Hyun Bae, Philip Maurer, , Walter Peppleman, Walter Bulter, Raymond Linovitz, Erik Westerlund, Timothy Peppers, Isador Lieberman, Choll Kim, Federico Girardi

Study Design. Two multi-center FDA IDE pilot studies (Vertebroplasty: 20 patients; Kyphoplasty: 20 patients). Cortoss used for vertebral augmentation with the patient serving as his/her own control.
Purpose. To assess the feasibility and clinical outcome of the use of Cortoss in treating osteoporotic vertebral compression fractures (VCFs).
Methods. Patients meeting the inclusion/exclusion criteria were admitted into the study. Each study was run independently of the other; that is, there was no randomization between groups.
Results. Vertebroplasty: Average pain improved by a reduction in the VAS, from 74.1 preoperatively to 24.1 at 3 months, 28 at 6 months, and 32 at 12 months. Similarly, disability improved from a mean ODI score of 52% preoperatively to a mean score of 30% at 3 months and a mean score of 23% at 12 months. Kyphoplasty: Average pain improved by a reduction in the VAS, from 54 preoperatively to 22 at 3 months and 36 at 6 months. Similarly, disability improved from a mean ODI of 60% to a mean score of 33% at 3 months and a mean score of 35 at 6 months. Leakages, which were carefully analyzed on postoperative CT scans (1mm cuts), were similar in both groups and easily detected due to the radiopacity of Cortoss. In both the vertebroplasty and kyphoplasty groups, extravasations were all anatomically close to the vertebra and asymptomatic. No cardiac irregularities or pulmonary emboli were observed.
Conclusions. The results obtained in these two pilot IDE studies indicate that Cortoss is safe and effective in the treatment of osteoporotic VCF. The reductions in VAS pain scores are consistent with those reported in the literature using PMMA. The results are also consistent with those obtained in the prospective vertebroplasty study using Cortoss conducted in Europe. These studies suggest that a smaller volume of Cortoss appears to successfully reinforce the vertebrae and achieve symptomatic relief, as compared with the volumes reported in the literature for PMMA. This may be due to the interdigitated fill pattern observed with Cortoss which results in trabecular reinforcement. A larger, prospective randomized controlled IDE study to confirm these findings in under way.