Clinical evaluation of the preliminary safety and effectiveness of a minimally invasive interspinous process device APERIUS(®) in degenerative lumbar spinal stenosis with symptomatic neurogenic intermittent claudication.

PURPOSE: New interspinous process decompression devices (IPDs) provide an alternative to conservative treatment and decompressive surgery for patients with neurogenic intermittent claudication (NIC) due to degenerative lumbar spinal stenosis (DLSS). APERIUS(®) is a minimally invasive IPD that can be implanted percutaneously. This multicentre prospective study was designed to make a preliminary evaluation of safety and effectiveness of this IPD up to 12 months post-implantation.

METHODS: After percutaneous implantation in 156 patients with NIC due to DLSS, data on symptoms, quality of life, pain, and use of pain medication were obtained for up to 12 months.

RESULTS: Early symptom and physical function improvements were maintained for up to 12 months, when 60 and 58 % of patients maintained an improvement higher than the Minimum Clinically Important Difference for Zurich Claudication Questionnaire (ZCQ) symptom severity and physical function, respectively. Leg, buttock/groin, and back pain were eased throughout, and the use and strength of related pain medication were reduced. Devices were removed from 9 % of patients due to complications or lack of effectiveness.

CONCLUSIONS: Overall, in a period of up to 12 months follow-up, the safety and effectiveness of the APERIUS(®) offered a minimally invasive option for the relief of NIC complaints in a high proportion of patients. Further studies are underway to provide insight on outcomes and effectiveness compared to other decompression methods, and to develop guidance on optimal patient selection.