Study for the hereditary trait of OPLL

Hereditary trait of OPLL was studied radiographycally in twenty-two patients suffering from this disorder in the cervical spine. This study included ninety-nine persons of twenty-two families. The familial incidence of OPLL was found in nine families of twelve persons. Other vertebral hyperostotic changes such as ossification of the anterior longitudinal ligament (more than Stage III) or the yellow ligaments were prominent in the family members in whom the familial traits were recognized.