JOINTS
Learning Objectives
• To know the different joint
types
• To understand how to
classify joint types
• To be able to discuss the
importance of the structure
and function of a synovial
joint
Joints

The human skeleton is jointed to
allow movement.

Muscular contraction causes the
bones to move about the joints.
A joint is where two or more bones meet
and
muscles act together to cause movement.
Types of Joints
There are 3 main types of joint found in the body.
1. Fibrous/ immovable joints
The bones at an immoveable joint cannot move - they
overlap or interlock, and are held together by a tough
fibre, e.g.
the skull.
2. Cartilaginous/slightly moveable joints
The bones at a slightly moveable joint can only move
a little - they are held together by strong straps
called ligaments and are joined by protective pads
known as cartilage, e.g.
the ribs.
3. Synovial joint/freely moveable
At a freely moveable joint the bones move freely.
They are also known as synovial joints, and
are the largest group of joints found in the body,
e.g.
the hips, shoulders and knees.
Freely Moveable Joints
 Freely Moveable joints are also known as Synovial Joints.
 They are freely moving and occur where 2 or more bones
meet.
 There are about 70 freely moveable joints in the human
skeleton.
 These interest us the most because they allow the
greatest range of movement and are found in the
appendicualr skeleton
Cartilage
1. Hyaline or Articular cartilage- found on the surface
of bone
2. Yellow Elastic cartilage- elastic and found in the
external ear
3. White Fibrocartilage- tough, dense tissue that
acts as a shock absorber. Found between the vertebrae
1. Articular/hyaline Cartilage – A material which
covers the end of each bone, and which helps
prevent friction between the joint.
•
Absorbs compression placed on the joint,
protects the joint.
2. Joint Capsule – The outer layer is a tough
fibrous layer called the fibrous capsule.
• Increases stability
• The inner layer is called the synovial membrane
• Secretes synovial fluid, strengthens the joint
3. Synovial Membrane– Thin membrane which
lines the inside of the joint capsule.
•
It produces synovial fluid
4. Synovial Fluid – The fluid which surrounds
the joint and is contained in the joint cavity.
•
•
•
Reduce friction between the cartilage
Nourish the cartilage
Get rid of any waste debris
4. Ligaments – A band of strong fibrous tissue, helps
prevent dislocation.
• Connect bone to bone
5. Tendons– Strong connective tissue that attached muscle
to bone.
• Connect muscle to muscle
6. Bursa- pad of fat provide cushioning between the fibrous
capsule and a bone or muscle.
• Cushion the joint and act as shock absorbers
The Synovial Joint of the Knee
The knee is a hinge joint.
Articular(hyaline)Cartilage
Joint capsule
Synovial Membrane
Patella
Femur
Cruciate Ligaments
Synovial Fluid
Joint
cavity
Tendons
Tibia/Fibula
The Synovial Joint of the Hip
The Hip is a ball and socket joint.
Cartilage
Pelvis
Synovial
Membrane
Synovial Fluid
Ligaments
Tendons
Femur
TASK
1. Label the diagram of a synovial joint
using a colour code system
YOU MAY BE ASKED TO LABEL A SYNOVIAL JOINT IN
EXAM OR EXPLAIN THE STRUCTURE AND FUCTION
2. List two features that increase joint
stability and give their specific
function?
Examples of Synovial Joints
Types of Synovial Joints
Synovial joints are classifed according to the shape of the
articulating surface.
KEY
Ball & Socket Joint
Hinge Joint
Pivot Joint
Gliding Joint
Saddle Joint
Condyloid Joint
KEY TERM
ARTICULATION-
The different bones that form to make the joint
EXAMPLE
Joint
Joint type
Movement
Elbow
Hinge joint
Articulating bones
Humerus, radius, ulna
Write down another example
1. Ball and Socket Joints
The ball has a head shaped of one bone which articulates
with a cuplike socket.
Allows the greatest range of movement
Examples
HIP
SHOULDER
2. Hinge Joints
They are cylindrical shaped of 1 bone articulates with
a depression of an adjacent bone
Movement is restricted to bending and straightening
EXAMPLES
ELBOW
KNEE
3. Pivot Joints
These are rounded, pointed or concave of one bone
which articulates which a ring shaped bone.
Movement is restricted to 1 bone rotating around
the longitudinal axis.
EXAMPLE
VERTEBRAE OF
THE NECK
4. Gliding Joints
The articulating surfaces are flat.
It allows limited movement
EXAMPLES
HAND BETWEEN THE CARPELS
5. Saddle Joints
The articulating surfaces are shaped like a saddle
It allows very limited movement
EXAMPLE
THUMB JOINT
6. Condyloid Joints
The surfaces are flatter and oval forming a shallow joint
It allows the second greatest range of movement.
EXAMPLE
WRIST JOINT
Structure and function
Hyaline/Articular cartilage
Structure: Smooth, spongy cartilage that covers end
of bone.
Function: prevent friction between bones
absorb compression placed on the joint
protect bone from getting crushed
Joint capsule:
Structure: Outer layer is a tough fibrous layerfibrous membrane.
The inner layer- synovial membrane
Function:strengthen the joint
secrete synovial fluid
Synovial Fluid
Structure; slippery fluid, contained in the joint cavity
Function; reduce friction between cartilage
nourish the articular cartilage
get rid of waste debris in joint
Ligament
Structure; band of strong fibrous tissue
Function; connect bone to bone
Meniscus (cartilage)
Structure: white fibrocartilage
Function: improves the fit between bone ends
increases joint stability
reduces wear and tear at joint
Bursa
Structure:fluid filled sacs
Function: prevent friction where bones, ligaments
and muscles may rub together
PLENARY
Identify the bones that articulate at the
shoulder joint? (2 marks)
Identify the bones that articulate at the
elbow joint? (3 marks)
Ball and Socket Joints
The ball has a head shaped of
one bone which articulates
with a cuplike socket.
Allows the greatest range of
movement
Hinge Joints
They are cylindrical shaped of
1 bone articulates with
a depression of an adjacent
bone
Movement is restricted to
bending and straightening
Examples
HIP
SHOULDER
EXAMPLES
ELBOW
KNEE
Pivot Joints
These are rounded, pointed or
concave of one bone which
articulates which a ring shaped
bone.
Movement is restricted to 1 bone
rotating around the longitudinal
axis.
Gliding Joints
The articulating surfaces are flat.
It allows limited movement
VERTEBRAE OF
THE NECK
HAND
BETWEEN THE
CARPELS
Saddle Joints
The articulating surfaces are
shaped like a saddle
EXAMPLE
THUMB JOINT
It allows very limited movement
Condyloid Joints
The surfaces are flatter
and oval forming a shallow
joint
It allows the second
greatest range of
movement.
EXAMPLE
WRIST JOINT