Tendinous and ligamentous derangements in systemic lupus erythematosus

We assessed the prevalence of selected clinical and radiological features of tendinous and ligamentous derangements in a consecutive sample of patients with systemic lupus erythematosus (SLE).

Consecutive patients with SLE with no comorbidities attending a tertiary care center were prospectively assessed and underwent plain radiographic evaluation of the pelvis. Radiographs were analyzed by 2 blinded observers; radiographic sacroiliitis was graded 0 to IV. To better assess sacroiliac (SI) involvement, a computed tomography (CT) scan of the SI joints was performed in patients with grade III sacroiliitis. Hip joints and pubis were also assessed as described.

Of the 192 included patients, 89% were female, mean age was 36 years, and mean disease duration was 10 years. Inflammatory low back pain was reported by 10% of patients. Sacroiliitis of any grade was observed in 31 patients (16%), and grade III (confirmed on CT scan) sacroiliitis was observed in 6% (95% CI 3% to 9%). Osteitis pubis was diagnosed in 6% (95% CI 3% to 10%) and coxofemoral migration in 8% (95% CI 2% to 9%). Jaccoud's arthropathy was found in 23%. Demographic and clinical variables were not statistically associated with radiographic sacroiliitis.

Sacroiliitis and other tendinous and ligamentous derangements are not uncommon in patients with SLE. Based on these features and on previous reports, the term "SLE-related tendinous and ligamentous derangements" may be used to establish a common framework for further research and reporting.