Association of radiographic findings in hand X-ray with clinical features and autoantibodies in patients with systemic sclerosis

Musculoskeletal involvement is one of the major causes of impairment in daily life of patients with systemic sclerosis (SSc). Several hand radiographic findings can be seen in SSc patients; however, their association with clinical features and autoantibodies remains unclear. Here, we analyzed 124 SSc patients with their hand X-rays and clinical and serological features. Abnormal findings in hand X-rays including acro-osteolysis, calcinosis, flexion contracture, erosive change, joint space narrowing, and subluxation were observed in 110 patients (68%). These X-ray findings were more prevalent in patients with longer disease duration and digital ischemic changes. The majority of erosions were typical for erosive hand osteoarthritis, which was seen in 19% of patients. Hand X-ray findings were associated with involved organs; acro-osteolysis with interstitial lung disease, calcinosis with pulmonary arterial hypertension and gastrointestinal tract involvement, and flexion contracture with gastrointestinal tract involvement. Those findings were also relevant to autoantibodies; acro-osteolysis was more common in SSc patients with anti-Scl70 antibody but less in patients with anticentromere antibody. Calcinosis was more prevalent in patient with anticentromere antibody. In our study, organ involvements and SSc-associated autoantibodies showed associations with hand radiographic abnormalities. Hand X-ray findings might reflect underlying pathogenesis and autoantibody profiles in SSc patients.Key Points• Hand X-ray abnormalities were observed in approximately two-thirds of patients with SSc.• Erosive osteoarthritis was more prevalent in SSc patients than general population.• Hand X-ray findings were associated with disease duration, organ involvements, and SSc-associated autoantibodies, reflecting underlying pathogenesis.