This study evaluates factors related to myelopathic
symptoms in patients with ossification of the posterior longitudinal
ligament (OPLL). A total of 87 patients with OPLL were included.
Of these, 53 (Group I) had no symptoms or presented with neck pain
and radiculopathy and 34 (Group II) had myelopathic symptoms. Gender, age,
and history of trauma were evaluated in the two groups. The range
of movement of the cervical spine was measured using plain radiographs.
The number of involved segments, type of OPLL, and maximal compression ratio
were analysed using CT and signal change in the spinal cord was
evaluated using MRI. The patients’ age was found to be significant (p = 0.001). No
difference was found between gender and the range of movement in
the two groups. The maximum compression of the spinal canal showed
a difference (p = 0.03). The signal change of the spinal cord was
different between the two groups. In patients with OPLL of the cervical
spine, myelopathic symptoms are not related to the range of movement
or the number of involved segments.
We reviewed 87 patients who had undergone expansive cervical laminoplasty between 1999 and 2005. These were divided into two groups: those who had diabetes mellitus and those who did not. There were 31 patients in the diabetes group and 56 in the control group. Although a significant improvement in the Japanese Orthopaedic Association score was seen in both groups, the post-operative recovery rate in the control group was better than that of the diabetic group. The patients’ age and symptom duration adversely affected the rate of recovery in the diabetic group only. Smoking did not affect the outcome in either group. A logistic regression analysis found diabetes and signal changes in the spinal cord on MRI to be significant risk factors for a poor outcome (odds ratio 2.86, 3.02, respectively). Furthermore, the interaction of diabetes with smoking and/or age increased this risk. We conclude that diabetes mellitus, or the interaction of this with old age, can adversely affect outcome after cervical laminoplasty. However, smoking alone cannot be regarded as a risk factor.