Long-term results of percutaneous lumbar decompression mild(®) for spinal stenosis

Lumbar spinal stenosis (LSS) generally occurs from a combination of degenerative changes occurring in the lumbar spine. These include hypertrophy of ligamentum flavum, facet joint arthritic changes and bulging of the intervertebral disk. Spinal stenosis leads to compression of the lumbar neural elements (cauda equina), which manifests as low back and leg pain especially on standing and walking known as "neurogenic claudication." Current treatment options for LSS are varied. Conservative management, including physical therapy with/without epidural steroid injections, may be adequate for mild stenosis. Surgical decompression is reserved for severe cases and results in variable degrees of success. Patients with moderate-to-severe LSS having ligamentum flavum hypertrophy as a key contributor are generally inappropriately treated or undertreated. This is due to ineffectiveness of conservative therapy and possibility that major surgical compression might be too aggressive. Percutaneous decompression offers a possible solution for this patient population.

One-year follow-up study was conducted at 11 U.S. sites. Study cohort included 58 mild(®) percutaneous decompression patients who underwent 170 procedures, the majority treated bilaterally at one or two lumbar levels. Outcome measures included the visual analog scale (VAS), Oswestry Disability Index (ODI), Zurich Claudication Questionnaire (ZCQ), and SF-12v2(®) Health Survey.

No major mild(®) device or procedure-related complications were reported. One-year data showed significant reduction of pain as measured by VAS. Improvement in physical functionality, mobility, and disability was significant as measured by ZCQ, SF-12v2, and ODI.

At 1 year this 58-patient cohort demonstrated continued excellent safety profile of the mild(®) procedure and equally important, showed long-term pain relief and improved functionality.