ARTICULATIONS OR JOINTS 27 



dons: in front by the tendon of the anterior extensor muscle; 

 on the sides by two lateral ligaments, one on each side ; behind 

 by the posterior ligament and the tendons of the shallow and 

 deep flexor muscles which pass over the posterior of the joint. 

 The posterior ligament is really a thick strong pad of fibro- 

 cartilage. 



Movements. — Flexion and extension, together with a limited 

 lateral movement. 



Practical application and disorders. — Among the more com- 

 mon disorders of articulations are sprains, dislocations, syno- 

 vitis, arthritis, open joint, and anchylosis. 



A sprain is an injury due to a strain of articular structures, 

 especially ligaments, overstretching or actually rupturing the 

 fibers. Sprains are characterized by the usual symptoms of 

 inflammation, pain, heat, swelling, etc.; disinclination to flex 

 the joint or bear weight upon it, most common at ankle, hock 

 and stifle. Treat by complete rest, fixation if necessary, cold 

 water or ice several days, then massage and light use soon as 

 appears advisable. 



Dislocation may be partial or complete and implies that a bone 

 is out of its proper place at an articulation. This is usually 

 the result of severe injury, and it is frequently associated with 

 sprain of ligaments or other structures. It is indicated by 

 change in length or shape of the limb, by either more or less 

 mobility, and frequently by pain, heat, and swelling. Reduce 

 the dislocation by pulling and pushing the bone back into place 

 and treat as for sprain. 



Synovitis is an inflammation of the synovial membrane, usually 

 the result of injury or infection. Very mild form is seen in 

 bog spavins, wind puffs, etc. Severe and acute cases occur, 

 for example, in connection with open joint where we have ex- 

 treme pain and lameness. The most conspicuous symptom is 

 bulging of the synovial capsule with or without lameness. 



Arthritis implies a general inflammation of local articular 

 structures, including synovial membrane (synovitis), articular 

 cartilage, bone, ligaments, etc. Arthritis is characterized espe- 

 cially by lameness, local tenderness, pain and swelling. Ar- 

 ticular rheumatism is a good example. Bone spavins and articu- 

 lar ring bones illustrate the results of an arthritis in which 

 articular cartilages and adjacent bones are seriously involved. 

 Treatment of severe arthritis must be left to the veterinarian. 



