Abstract
Anterior decompression and adequate spine fixation in patients with cervical radiculopathy and myelopathy are essential for functional restoration of cervical spine. In this study, we performed evaluation and comparative radiological assessment of several types of spinal implants in terms of bone block formation, sagittal alignment and effectiveness as a structural support.
Materials and Methods: From 1993 to 2003, 165 patients with radiculopathy and myelopathy due to degenerative disease of cervical spine were operated on. The age of patients was 32–74 years (mean age 57, 8). The interbody fusion was performed by several methods.
Group1. Autograft – 91 patients
Group 2. TiNi alloy cages – 74 patients.
Group 3. Varilift expandable cages without plate fixation – 22 patients
Group 4. Verilift cages with plate fixation – 8 patients
Group 5. Bone substitute spacer and plate fixation – 3 patients.
Results: In groups 1 and 2, the bone and bone-metal block was formed during the first 3–4 months after surgery in all patients. There were no cases of bone resorbtion around the TiNi cages or loosening of the device. In patients with one-level (15 patients) interbody fusion by Varilift cages (group 3); formation of the bone block during the same time period was observed in 14 out of 15 patients. In cases with two-level fusion (7 patients), the bone block at the second level was not formed for longer than 6 months. There were 7 cases of subsiding and segmental kyphosis. In group 4, we did not detect any cases of loosening, subsiding or segmental kyphosis. In group 5, no bone block formation was observed after 6 months despite plate fixation.
Conclusions: A high fusion rate was achieved after a single or multi-level discectomy and interbody fusion by autograft and TiNi cages, which did not subside due to their design and superelasticity and can therefore be used without plate fixation. Varilift cages were also very effective, but if used without plate fixation may be associated with subsiding effect. The use of the bone substitute spacer is questionable in cervical spine surgery. Cervical plate fixation is effective as a prophylactic measure against segmental kyphosis in all types of interbody fusion.
The abstracts were prepared by Ms Orah Naor. Correspondence should be addressed to Israel Orthopaedic Association at PO Box 7845, Haifa 31074, Israel.
