Demographic and clinical characteristics of spinal calcinosis in systemic sclerosis: Possible association with peripheral angiopathy.

The objective was to evaluate the demographic and clinical characteristics of systemic sclerosis (SSc) patients with spinal calcinosis. Paraspinal and intraspinal calcinosis was assessed blindly by orthopedic surgeons specializing in spinal diseases using chest high-resolution computed tomography (CT) that was performed for the screening and prospecting of interstitial lung disease in 159 Japanese SSc patients. Among these patients, we identified 27 (17%) with spinal calcinosis, and the most common site was cervical level at 77.8% (21/27). The frequency of spinal calcinosis in the late stage was higher than in the early stage (44.4% vs 29.6%). Multiple calcinosis was identified in 18.5% (5/27). The frequency of paraspinal calcinosis only was 59.3%, intraspinal calcinosis only 18.5%, and both intraspinal and paraspinal calcinosis 22.2%. Among SSc patients, 4.4% (7/159) had CT-based evidence of spinal cord compression. Among cases with spinal cord compression, only one had neurological symptoms, and surgical removal improved the symptoms. The other six SSc patients with spinal calcinosis (3.8% of 159) had no symptoms. Male sex (29.6%) and severe peripheral vasculopathy such as digital ulcers (55.6%) and acro-osteolysis (33.3%) were significantly more frequent in the SSc patients with spinal calcinosis than in the SSc patients without spinal calcinosis (10.6%, 32.6% and 14.4%, respectively). Our results suggest that severe peripheral vasculopathy may be associated with the development of spinal calcinosis. Because SSc patients are prone to spinal calcinosis, when SSc patients claim symptoms such as pain, numbness and movement disorder of the extremities, spinal calcinosis is a complication that should be taken into consideration.