Authors' objectives:

The purpose of this report is to assess the usefulness of intervertebral disc replacement for spine degenerative diseases.

Authors' results and conclusions: In 2003, De Kleuver et al conducted a systematic review. They evaluated 9 case series with a total of 564 artificial discs (Charit and Acroflex). The authors concluded that the procedure has a high rate of reoperations, that it should be considered as an experimental procedure and that, at present, data are not enough to adequately assess performance of disc replacement. However, these series are before 2000. In 2003, Zigler et al report a RCT with Prodisc II (28 patients) versus lumbar spine fusion in the control arm (11 patients), with a 6-month follow-up. Hospital stay was shorter in the Prodisc arm. After 6 months, there were no statistically significant differences in pain scales. Guyer et al. (2004), compare the Charit disc with the BAK arthrodesis technology in a RCT with 144 patients and a 24-month follow-up. Results were evaluated according to the Oswestry Disability Index and were similar for both methods. In a multicenter RCT, Blumenthal et al (2005) compared the Charit disc (n=205) with intervertebral fusion with fusion cages (n=99). There were no significant differences in rate of complications for both groups. According to the authors, clinical success was achieved in 57.1% of patients in the Charite group and 46.5% in the surgical control group (p<0.001). The RCT considered presents several methodological problems, including, among others, the loss to follow-up of a group of patients, which make result interpretation difficult. Case series with longer follow-ups (Tropiano, Lemaire) report results which are similar to the preceding ones. As regards experience with the Bryant cervical disc, the quality of the evidence is even poorer. Most common complications (3-50%) were pain progression, spine infection, vascular and presacral plexus damage. Also, other transient or temporary neurological complications are reported. Coverage policy In October, 2004, the U.S FDA approved the use of the Charit artificial disc. In Canada, the use of the Bryant cervical disc has also been licensed. The U.S BlueCross BlueShield, ICSI and CIGNA do not cover this indication. AETNA covers it in highly selected patients.

Authors' recommendations: To a great extent, the evidence supporting the artificial disc effectiveness and safety comes from the case series. Study populations are small and heterogeneous. In general, there are few RCTs with small control groups and with significant methodological defects. This makes it difficult to compare studies. Therefore, there is inadequate evidence supporting the clinical use of this technology, especially beyond 24 months of use. When all the studies are considered together, it is not possible to show a clear advantage of this technology over other surgical procedures, especially, in the case of spinal fusion. As to cervical discs, it is not possible to establish their safety and efficacy because no direct comparative data against other options such as dissectomy with or without fusion are available.

Authors' methods: Overview

Project Status: Completed

URL for project: http://www.iecs.org.ar/

Year Published: 2006

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: Argentina

Organisation Name: Institute for Clinical Effectiveness and Health Policy

Contact Address: Dr. Emilio Ravignani 2024, Buenos Aires - Argentina, C1414 CABA

Contact Name: info@iecs.org.ar

Contact Email: info@iecs.org.ar

Copyright: Institute for Clinical Effectiveness and Health Policy (IECS)