title: Spinal bone density following spinal fusion.
abstract: Spinal bone densities were assessed in 25 patients following lumbar fusion and bracing, in an attempt to study bone remodeling by noninvasive methods. Dual-photon densitometry was used to study specific areas of autologous bone grafts and adjacent vertebrae above the fusion mass. Measurements were made preoperatively and at 6-week intervals postoperatively. The data for the first 12 months postoperatively are reported here. In all patients there was at first a consistent loss in density in the vertebrae above the fusion mass, averaging 15.7%. This was followed by a gradual density increase such that by 1 year postoperatively, in 60% of the subjects, the density of these vertebrae was higher than the preoperative level. In the grafted areas, bone changes were cyclical, demonstrating a remodeling pattern consistent with that described in animal literature for graft healing and also consistent with modern bone remodeling theory. There was a general tendency toward a gradual increase in the density of the fusion mass.
authors.affiliation: North Carolina Spine Center, P.A., Chapel Hill Bone Diagnostic & Research Foundation.
authors.forename: H J
authors.initials: HJ
authors.lastname: Lipscomb
authors.forename: S A
authors.initials: SA
authors.lastname: Grubb
authors.forename: R V
authors.initials: RV
authors.lastname: Talmage
mesh_terms: D000328:Adult; D001846:Bone Development; D001862:Bone Resorption; D016025:Bone Transplantation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000502:physiology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D011182:Postoperative Care; D011877:Radionuclide Imaging; D013123:Spinal Fusion; D013997:Time Factors; D014182:Transplantation, Autologous