Friday, November 1, 2002 3:16–3:44 pmSelect Poster Presentations: Incidence of remote and adjacent fractures after kyphoplasty

Abstract

Purpose of study: Osteoporosis compression fractures can be effectively treated with methyl methacrylate vertebral augmentation. A retrospective review was performed to determine the incidence of remote and adjacent level compression fractures after kyphoplasty.Methods used: A total of 175 patients treated for osteoporotic compression fractures at the Cleveland Clinic, from October 1999 to November 2002 were retrospectively reviewed. Sixty patients were excluded because of insufficient follow-up, less than 3 months, or malignancy-related fracture. The remaining 115 patients' office charts, hospital records, prospective database information, operative reports and radiographs were then individually analyzed. New fractures were identified based on changes from baseline imaging studies. Adjacent fractures were defined as a new compression fracture immediately rostral or caudal to a body treated with kyphoplasty. Remote fractures were defined as a new fracture with at least one vertebral body between the new fracture and the prior treated compression fracture. Demographic information, vertebral levels treated, number of two- and three-level adjacent kyphoplasties, time of follow-up, adjacent fractures and remote fractures were entered into a database, and statistical analysis (p<.05) was performed. Analysis included the correlation of the new fractures, adjacent fractures and remote fractures to demographics, single, two or multiple sites, along with two or three adjacent levels.of findings: A total of 225 vertebral bodies were treated with kyphoplasty in the 115 patients. Follow-up ranged from 3 to 26 months (mean, 10 months). Fifty-five single-level, 33 two-level and 27 multiple-level (three or more) procedures were performed. Twenty-six patients had two adjacent levels (ie, T6 and T7) and 16 had three adjacent-level kyphoplasty procedures performed during a single operation. Statistical analysis of the new fractures, adjacent fractures and remote fractures to demographics, single, two or multiple sites along with two or three adjacent levels did not correlate significantly. There were 30 subsequent compression fractures after initial kyphoplasty treatment. Seven patients had remote and 17 patients has adjacent fractures to their previously treated sites. The incidence of subsequent fracture per procedure was 1.3% (30 of 225), and the overall incidence of patients with subsequent fractures was 18.8% (22 of 115). Interestingly, 15 of these 22 subsequent fracture patients had secondary osteoporosis resulting from chronic steroid use. Therefore, only seven patients with primary osteoporosis developed a posttreatment compression fracture. These seven patients with subsequent fractures occurred in a population of 81 patients (excluding 34 secondary osteoporosis patients) resulting in an incidence of 8.6%. This can be extrapolated to a yearly incidence of 10.3%.Relationship between findings and existing knowledge: Previous studies have shown the annual incidence of a subsequent compression fracture to be approximately 20%, which is significantly higher than the incidence of 10.3% reported here for primary osteoporotic patients.Overall significance of findings: The kyphoplasty protocol with concurrent medical osteoporotic regimen appears not to increase and most likely to reduce the incidence of remote and adjacent fractures in this high-risk population. Therefore, this report argues against the theory that the further strength provided through methyl methacrylate augmentation results in an increased degradation of the other vertebral bodies, at least in the short-term.Disclosures: Device or drug: kyphon balloon tamp. Status: approved.Conflict of interest: Isador H. Lieberman, grant research support.