Measurements of bone mass were carried out by X-ray microdensitometry of the second metacarpus in 120 cases of OPLL in the cervical spine and 61 cases of control.
Bone density was significantly higher in the non-myelopathy group of OPLL, but significantly lower in the severe myelopathy group of OPLL than in the control group. There was no difference between the group of continuous and mixed type and that of segmental type.
