Introduction to Sports Biomechanics: Analysing Human Movement ...

THE ANATOMY OF HUMAN MOVEMENT
Figure 6.7 Classification of synovial joints: (a) plane joint; (b) hinge joint; (c) pivot joint; (d) condyloid joint; (e) saddle joint;
(f) ball and socket joint.
some considerable distance from the bone. The former description seems more
useful. Although individual joint movements are small, combinations of several
such joints, as in the carpal region of the hand, can result in significant motion.
Hinge joints are joints in which the concave surface of one bone glides partially
around the convex surface of the other. Examples are the elbow (Figure 6.7(b)) and
ankle joints and the interphalangeal joints of the fingers and toes. The knee is not a
simple hinge joint, although it appears that way when bearing weight. Hinge joints
are uniaxial, permitting only the movements of flexion and extension.
Pivot joints are joints in which one bone rotates about another. This may involve the
bones fitting together at one end, with one rotating about a peg-like pivot in the
other, as in the atlanto-axial joint between the first and second cervical vertebrae.
The class is also used to cover two long bones lying side by side, as in the proximal
radioulnar joint of Figure 6.7(c). These joints are uniaxial, permitting rotation
about the vertical axis in the horizontal plane.
Condyloid joints are classified as biaxial joints, permitting flexion–extension and
abduction–adduction (and, therefore, circumduction). The class is normally used to
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