Midline Spinous Process Splitting Laminoplasty Using Hydroxyapatite Spacers

Posterior decompression and reconstruction of the cervical spinal canal is a common treatment for cervical myelopathy. Since laminoplasty by midline splitting of the spinous processes was reported by Kurokawa in 1982 [1], we have used this method to treat cervical myelopathy due to spondylotic changes or ossification of the posterior longitudinal ligament (OPLL). Since 1986, we have used hydroxyapatite (HA) interspinous spacers instead of an iliac bone graft to maintain the enlargement of the cervical spinal canal [2]. There have been no problems with dislocation of the HA spacers, and good fusion has been achieved. The use of HA spacers eliminates the problems of buttock pain caused by harvesting autogenous bone from the posterior ilium. It also shortens the operating time,reduces intraoperative blood loss, and improves the range of motion below C2/3. Since 1995, we have also used a wire thread saw (T-saw) instead of an airtome for the splitting process.