155. Interspinous process decompression with the Superion® Spacer for lumbar spinal stenosis: real world experience from a device registry

Abstract

BACKGROUND CONTEXT Interspinous process decompression (IPD) with stand-alone spacers has demonstrated excellent long-term clinical benefit for patients with lumbar spinal stenosis (LSS). PURPOSE Real-world experience with interspinous process decompression. The primary aim of the registry is to prospectively collect a set of perioperative and clinical outcomes among patients treated with stand-alone IPD for symptomatic LSS. STUDY DESIGN/SETTING Stand-alone IPD using the Superion Indirect Decompression System (Vertiflex, Carlsbad, CA USA). Perioperative and clinical data were captured via a registry for patients treated with IPD for LSS with intermittent neurogenic claudication. Seventy-five physicians at 53 clinical sites in the US participated. Outcomes included intraoperative blood loss, procedural time, leg and back pain severity, self-defined functional objective, and patient satisfaction at 3 weeks, 6 and 12 months. PATIENT SAMPLE To date, 722 patients have undergone IPD and enrolled in the PRESS registry with a mean age of 73.0 ± 10.7 years including 379 females (53%). The maximum number of patients providing pain severity data was 603, 521, 184 and 53 at baseline, 3 weeks, 6 and 12 months, respectively. OUTCOME MEASURES Patient-reported outcomes included leg and back pain severity by 100 mm Visual Analog Scale prior to IPD as well as at 3 weeks, 6 and 12 months, postoperatively. At each follow-up interval, patients were also asked to indicate the extent to which they had achieved their Self-Defined Functional Objective, on a 1 to 5 scale, with 1 indicating no progress at all, and 5 indicating complete achievement. Additionally, patient satisfaction with IPD was queried as satisfied, somewhat satisfied, somewhat dissatisfied, or dissatisfied. Treatment approval with IPD was characterized as definitely yes, probably yes, probably not or definitely not with respect to whether the patient would repeat the treatment. METHODS Perioperative and clinical data were captured via a registry for patients treated with IPD for LSS with intermittent neurogenic claudication. RESULTS To date, 722 patients have undergone IPD and enrolled in this registry with a mean age of 73.0 ± 10.7 years including 379 females (53%). Average intraoperative blood loss was 6.1 ± 7.7 mL; median operative duration was 39.0 minutes (range: 7.0 to 210.0 mins). Mean leg pain severity decreased from 67.3 ± 26.5 mm preoperatively to 28.7 ± 33.0 mm at 12 months, reflecting an overall 57% improvement. Corresponding responder rates were 64% (335 of 521), 61% (113 of 184) and 66% (35 of 53) at 3 weeks, 6 and 12 months, respectively. Back pain severity improved similarly from 67.9 ± 25.9 mm preoperatively to 28.6 ± 31.3 mm at 12 months (58% improvement); 12-month responder rate of 64% (34 of 53). Functional objective responder rates were 63%, 67% and 81% at 3 weeks, 6 and 12 months, respectively. For patient satisfaction at 3 weeks, 6 and 12 months, 89%, 84%, and 91% were satisfied or somewhat satisfied with their treatment and 91%, 80%, and 87% would definitely or probably undergo the same treatment again. In a phone survey, the rate of revision or reoperation was 4% (21 of 517). CONCLUSIONS These registry findings support the clinical adoption of IPD in patients considering minimally-invasive options to manage chronically recalcitrant LSS symptoms. FDA DEVICE/DRUG STATUS Superion Indirect Decompression System (Approved for this indication).