[Physiopathology of primitive arthrosis. Problems and hypotheses].

The origin and the evolution of the so-called primitive arthrosis represent two problems that hypotheses, developed by the authors, contribute to elucidate. Primitive arthrosis begins with a prearthrosic chondropathy which looks like the changes in the joint cartilage due to aging and due both to local conditions preventing the nutrition of the cartilage and to general factors causing failure of the system regulating the synthesis and the differentiation of articular tissues. These conditions are also relevant to primitive monoarthrosis, relatively rare in comparison with the frequency of secondary arthrosis and in comparison with arthrosis disease, which is the prototype of primitive polyarthrosis.

[Histological aspects of the sarcomatous degeneration of bone in Paget's disease].

After a critical review of the literature and an enquiry based on 70 cases, the author confirms that osteogenic sarcomas and fibrosarcomas constitute the usual means of sarcomatous degeneration in bones affected by Paget's disease. Giant-cell tumours present a distinct group. The problems posed by the initial stages of the malignant transformation and the osteosarcomas with multiple centres are then discussed.

[Articular manifestations of cryoglobulinemias].

Manifestations are found in the joints in 27-50 percent of patients with cryoglobulinaemia. They include arthralgia, or less frequently arthritis of distal oligo-articular topography, predominantly in the lower limbs. These manifestations consist of pure synovitis - nonexudative, nondestructive, and usually recurrent.