_:vb50939556 . _:vb50939556 . _:vb50939556 "url:https://www.ncbi.nlm.nih.gov/pubmed/27374772"^^ . _:vb50939556 . _:vb50939556 . _:vb50939556 . _:vb50939556 "A connective tissue disease characterized by ectopic ossification of the posterior longitudinal spinal ligament resulting in spinal cord compression, myelopathy and hyperreflexia."^^ .