Objective: To evaluate the incidence of involvement and nature of destruction of glenohumeral (GH) joints in a prospectively followed cohort of 74 patients with seropositive and erosive rheumatoid arthritis (RA).
Methods: At the 15 year followup radiographs of 148 GH joints were evaluated, and the grade of destruction was assessed by the Larsen method.
Results: Erosive involvement (Larsen grade 2) was observed in 71/148 (48%) GH joints in 41/74 (55%) patients; 30 patients had bilateral and 11 unilateral involvement. The incidence of mild erosions (Larsen grade 2) was 401148 (27%), and of severe (Larsen 3-5) 31/148 (21%). The 11 most severely involved (Larsen grade 5) joints were seen in 6 (8%) patients. Erosions were most often (61/71 joints) observed on the superolateral articular surface of the humerus. Glenoidal involvement was less common (28/71 joints). The Larsen score (0-100) for peripheral joints correlated significantly with the GH joint Larsen grade on both sides (p < 0.001).
Conclusion: After 15 years more than half the patients with RA showed definite involvement and 1 in 4 had severe destruction of the GH joint. The greatest destruction was almost always bilateral.