Minimally invasive treatment of lumbar spinal stenosis with a novel interspinous spacer

Abstract

PurposeTo assess the safety and effectiveness of a novel, minimally invasive interspinous spacer in patients with moderate lumbar spinal stenosis (LSS).MethodsA total of 53 patients (mean age, 70 ± 11 years; 45% female) with intermittent neurogenic claudication secondary to moderate LSS, confirmed on imaging studies, were treated with the Superion® Interspinous Spacer (VertiFlex, Inc, San Clemente, CA) and returned for follow-up visits at 6 weeks, 1 year, and 2 years. Study endpoints included axial and extremity pain severity with an 11-point numeric scale, Zurich Claudication Questionnaire (ZCQ), back function with the Oswestry Disability Index (ODI), health-related quality of life with the Physical Component Summary (PCS) and Mental Component Summary (MCS) scores from the SF-12, and adverse events.ResultsAxial and extremity pain each decreased 54% (both P < 0.001) over the 2-year follow-up period. ZCQ symptom severity scores improved 43% (P < 0.001) and ZCQ physical function improved 44% (P < 0.001) from pre-treatment to 2 years post-treatment. A statistically significant 50% improvement (P < 0.001) also was noted in back function. PCS and MCS each improved 40% (both P < 0.001) from pre-treatment to 2 years. Clinical success rates at 2 years were 83%–89% for ZCQ subscores, 75% for ODI, 78% for PCS, and 80% for MCS. No device infection, implant breakage, migration, or pull-out was observed, although two (3.8%) patients underwent explant with subsequent laminectomy.ConclusionModerate LSS can be effectively treated with a minimally invasive interspinous spacer. This device is appropriate for select patients who have failed nonoperative treatment measures for LSS and meet strict anatomical criteria.

Interspinous Process Decompression Improves Quality of Life in Patients with Lumbar Spinal Stenosis

“…Using the SF-36 questionnaire instrument, these authors reported a percentage improvement of 41% over preoperative scores for the PCS. Also employing the SF-36, Shabat et al [ 17 ] found a PCS improvement of 40% in 53 IPD-treated patients with intermittent neurogenic claudication followed for 2 years.…”

Interspinous implants: are the new implants better than the last generation? A review

“…Other studies have shown improved ODI scores, ZCQ scores, and decreased VAS levels after implantation of the device [25]. Some studies have shown minor increases in ODI and VAS at 2-year time points after initial drop following surgery [19,26].…”

“…There is a general agreement on immediate decreased ODI or ZCQ with the use of IPDs. Some studies have demonstrated a "bounce back" effect after 1 or 2 years for both ODI [12,18,25] and ZCQ [33,37]. Although outcome in terms of ODI or ZCQ appear similar between last-and next-generation IPDs, the literature lacks sufficient randomized trials recruiting both types.…”

Interspinous implants to treat spinal stenosis

“…7). Unlike X-Stop, the Superion is delivered percutaneously as a single-piece through a cannula after dilators have opened the interspinous space [15,16]. The implant has superior and inferior cam lobes that rotate during deployment, so as to capture the superior and inferior spinous processes (Fig.…”