THE CLASSIFICATION OF JOINTS 109 



The Classification of Joints. All joints of the body 

 are classified under three main groups immovable 

 articulation (synarthrosis), slightly movable or mixed 

 articulation (amphiarthros), movable articulation (diar- 

 throsis). 



FIG. 52 



Occipito-axial and atlanto-axial ligaments. Posterior view, obtained by 

 removing the arches of the vertebrae and the posterior part of the skull. 

 (Gray.) 



Synarthrosis or Immovable Joint. Under this classi- 

 fication are included all the articulations in which 

 the surfaces of the bones are in almost direct contact, 

 being fastened together by an intervening mass of 

 connective tissue, and in which there is no joint cavity 

 and scarcely any motion. Examples: joints between 

 the bones of the skull and face, excepting those of the 

 mandible. 



Amphiarthros or Mixed Joint. In this variety there 

 is only a slight amount of motion. There are two 

 varieties symphysis, as the symphysis pubes and 



