V Radchenko. Bioactive ceramic implants in spine surgery. The Internet Journal of Minimally Invasive Spinal Technology. 2008 Volume 3 Number 4.
The problem of spine deseases remains actual and the questions of surgical treatment require profound studies. Increase of efficiency of patients’ treatment can be achieved by usage of new implant materials such as bioactive ceramics based on hydroxyapatite (HA) and by development of optimal ways of surgical operation. Goal of the study: to analyse results of experimental and clinical developments on HA usage in spine surgery.Materials and methods. Experiments were carried out on 168 rats with the usage of morphologic and biomechanical methods. Traumatic defects in vertebrae and intervertebral discs were made with dental drill in lumbar spine section using front access. Defects were filled in with HA of different structure (compact and porous granules). Compact HA was used for spine segment stabilization after removal of intervertebral disc. Clinical part of the work was done basing on the analysis of treatment results of 91 patients with different types of defects of thoracic and lumbar parts. The treatment was carried out with the usage of both compact and porous HA samples. Results: Granular HA implantation into the vertebra is followed by the creation of connection zone with high density of osteoblast cells.This results in marked osteointegration and formation of close bone-ceramic connection. Osteogenesis process was more visible when porous granules were used. Bone tissue was formed in ceramic pores. After implantation of compact HA samples high level of osteointegration was observed which was determined with the help of osteointegration index. After 3 and 6 months osteointegration index increased. Biomechanical studies of vertebra segments with ceramics showed that the impact of critical load on vertebra segments does not lead to fractures in the implantation area of both porous and compact HA. In all situations critical load corresponds to one for intact vertebra segments. We carried out results analysis of 91 patients’ with defects of thoracic and lumbar spine sections treated with compact and porous HA taken separately and combined. Implantation of HA granules into closed space (vertebra body and intervertebral space) provides for intervertebral support in combination with posterior spine fusion metal construction. Advantage of HA granules usage is little invasive surgery. Compact HA samples might be used with frontal access to vertebra body (if it is not possible to create closed space).Conclusion: Developed options of surgical treatment of traumatic spine defects allowed achievement of optimal correction of spine deformation with different types of trauma and keeping the stability of fixation for the period of formation of bone-ceramics ingrowth.