Kirschner wire-guided technique for inserting a second needle into inadequately filled vertebrae in vertebroplasty: a technical report

Abstract

Background context: Absence or inadequate filling of cement in the fractured vertebrae can cause unsatisfactory results in a vertebroplasty. Repeated needle insertion can reduce the incidence of recollapse at the cemented vertebrae. However, when inserting the second needle in the usual method, it takes the same time and radiation exposure as the first needle.

Purpose: To report a Kirschner wire-guided technique for inserting a second needle into inadequately filled vertebrae in vertebroplasty that can make the procedure simple, effective, and, most importantly, reduce the radiation exposure.

Study design: Description of a modified surgical technique with retrospective data analysis.

Patient sample: From January 2012 to December 2012, 87 percutaneous vertebroplasties were performed in our department to treat painful osteoporotic compression fractures. Seven adult patients (five women, two men; mean age: 75.7 years) had inadequate cement filling in the treated vertebrae that required the insertion of a second needle.

Outcome measures: Back pain was measured using the visual analog scale (VAS). The post-vertebroplasty anterior vertebral height and local kyphotic angle were used as the radiologic parameters. Intraoperative procedure time and fluoroscopy shots and postoperative complication were also evaluated.

Methods: The stylus of the first needle was inserted into the trocar to push the cement out of the trocar. The stylus was removed, a small diameter K-wire was inserted into the trocar, and the trocar was then removed. A second (new) trocar was inserted into the vertebral body following the track of the K-wire. When the new trocar reached the posterior 1/4 of the vertebral body, the K-wire was removed, the stylus was inserted, and the new needle was advanced to the anterior third of the vertebra. Cement was then injected into the new area until the filling was adequate.

Results: The immediate post-vertebroplasty anterior vertebral height was 23.31±1.95 mm, changed to 22.20±3.72 mm at final follow-up. The VAS decreased from a mean of 8.4 before vertebroplasty to 1.6 at the final follow-up. The follow-up duration ranged from 6 to 15 months (mean 12.6 months). There was no case of recollapse of the cemented vertebrae and no procedure-related complications. The procedure time of historical controls was 153.5 seconds, which reduced to 47.9 seconds by using this technique. The fluoroscopy shots of historical controls were 9.7 shots, which reduced to 2 shots by using this technique.

Conclusions: This report suggests that Kirschner wire-guided technique for inserting a second needle during vertebroplasty could make the procedure simple, effective, and, most importantly, reduce the procedure time and radiation exposure.

Keywords: Inadequate filling; Kirschner wire; Osteoporosis; Second needle; Vertebral compression fractures; Vertebroplasty.