Y. Morio et al., Radiological pathogenesis of cervical myelopathy in 60 consecutive patients with cervical ossification of the posterior longitudinal ligament, SPINAL CORD, 37(12), 1999, pp. 853-857
Study design: The radiological pathogenetic factors for cervical myelopathy
in 60 consecutive patients with cervical ossification of the posterior lon
gitudinal ligament (OPLL) were investigated retrospectively.
Objective: To clarify which patients with OPLL will develop cervical myelop
athy.
Methods: Sixty consecutive patients with OPLL were radiologically assessed
comparing the myelopathic patient group (M group, n=41) and the mild or non
-myelopathic patient group (non-M group, n=19).
Results: The narrowing ratio of the spinal canal in the M group (47.1%) was
significantly greater (P=0.026) than that in the non-M group (38.3%). The
two groups showed a significant difference (P=0.0016) with regard to the Pa
vlov ratio (M group, 0.73; non-M group, 0.84). The total range of motion of
the cervical spine did not differ between the two groups but the per cent
range of motion was significantly greater (P = 0.037) in the M group than i
n the non-M group.
Conclusion: This study suggests that factors important in the onset or aggr
avation of myelopathy are factors related to pathological compression by OP
LL, cervical soft disc herniation! developmentally narrow spinal canal, and
local or non-proportional hypermobility.