The document provides an overview of joints in clinically oriented anatomy, classifying them into three types: fibrous, cartilaginous, and synovial, with synovial joints being the most common and freely movable. It details the structure and features of these joints, including components like joint capsules, synovial fluid, and types of movements. Additionally, it categorizes six major types of synovial joints based on their shapes and allowed movements.

1. Introduction to Clinically
Oriented Anatomy
‫ــــــ‬ Joints
By: Hasan Arafat

2. Joints are unions between two or more
bones or rigid parts of the skeleton
• They exhibit a variety of forms and
functions
• They are classified according to the
type of the material by which the
articulating bones are united
• They can be also classified according
to mobility

3. Three general types of joints are recognized:
fibrous, cartilaginous and synovial
• These types differ in the manner of
material by which each joint is made
• Freely movable synovial joints are the
most common type
• Most of our movements happen at
synovial joints
• However, the other types perform a
number of very important functions

4. Synovial joints
• In Synovial joints, the articulating are
united by a joint capsule
• The joint capsule is composed of an
outer fibrous layer lined by serous
synovial membrane
• The joint capsule encloses an articular
cavity

5. Synovial joints (continued)
• The joint cavity is a potential space that
contains a small amount of lubricating
synovial fluid
• The lubricating synovial fluid is
secreted by the synovial membrane
that lines the fibrous layer of the joint
capsule

6. Synovial joints (continued)
• Inside the capsule, articular cartilage
covers the articulating surfaces of the
bones
• All other internal surfaces are covered
by synovial membranes
• The periosteum investing the
participating bones external to the joint
blends with the fibrous layer of the
capsule

8. Fibrous joints
• The articulating bones are united b
fibrous tissue
• The amount of movement at this joint
depends on the length of the fibers
uniting the articulating surfaces
• The sutures of the cranium are
examples

10. Fibrous joints (continued)
• Fibrous joints can be subdivided into 2
subtypes
• A syndesmosis type unites the bones
with a sheet of fibrous tissue, either a
ligament or fibrous membrane
• This type is partially movable
• The interosseous membrane between
the radius and ulna is an example

11. Dentatoalveolar syndesmosis: a fibrous joint in
which a peg-like process fits into a socket
articulation between the root of the tooth and the
alveolar process of the jaw
• It’s also called gomphosis or socket
• Mobility at this joint indicates a
pathological state, affecting the
supporting tissue of the tooth
• So, it’s normally immobile
• However, microscopic movements here
is related to proprioception

13. Cartilaginous joints
• They are united by hyaline cartilage or
fibrocartilage
• Can be divided into 2 types
• These types are primary cartilaginous
joints, or synchondroses, and
secondary cartilaginous joints, or
symphyses

14. Cartilaginous joints (continued)
• In synchondroses, the bones are joined
by hyaline cartilage
• Hyaline cartilage permits slight bending
during early life
• Primary cartilaginous joints are usually
temporary unions
• E.g. the growth plate

15. Cartilaginous joints (continued)
• Symphyses are strong, slightly movable
joints
• They are united by fibrocartilage
• E.g. intervertebral discs
• They provide strength and shock
absorption as well as considerable
flexibility to the vertebral column

18. Features of Synovial joints
• They the most common type
• They provide free movement
• They are joints of locomotion
• Typical for limbs joints

19. Features of Synovial joints (cont)
• They are reinforced by accessory
ligaments
• Accessory ligaments are either
separate (extrinsic) or thickening
portions of joint capsule (intrinsic)

20. Features of Synovial joints (cont)
• They also contain fibrocartilaginous
articular discs
• They are also called meniscus
• They are found where articulating
surfaces are incongruous

22. Classification of Synovial joints
• Six major types of synovial joints are
classified according to the shape of
articulating surfaces and the type of
movement they permit
• These types are plane joints, hinge
joints, saddle joints, condyloid joints
and ball-and-socket joints

23. 1. Plane joints
• They are nonaxial
• They permit gliding or sliding
movements in the plane of the articular
surfaces
• The opposed surfaces are flat or almost
flat
• Movement is limited by their tight joint
capsules

24. 1. Plane joints (cont)
• They are numerous and are nearly
always small
• E.g. the acromioclavicular joint

26. 2. Hinge joints
• Permit flexion and extension only
• They are uniaxial
• Movements at these joints happen in
the sagittal plane around a transverse
axis
• Their joint capsules are thin

27. 2. Hinge joints (cont)
• The joint capsule lax anteriorly and
posteriorly where movement occures
• The bones are joined by strong laterally
placed collateral ligaments
• The elbow is an example

30. Saddle joints
• Permit abduction, adduction, flexion
and extension
• Biaxial joints, movements occur in
sagittal and frontal planes
• Circumduction is also available
• E.g. carpometacarpal joint at the thumb

31. Condyloid joints
• Permit flexion, extension, adduction
and abduction
• Biaxial Joints
• The movement at the sagittal is greater
than the frontal
• More restricted circumduction
• E.g. metacarbophalangeal joints

32. Ball and socket joints
• Multiple axes and planes
• Allow flexion, extension, abduction,
adduction, medial and lateral rotation
and circumduction
• Spheroidal surface of one bone moves
within the socket of another
• E.g. hip joint

33. Pivot joints
• Permit rotation around a central axis
• Uniaxial joints
• The rounded process of bone rotates
within a sleeve or ring
• E.g. the median atlantoaxial joint
• The atlas rotates around the dens of
the axis during rotation of the head

35. Synovial joints