Anterior corpectomy and reconstruction with titanium mesh cage and dynamic cervical plate for cervical spondylotic myelopathy in elderly osteoporosis patients

Abstract

This retrospective study was to evaluate the relationship between osteoporosis and dynamic cervical plates in screw-plate or screw-bone interface of elderly cervical spondylotic myelopathy (CSM) patients. Retrospective study was conducted on elderly CSM patients, treated by anterior corpectomy and reconstruction with titanium mesh cages (TMC) and dynamic cervical plate between July 2004 and June 2007. All patients underwent bone mineral density (BMD) assessment in preoperation, and according to the osteoporosis degree they have been divided into two groups: moderate osteoporosis degree group and severe osteoporosis degree group. The clinical outcome [Japanese Orthopaedic Association score (JOA) and Visual Analogue Scale (VAS)], bone fusion assessment (CT mielogram), the change of titanium mesh cages and plate of cephalic screw-plate-angle (SPA) and cephalic endplate-plate-angle (EPA) of plain X-ray films were measured. The mean JOA score and recovery rate were not different between the two groups (P > 0.05). There was no loss of sagittal alignment after surgery in any patient, and no significant difference between both groups on lordosis measurements (P > 0.05). Although there was a significant difference of the cage subsidence rate between the two groups (P < 0.001), all patients had favorable bone union and none required additional treatment. The average changes of SPA were greater in A group patients than in B group patients, while the variation of EPA was higher in B group patients than in A group patients (P < 0.001). Despite the fact that there is a significant difference of the cage subsidence rate between the two groups no clinical outcome, nor sagittal alignment or fusion rate differences among groups was observed in elderly CSM patients.