General Session: Innovative Technologies I - Hall F

Presented by: J. Zigler

Author(s):

R. Guyer(1), J. Zigler(1), S. Blumenthal(1), D. Ohnmeiss(2)

(1) Texas Back Institute, Plano, TX, United States
(2) Texas Back Institute Research Foundation, Plano, TX, United States

Abstract

Introduction: One concern expressed about lumbar total disc replacement (TDR) has been safety. One measure of safety is the need for subsequent surgery to removal or revise an implant. This may be of particular importance considering TDR removal/revision generally requires re-operation through the anterior approach with the corresponding increased risk of vascular injury. The purpose of this study was to analyze the incidence of, and reasons for, removal or revision of lumbar TDR devices.

Methods: A consecutive series of 1,707 lumbar TDR patients, beginning with the first case experience in 2000, was reviewed to identify those undergoing re-operation for TDR removal or revision. Only patients who were at least 6 months post-operative were included. Among the 1,707 patients, the mean follow-up was 42.7 months with a median of 30 months and a maximum of 195 months. Six different devices were used in the series. For each case of device removal/revision, the reason, duration from index surgery, and procedure performed were recorded.

Results: In the series of 1,707 patients, there were 17 patients who underwent TDR removal (0.99%) and 3 additional patients underwent TDR revision (0.17%). The rates based on the total number of 2,023 TDR devices implanted in the 1,707 patients, were 0.89% removals and 0.15% revisions. The reasons and timing of removal/revisions are described in the table. With respect to timing, 40% of the removals/revisions occurred within one month after the index surgery, and a total of 85% occurred within 2 years of implantation. Of note, 40% of the revisions/removals occurred in the first 25 TDR cases performed by individual surgeons. There were no vascular complications causing clinical sequelae during any of these removal/revision surgeries.

Discussion: In this large patient series, 1% of lumbar TDRs were subsequently removed or revised. Only one revision was related to device failure or wear. Many of the subsequent procedures were performed within a month of the implantation. Also of note, many occurred within the first 25 TDR cases for individual surgeons, suggesting a learning curve. In cases of TDR removal/revision, as with any repeat anterior spine surgery, one should be acutely aware and prepared for vascular injury should it occur. The low rate of removal/revision in this large institutional experience over a 17 year period provides support for the safety of these devices.

Overview of lumbar TDR removals/revisions.]