Multi-slice spiral CT 3-dimensional reconstruction technique to treat multi-segmental degenerative spinal stenosis with traumatic instability of lower cervical spine

To study the feasibility of multi-slice spiral computed tomography (MSCT) 3-dimensional reconstruction technique in assisting cervical pedicle screw fixation (PSF) and double-door laminoplasty to treat multi-segmental degenerative spinal stenosis with traumatic instability (MDSTI) of lower cervical spine. From September 2006 to August 2007, PSF combined with double-door laminoplasty was performed in 9 patients with MDSTI of lower cervical spine. MSCT 3-dimensional reconstruction techniques, including volume rendering (VR) and multi-planar reconstruction (MPR), were used to assist preoperative diagnosis and measurement to guide the procedure. MPR was performed after operation. In coronal view, the degree of screw perforation was measured precisely and the different positions of pedicle screws were divided into three grades according to Richter's method. In axial view, the canal sagittal diameter and transverse area of every laminoplasty level were measured. Nine patients with MDSTI of lower cervical spine underwent PSF (total 44 screws). According to the classification of Richter, 72.7% (32/44) was in Grade 1 and 27.3% (12/44) was in Grade 2. No screw perforation occurred in Grade 3 and no screw revision was done for misplacement. No iatrogenic damage was observed. Double-door laminoplasty was performed in total 42 volumes. The postoperative sagittal diameter and transverse area of cervicals pinal c anal w e re s ignif icantly inc re as ed ( P