JOINTS
And I’m
not talking
about the
illegal
kind.
JOINTS
Joints (articulations) hold bones together giving
stability & mobility.
Classified according to the degree of movement:
 Immovable – Fibrous joints
 Slightly movable – Cartilaginous joints
 Freely movable – Synovial joints
7-2
IMMOVABLE JOINTS
 Fibrous joints
 Bones are held together by collagenous fibers
 Are collagenous fibers stretchy or strong?
 No joint cavity
 Example: Skull sutures, tibiofibular joints
SLIGHTLY MOVABLE
 Cartilaginous joints
 Bones are held together by cartilage
 No joint cavity
 Example: costosternal joints, pubic symphysis,
intervertebral discs
FREELY MOVABLE JOINTS
 Synovial Joints
 Most common type of joint in the body
 The bones that articulate are separated by a joint cavity that is
filled with synovial fluid and joined together by ligaments
 Allows for more movement
 Examples:
 Shoulder
 Hip
 Elbow
 Knee
 Carpal
 Interphalangeal joints
SYNOVIAL JOINTS
 Structures in a synovial joint
 Articulating cartilage
 Joint capsule
 Synovial membrane
 Joint cavity
 Bursae
 Meniscus
SYNOVIAL JOINTS
 Structure of a synovial joint
 Articulating Cartilage –
hyaline cartilage on the ends
of articulating bones
 Joint Capsule – layer of dense
connective tissue that joins
with the periosteum
SYNOVIAL JOINTS
 Structure of a synovial joint
 Synovial Membrane – inner
layer of joint capsule,
secretes synovial fluid
 Joint Cavity – lubricates
articulating surfaces within
joints, has the consistency of
egg whites
SYNOVIAL JOINTS
 Structure of a synovial joint
 Bursae – fibrous membrane bags filled with synovial fluid
 Often found where bones, muscles, tendons, or ligaments
rub together
SYNOVIAL JOINTS
 Structure of a synovial joint
 Meniscus – fibrous cartilage
pads found between the
bones that act as shock
absorbers and stabilize the
joint
 Found in the knee, jaw,
sternoclavicular joints
MENISCAL TEAR
SYNOVIAL JOINTS
 Structure of a synovial joint
 Ligaments – made up of dense connective tissue and
connect bone to bone
T YPES OF SYNOVIAL JOINTS
 Types of synovial joints
 Ball and socket
 Hinge
 Pivot
 Gliding
 Condyloid
 Saddle
T YPES OF SYNOVIAL JOINTS
 Ball and Socket
 Allows for the most movement
 Surface of a rounded head moves in a cup-like cavity of
another bone
 Examples: Shoulder, Hip
T YPES OF SYNOVIAL JOINTS
 Hinge Joint
 Movement resembles a door hinge
 A convex surface of one bone fits into a concave surface
of another
 Examples: Elbow, Knee, and Interphalangeal joints
T YPES OF SYNOVIAL JOINTS
 Pivot Joint
 Bone rotates/pivots on a ring around a central axis
 Examples: Radius on Ulna, Skull on Spine (atlas/axis)
T YPES OF SYNOVIAL JOINTS
 Gliding Joint
 One bone slides from side to side over another bone
 Examples: Carpals and Metacarpals, Tarsals and
Metatarsals
T YPES OF SYNOVIAL JOINTS
 Condyloid Joint
 Oval surface of one bone fits into a complementary
depression on another
 Example: Metacarpal and Proximal Phalanx
T YPES OF SYNOVIAL JOINTS
 Saddle Joint
 Saddle-shaped articular surfaces
 Both bones have a concave and convex articular surface
 Example: Thumb metacarpal - carpal
ACL TEAR