KINDS OF JOINTS 33 



point at which it might be pried out, or dislocated. At 

 that point, the ligaments on the farther side of the joint 

 become tight and thereby prevent dislocation. Examples 



Triceps muscle 



Hu 



Brachialis muscle 

 (assists biceps) 



Bursa (much distended) 

 Synovial sac (much 



distended) 



Articular cartilages 



Circular ligament of 

 head of radius 



Tendon of biceps 

 Bursa (much distended 



Radius 



Ligament between 

 radius and ulna 



Ulna 



FIG 26. Section of elbow, showing both a hinge joint (humenis and ulna), and a 

 pivot joint (radius and ulna). (The surfaces of the elbow joint are shown un- 

 naturally separated, and the synovial sac and bursae injected with fluid.) 



of ball-and-socket joints are the shoulder and hip and in a 

 measure the knuckles. 



