Interspinous process devices versus standard conventional surgical decompression for lumbar spinal stenosis: cost-utility analysis.

Abstract

BACKGROUND CONTEXT:

In the 1980s, a new implant was developed to treat patients with intermittent neurogenic claudication caused by lumbar spinal stenosis (LSS). This implant is now widely used.

PURPOSE:

The objective of this study is to determine whether a favorable cost-effectiveness for interspinous process devices (IPDs) compared with conventional bony decompression is attained.

STUDY DESIGN/SETTING:

Cost-utility analysis was performed alongside a double-blind randomized controlled trial. Five neurosurgical centers (including one academic and four secondary level care centers) included participants for this study.

PATIENT SAMPLE:

One hundred fifty-nine patients with LSS were treated with the implantation of IPD and with bony decompression. Eighty participants received an IPD, and seventy-nine participants underwent spinal bony decompression.

OUTCOME MEASURES:

Outcome measures were quality-adjusted life-years (QALYs) and societal costs in the first year (estimated per quarter), estimated from patient-reported utilities (US and The Netherlands EuroQol 5D [EQ-5D] and EuroQol visual analog scale) and diaries on costs (health-care costs, patient costs, and productivity costs).

METHODS:

All analyses followed the intention-to-treat principle. Given the statistical uncertainty of differences between costs and QALYs, cost-effectiveness acceptability curves graph the probability that a strategy is cost effective, as a function of willingness to pay. Paradigm Spine funded this trial but did not have any part in data analysis or the design and preparation of this article.

RESULTS:

According to the EQ-5D, the valuation of quality of life after IPD and decompression was not different. Mean utilities during all four quarters were, not significantly, less favorable after IPD according to the EQ-5D with a decrease in QALYs according to the US EQ-5D of 0.024 (95% confidence interval, -0.031 to 0.079). From a health-care perspective, the costs of IPD treatment were higher (difference €3,030 per patient, 95% confidence interval, €561-€5,498). This significant difference is mainly because of additional cost of implants of €2,350 apiece. From a societal perspective, a nonsignificant difference of €2,762 (95% confidence interval, -€1,572 to €7,095) in favor of conventional bony decompression was found.

CONCLUSIONS:

Implantation of IPD as indirect decompressing device is highly unlikely to be cost effective compared with bony decompression for patients with intermittent neurogenic claudication caused by LSS.

TRIAL REGISTRATION:

Dutch Trial Register Number: NTR1307.

• Authors: M Elske van den Akker-van Marle, Wouter A Moojen, Mark P Arts, Carmen L A M Vleggeert-Lankamp, Wilco C Peul, Leiden-The Hague Spine Intervention Prognostic Study Group (SIPS)
• Journal: The spine journal : official journal of the North American Spine Society (Spine J) Vol. 16 Issue 6 Pg. 702-10 (06 2016) ISSN: 1878-1632 [Electronic] United States
• PMID: 25452018 (Publication Type: Comparative Study, Journal Article)
• Copyright: Copyright © 2014 Elsevier Inc. All rights reserved.

Topics

• Adult
• Aged
• Aged, 80 and over
• Cost-Benefit Analysis
• Decompression, Surgical (economics, instrumentation, methods)
• Double-Blind Method
• Female
• Humans
• Lumbar Vertebrae (surgery)
• Male
• Middle Aged
• Netherlands
• Prostheses and Implants (adverse effects, economics)
• Quality of Life
• Quality-Adjusted Life Years
• Spinal Stenosis (surgery)