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NOTES part 5 : Joints and
Types of Movements
(Ch 7)
*Joints are functional junctions
between bones.
• Functions of Joints
– They hold the skeletal bones together
– Allow the rigid skeleton some flexibility so that
gross movements can occur.
TYPES OF JOINTS
•
Joints are classified by structure & by
function
– Functional classification is based on the
amount of movement allowed at the joint
1. Synarthroses
2. Amphiarthroses
3. Diarthroses
– Structural classification focuses on the
material binding the bones together
1. Fibrous
2. Cartilaginous
3. Synovial
FUNCTIONAL TYPES OF JOINTS
1. Synarthroses: immovable joints
2. Amphiarthroses: slightly movable
3. Diarthroses: freely movable
STRUCTURAL TYPES OF JOINTS
**These joints can be classified according to
the type of tissue that binds the bones
together.**
 FIBROUS JOINTS
(Synarthroses):
• Bones at fibrous joints are tightly joined by a
layer of dense connective tissue.
•Little or no movement occurs at a fibrous
joint
• Example: the sutures between the flat bones
of the skull
• 3 types of fibrous joints
– 1) Syndesmoses- fibrous bands connect 2 bones
(radius and ulna)
– 2) Sutures- teethlike projections from adjacent
bones fit together with a thin layer of fibrous tissue
between them.
• Becomes fully ossified in older adults
• only found in the skull
– 3) Gomphoses- joint that occurs between the root
of a tooth and the alveolar process
• Periodontal membrane- fibrous tissue between tooth’s
root and alveolar process
FYI
 CARTILAGINOUS JOINTS
(Amphiarthroses):
• A layer of hyaline cartilage, or fibrocartilage,
joins bones of cartilaginous joints
• Allow limited movement
• Example: the joints that separate the
vertebrae
• 2 types of cartilaginous joints
– 1) Synchondroses- have hyaline cartilage
between the articulating bones
• Articulation between first rib and sternum
• Epiphyseal plate present during growth
– 2) Sympheses- fibrocartilage disks between
articulating bones
• Fibrocartilage disk will only allow slight movement
when pressure is applied to bones
• Found in vertebral column and symphysis pubis
 SYNOVIAL JOINTS:
• Most joints in the body are
synovial joints
• Allow free movement
• Synovial joints have 7
characteristic structures
• Bones at synovial joints are
covered with hyaline cartilage
(“articular cartilage”) and held
together by a fibrous
JOINT CAPSULE.
 SYNOVIAL JOINTS:
• The joint capsule consists of an outer layer of
ligaments and an inner lining of synovial
membrane (which secretes synovial fluid
to lubricate the joint).
• Some synovial joints have flattened, shockabsorbing pads of fibrocartilage called
MENISCI between the articulating surfaces
of the bones
 SYNOVIAL JOINTS:
• Some synovial joints may also have
BURSAE, which are fluid-filled sacs located
between the skin and the underlying bony
prominences.
• Example: at the knee joint, the patella is
sandwiched between 2 bursae.
 SYNOVIAL JOINTS:
• Most synovial joints also have ligaments, which are
strong cords of dense, white fibrous connective tissue
which grow between bones and bind them together
(makes the joint more stable than with a joint capsule
alone)
• Ex. Knee joint
– Anterior Cruciate Ligament (ACL) - attaches anterior
part of tibia to posterior part of lateral condyle of the
femur
– Posterior Cruciate Ligament (PCL) - attaches
posterior part of tibia and lateral meniscus to the
femur’s medial condyle
– Medial Collateral Ligament (MCL)- located on the
medial side of the knee
– Lateral Collateral Ligament (LCL)- located on the
lateral side of the knee
TYPES OF SYNOVIAL JOINTS:
• Ball-and-socket:
Head of 1 bone articulates
with cuplike socket of
another (shoulder, hip)
• Condyloid
(Ellipsoidal): oval
articular surface of 1 bone
fits into a concavity in
another (occipital condyle
and atlas)
• Gliding: allow only short
slipping or gliding movements
(carpals, tarsals)
TYPES OF SYNOVIAL JOINTS:
• Hinge:
cylindrical
projection of 1
bone fits into a
trough-shaped
surface of another
(knee, elbow)
• Pivot: rounded
end of 1 bone
protrudes into a
ring of bone of
another (ex: atlas
& dens of axis)
• Saddle:
resemble
condyloid joints
but allow greater
freedom of
movement
(thumb)
MOVEMENTS ALLOWED BY
SYNOVIAL JOINTS
• Muscles fastened on either side of a joint
produce movements of synovial joints.
• Typically, one end of a muscle is attached to a
relatively immovable or fixed part on one side
of a joint, and the other end of the muscle is
fastened to a movable part on the other side
 SYNOVIAL JOINT MOVEMENTS
INCLUDE…
• Flexion
• Extension
• Dorsiflexion
• Plantar flexion
•Hyperextension
 JOINT MOVEMENTS (cont.)
• Abduction
• Adduction
• Rotation
• Circumduction
 JOINT MOVEMENTS (cont.)
• Pronation
• Supination
• Eversion
• Inversion
 JOINT MOVEMENTS (cont.)
• Retraction
• Protraction
• Elevation
• Depression