Cost-effectiveness and quality of life after treatment of lumbar spinal stenosis with the interspinous distractor device (X-STOP) or laminectomy: a pilot study

OBJECTIVES: Primary end-point was to assess the cost-effectiveness of lumbar laminectomy versus X-stop insertion in patients with neurogenic claudication secondary to LSS. Secondary end-points were to compare quality of life, clinical outcomes, radiological parameters and complications within two groups. This is a pilot study to produce predictive models and allow sample size calculation. DESIGN: Multicentre randomised trial with two interventional arms, namely the lumbar laminectomy(LL) and X-stop(XS) groups. METHODS: Patients were recruited from two neurosurgical centres after fulfilling eligibility criteria and followed up for 1 year. Self-reported general quality of life and disease-specific questionnaires were used. The assessments were performed at discharge, 6 weeks, 6 and 12 months. Also, radiological parameters were analysed. RESULTS: In this pilot study 26 patients were identified of which 6 were excluded and 20 were randomised with 10 in lumbar laminectomy and 10 in X-stop(XS) group from June 2008 to January 2010. LL group incured lower costs than the XS group but showed no significant between-group differences in utility values (QALYs). We found that LL was perhaps more cost-effective than the XS but with uncertainty, suggesting the need for a larger trial. There were no significant differences between the two groups in quality of life, clinical outcomes or success rates but within group improvements were found. Importantly, 6 out of 10 patients (60%) from XS group crossed over to LL group. Sample size calculation with the original data showed the need for 25 patients in each arm to detect clinical significance in future clinical trial. CONCLUSION: Our results suggest that LL is possibly cheaper and more cost-effective than XS over a 1-year period, in National Health Service. No significant differences in quality of life and clinical outcomes between the two procedures were detected although this is only a pilot study with a small sample size

A randomized controlled trial of the X-Stop interspinous distractor device versus laminectomy for lumbar spinal stenosis with 2-year quality-of-life and cost-effectiveness outcomes

OBJECTIVE: Lumbar spinal stenosis (LSS) is a common and debilitating condition that is increasing in prevalence in the world population. Surgical decompression is often standard treatment when conservative measures have failed. Interspinous distractor devices (IDDs) have been proposed as a safe alternative; however, the associated cost and early reports of high failure rates have brought their use into question. The primary objective of this study was to determine the cost-effectiveness and long-term quality-of-life (QOL) outcomes after treatment of LSS with the X-Stop IDD compared with surgical decompression by laminectomy. METHODS: A multicenter, open-label randomized controlled trial of 47 patients with LSS was conducted; 21 patients underwent insertion of the X-Stop device and 26 underwent laminectomy. The primary outcomes were monetary cost and QOL measured using the EQ-5D questionnaire administered at 6-, 12-, and 24-month time points. RESULTS: The mean monetary cost for the laminectomy group was £2712 ($3316 [USD]), and the mean cost for the X-Stop group was £5148 ($6295): £1799 ($2199) procedural cost plus £3349 mean device cost (£2605 additional cost per device). Using an intention-to-treat analysis, the authors found that the mean quality-adjusted life-year (QALY) gain for the laminectomy group was 0.92 and that for the X-Stop group was 0.81. The incremental cost-effectiveness ratio was -£22,145 (-$27,078). The revision rate for the X-Stop group was 19%. Five patients crossed over to the laminectomy arm after being in the X-Stop group. CONCLUSIONS: Laminectomy was more cost-effective than the X-Stop for the treatment of LSS, primarily due to device cost. The X-Stop device led to an improvement in QOL, but it was less than that in the laminectomy group. The use of the X-Stop IDD should be reserved for cases in which a less-invasive procedure is required. There is no justification for its regular use as an alternative to decompressive surgery.Clinical trial registration no.: ISRCTN88702314 (www.isrctn.com)