Joint
Figure 8.8a Anterior Vertebral Column Figure 8.8b Lateral Vertebral Column
Intervertebral Articulations
Vertebral Movements
• There are four possible movements of the vertebral column:– Anterior flexion, or bending forward– Extension, or bending backward– Lateral flexion, or bending to the side– Rotation–twisting
Figure 8.10 The Sternoclavicular Joint
The Sternoclavicular Joint
Figure 8.11a The Anterior Shoulder Figure 8.11b The Lateral Shoulder
The Shoulder Joint
Figure 8.11c Sectional Shoulder Figure 8.11d Superior Shoulder
The Shoulder Joint
Figure 8.12a Medial Elbow Figure 8.12d Longitudinal Elbow
The Elbow Joint
Figure 8.13b Wrist Joints Figure 8.13c Wrist Ligaments
The Wrist
Figure 8.13d Joints of the Hand
The Joints of the Hand
Figure 8.14a Lateral Hip Figure 8.14c Posterior Hip
The Hip Joint
Figure 8.14b Anterior Hip Figure 8.15a Sectional Hip
The Hip Joint
Figure 8.16a Anterior Knee Figure 8.16b Parasagittal Knee
The Knee
Figure 8.17a Posterior Superficial Figure 8.17b Posterior Deep
The Knee
Figure 8.17c Anterior Knee
The Knee
Figure 8.18a Ankle and Foot Figure 8.18b Ankle and Foot MRI
The Ankle and Foot