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1HE ARTICULATIONS, OR JOINTS 



Synarthrosis, or Im- 

 movable Joint. Sur- 

 faces separated by 

 fibrous membrane or 

 by a line of cartilage, 

 without any interven- 

 ing synovial cavity, 

 and immovably con- 

 nected with each 

 other. 



As in joints of cran- 

 ium and face (except 

 mandible). 



A mphiarthrosis, 

 Mixed Articulation. 



Sutura. Articu- 

 lation by processes 

 and indentations 1 

 interlocked. 



Sutura vera (true) 



f Dentata, having tooth- 

 like processes. 



As in interparietal suture. 



Serrata, having serrated 

 edges like the teeth of a 



articulate bv indent- \ 



ed borders. 



Sutura notha 

 (false), articulate by 

 rough surfaces. 



Diarthrosis, 

 Movable Joint. 



As in interfrontal suture. 

 Limbosa, having bevelled 

 margins and dentated pro- 

 cesses. 



As in frontoparietal su- 

 L ture. 



I Squamosa, formed by 

 thin bevelled margins, over- 

 lapping each other. 



As in squamoparietal 

 suture. 



Harmonia, formed by 

 the apposition of contigu- 

 ous rough surfaces. 



As in intermaxillary su- 

 [ ture. 



Schindyksis. Articulation formed by the reception of a thin plate 

 of one bone into a fissure of another. 



As in articulation of rostrum of sphenoid with vomer. 

 Gomphosis. Articulation formed by the insertion of a conical process 

 into a socket the teeth. 



(" Symphysis. Surfaces connected by fibrocartilage. There is a 

 partial joint cavity and may be an incomplete synovial membrane. 

 Has limited motion. As in joints between bodies of vertebrae. 



Syndesmosis. Surfaces united by an interosseous ligament. As in 

 . the inferior tibiofibular articulation. 



f Ginglymus. Hinge-joint; motion limited to two directions, forward 

 and backward. Articular surfaces fitted together so as to permit of 

 movement in one plane. As in the interphalangeal joints and the joint 

 between the humerus and the ulna. 



Trochoid, or Pivot-joint. Articulation by a pivot process turning 

 within a ring or ring around a pivot. As in superior radioulnar articu- 

 lation and atlanto-axial joint. 



Condyloid. Ovoid head received into elliptical cavity. Movements 

 in every direction except axial rotation. As the wrist-joint. 



Reciprocal Reception (saddle-joint). Articular surfaces inversely con- 

 vex in one direction and concave in the other. Movement in every 

 direction except axial rotation. As in the carpometacarpal joint of the 

 thumb. 



Enarthrosis. Ball-and-socket joint; capable of motion in all directions. 

 Articulations by a globular head received into a cup-like cavity. As in 

 hip- and shoulder-joints. 



Arthrodia. Gliding joint; articulations by plane surfaces, which 

 glide upon each other. As in carpal and tarsal articulations. 



The Kinds of Movement Admitted in Joints. 



The movements admissible in the joints may be divided into four kinds gliding, 

 angular movement, circumduction, and rotation. These movements are often, 

 however, more or less combined in the various joints, so as to produce an infinite 

 variety, and it is seldom that we find only one kind of motion in any particular 

 joint. 



Gliding movement is the most simple kind of motion that can take place in a 

 joint, one surface gliding or moving over another without any angular or rotatory 

 movement. It is common to all movable joints, but in some, as in the articu- 

 lations of the carpus and tarsus, it is the only motion permitted. This movement 



