Purpose: The aim of this study was to improve the accuracy of puncture to the median vertebral body using the unilateral transpedicular approach on percutaneous vertebroplasty (PVP). We have developed and evaluated a simple puncture simulation method based on the puncture angle determined by preoperative computed tomography (CT).
Material and methods: Two groups were evaluated. The first (group A) comprised 23 patients (34 vertebral bodies) who had undergone PVP without preoperative puncture simulation before May 2004, and the second group (group B) comprised 24 patients (39 vertebral bodies) who had undergone preoperative puncture simulation and PVP after May 2004. CT in the prone position was performed, and the puncture angle on CT (PAC) via the vertebral arch pedicle targeting the anterior one-third median site of the vertebral body was determined. Puncture was performed by targeting the isocenter established on a fluoroscopic monitor based on the PAC. Determinations were made of the success rate (SR) of the median puncture of the vertebral body, the effect of treatment using the visual analogue score, and the overall procedural time between groups A and B.
Results: The SR was 56% (19/34 vertebral bodies) in group A, and 97% (37/38 vertebral bodies), including only one vertebral body in which it was difficult to perform the unilateral approach on CT images, in group B, with the difference being significant by Student's t-test (P < 0.001). Among patients with available follow-up data, the unipedicular and bipedicular approaches achieved adequate pain relief with mean decreases in pain severity of 5.1 +/- 2.6 and 5.9 +/- 2.8, respectively. No significant differences in the treatment effect between the two groups was observed (P = 0.811). The overall procedure time per puncture was shorten for the simulation group (36.0 min) than for group A (73.1 min), as shown by regression analysis.
Conclusion: The preoperative PAC determination for PVP under fluoroscopy increased the completion rate of PVP by the unilateral transpedicular approach. This method should be accepted from the viewpoint of burden reduction on patients and surgeons.