8.5: Types of Synovial Joints

Learning Outcomes

  1. Describe the anatomical features of each structural type of synovial joint

  2. Describe where each structural type can be found

  3. Predict the kinds of movements that each structural type of synovial joint will allow

Types of Synovial Joints

Synovial joints are characterized by a fluid-filled joint capsule, allowing for varied movements and providing stability through ligaments, tendons, and surrounding muscles. Synovial joints are classified into several types based on their anatomy and the movements they enable. Below is a detailed description of each type:

A. Plane Joint (Gliding Joint)

  1. Description:

    • The plane joint is the simplest type of joint, consisting of flat or slightly curved articulating surfaces of two bones.

    • This type of joint facilitates gliding or sliding movements.

  2. Location:

    • Found in locations such as the intercarpal joints of the wrists and the intertarsal joints of the ankles.

  3. Movement:

    • Permits limited motion in one plane, mainly allowing for gliding actions when bones slide past each other; allows for waving

B. Hinge Joint

  1. Description:

    • In a hinge joint, one bone has a convex articular surface that fits into the concave depression of another bone.

    • It is structured to allow motion similar to that of a door hinge.

  2. Location:

    • Commonly found in the elbow (humeroulnar joint) and knee joints.

  3. Movement:

    • Allows uniaxial movement, enabling flexion and extension along one axis only.

C. Pivot Joint

  1. Description:

    • This joint features a rounded end surface of one bone that fits into a trough of another bone, allowing for rotation around a single axis.

  2. Location:

    • An example is the atlantoaxial joint between the first and second cervical vertebrae, which allows for head rotation.

  3. Movement:

    • Enables uniaxial rotational movement, allowing one bone to pivot around another.

D. Condylar or Ellipsoid Joint

  1. Description:

    • Characterized by an oval-shaped convex surface of one bone fitting into a matching concave surface of another.

  2. Location:

    • Found in joints such as the metacarpophalangeal joints of the fingers (knuckles).

  3. Movement:

    • Allows for biaxial movement, permitting flexion, extension, abduction, and adduction in two planes.

E. Saddle Joint

  1. Description:

    • Each bone in a saddle joint has both a concave and a convex surface that resemble a saddle shape.

    • This configuration allows for enhanced movement.

  2. Location:

    • A notable example is the carpometacarpal joint of the thumb.

  3. Movement:

    • Allows biaxial movement, including flexion, extension, abduction, adduction, and circumduction, providing a wide range of motion.

F. Ball-and-Socket Joint

  1. Description:

    • In this joint, a spherical articulating surface of one bone fits into a cup-shaped depression of another bone, enabling a versatile range of movement.

  2. Location:

    • The shoulder (glenohumeral joint) and hip (acetabulofemoral joint) are prime examples.

  3. Movement:

    • Allows for multiaxial movement in all directions—flexion, extension, rotation, and circumduction, utilizing all three axes available for joint movement.

Types of Synovial Joints