Insufficiency fractures in rheumatic patients: misdiagnosis and underlying characteristics

To report 9 patients with rheumatic diseases referred to our observation due to presumed exacerbation of their rheumatic disease, subsequently diagnosed as stress insufficiency fractures, and to characterize the clinical profile of patients prone to this complication.

The medical history of the patients was reviewed with special emphasis on their rheumatic disease, its course, duration and management, their menopausal state, location and characteristics of the fracture, its presentation and the initial presumed diagnosis, the delay in diagnosis, imaging diagnostic tests performed and outcome. Three representative case reports are presented.

All 9 patients were women, 8 of them aged 50 years old or more, 8 with rheumatoid arthritis and 1 with polymyalgia rheumatica. They were all treated with corticosteroids and had reduction in their bone mass density when evaluated. Three of the patients presented with subcapital fracture of the femur, 4 had fractures of metatarsal bones and 2 had fractures of the distal tibia. In only one patient was a stress fracture initially suspected. Diagnosis was delayed by a mean of 31 days.

The diagnosis of stress fractures in patients with rheumatic diseases may often be delayed or missed, and thus improperly treated. Increased awareness of this entity is of importance for prompt diagnosis and correct management.