Total (anterior and posterior) decompression of the spinal cord: surgical treatment for combined ossification of the posterior longitudinal ligament and yellow ligament of the thoracic spine.

The ossification of the posterior longitudinal ligament (OPLL) combined with ossification of the yellow ligament (OYL) in the thoracic spine can compress the spinal cord from the anterior and posterior direction, resulting in serious myelopathy. For these cases we devised a treatment consisting of two steps, total decompression of the spinal cord. The first step is removal of ossified yellow ligament posteriorly following wide laminectomy and the second step is removal of ossified posterior longitudinal ligament anteriorly, followed by interbody fusion. As the final procedure of the first step, two parallel deep gutters, covering the complete length of the ossified ligament to be removed anteriorly, are drilled from the posterior direction into the vertebral body along both sides of the dura. This pretreatment makes removal of the ossified ligament from the anterior, during the second stage, much easier and safer. This operation appears to be a promising operative procedure from our seven case experiences so far.