[Involvement of the shoulder in rheumatoid arthritis]

The course of rheumatoid arthritis (R.A.) in the shoulder is evaluated in 100 patients in a retrospective study and in 73 patients in a prospective study. The involvement of the shoulder may occur at an early stage of the disease. However, usually it causes a significant handicap at a later stage. The retrospective study shows that 62% of the patients hospitalized between 1976 and 1992 for R.A. complained of pain, reduction in range of motion and functional disability of one or both shoulders. However, these historic cases cannot be used for a radiological study because the shoulders have been radiographed in 17% of cases only, probably because of the poor possibilities of surgical therapies available at this time. The survey of 72 patients received at the out- patient clinic between september 1992 and december 1993 who had a radiograph of the shoulder is the basis for the description of the progress of the disease. The erosions appear at the border of the cartilage where the synovium is attached and refers mainly to the cephalic articular cartilage. Narrowing of the subacromial space is often present with early appearance of subluxation in the cranial direction. The destruction often prevails in the area of humeral head but cases with predominant global joint space narrowing or with destruction of glenoid labrum and fossa exist as well. Secondary osteoarthritis was often observed. The involvement of the shoulders is not always symmetric. Unilateral involvement has been observed. The different evolutive processes will be illustrated and their frequency evaluated. The forms with predominant cephalic destruction constitute the best indications for total shoulder arthroplasty.