Rheumatism. 533 



lesion becomes the seat of active and perhaps permanent rheuma- 

 tism. Unusual overwork and fatigue of given joints and muscles 

 induce a similar pre-disposition, and hai)itual overexertion, sprain, 

 injury or inflammation affecting repeatedly the rheumatic organ 

 tends to fix the process in chronic form. 



Articular lesions. These tend to concentrate as a form of in- 

 flammation in the synovial membranes, but usually implicate 

 all the constituent structures of tlie joint, capsular and binding 

 ligaments, cartilage and fibro-cartilage, articular lamella and 

 osseous tissue. The synovial membrane may show only slight 

 hypi^raemia, or in severe cases it may be congested, red, thick- 

 ened or even extensively infiltrated with a serogelatinoid liquid. 

 These lesions are most marked around the line of attachment 

 on tlie articular surface and in the synovial fringes. The svno- 

 via is usually in excess, distending the capsule and is whitish, 

 opaque, flocculent or more or less deeply colored with red. It 

 contains flakes of fibrine. leucocytes, albumen and it may be red 

 blood globules. Pus cells are usually absent unless in distinctly 

 infective cases. Coagula and false membranes floating from or ad- 

 herent to the solid tissues, may be present in considerable amount 

 and if these become organized they tend to lay the foundation for 

 future stiffening and rigidity. In and beneath the serosa, cell 

 proliferation may go on actively, especially in the synovial fringes. 

 The synovia is usually neutral or slightly alkaline, though in rare 

 instances it has proved to be acid. 



The inflammation of the .synovial membrane of the joint often 

 extends to those of the adjacent tendons, implicating at the .same 

 time the tendons and their fibrous sheaths. Softening and rup- 

 ture of the tendons have been noted by different ob.servers (per- 

 forans, (3ger ; gastrocnemii, Trasbot : suspensory ligament, Olli- 

 vier). 



The articular cartilages and the fil)ro-cartilages may be the seat 

 of congestion, with ramified or uniform redness, and areas of 

 swelling, softening, al^sorption, erosion and ulceration, the ulcers 

 varying in size from a millet seed upward. The nuclei increase 

 in size and the cartilage cells multiply. In chronic forms calci- 

 fication is not uncommon. 



The articular lamella and subjacent bone may show inflamma- 

 tion with increased vascularity, softening and even ulceration. 



