[Tactics of surgical treatment for an inflammatory process of C0-C(I)-C(II) segments in the craniovertebral joint instability].

Pathological processes of C0-C(I)-C(II) segments, such as the clivus, atlas arch, dens, and body of the C, vertebra pose major problems for diagnosis and treatment. On removal of a sizable pathological focus, there may be instability of the craniovertebral segment, secondary displacement, and spinal compression syndrome. Therefore these patients frequently need stabilization of the craniovertebral transition. Patients with initial instability of the craniovertebral junction and subluxation of C(I)-C(II) segments are an intricate problem. The authors describe a rare case of an inflammatory process of C0-C(I)-C(II) segments with craniovertebtal junction instability. A differential diagnosis was made between chordoma, osteoblastoma, and an inflammatory focus at the above site. The following tactics was undertaken: the first stage was occipitospondylosynthesis with "Vertex" system with osteoplasty under Halo-traction; the second stage included transoral removal of a pathological removal of the dens and body of the C(II) vertebra, left lateral mass of the CI vertebra, and lower clivus. After removal of the pathological focus, there were portions of the abnormally changed bone with rarefaction without tumor tissue. Histologic studies revealed the signs of a chronic inflammatory process. A five-month follow-up showed that neurological symptoms and craniovertebral junction instability regressed. The control computed tomography made 5 months after surgery demonstrated the radical elimination of the pathology and the absence of C, vertebral subluxation. Thus, there is evidence for the tactics of successive operations (a stabilizing operation--posterior occipitospondylosynthesis (desirably under Halo-traction), followed by removal of a pathological focus via transoral access) in pathological processes of the craniovertebral C0-C(I)-C(II) in cases of initial craniovertebral junction instability.