The MILD Procedure for Spinal Stenosis: What You Need to Know

If you've been told you have spinal stenosis with neurogenic claudication — the leg pain and cramping that comes with walking and gets better when you sit — the MILD procedure may be the minimally invasive solution that lets you walk farther, stand longer, and live more fully without the risks of traditional surgery.

Neurogenic Claudication: The Classic Picture

Patients with lumbar spinal stenosis describe a very characteristic pattern:

• They can walk a block before leg pain, heaviness, or cramping sets in
• Sitting down or bending forward (like over a shopping cart) quickly relieves symptoms
• Standing in line is more painful than walking
• Bilateral symptoms (both legs) are common

This pattern occurs because the spinal canal narrows further in extension (standing upright) and opens in flexion (bending forward). Any treatment that mechanically keeps the spine slightly flexed at the stenotic level will provide relief.

What Causes This? Thickened Ligamentum Flavum

One of the primary causes of lumbar spinal stenosis — particularly in older patients — is hypertrophy (thickening) of the ligamentum flavum, the ligament that lines the inside of the spinal canal. This ligament can double or triple in thickness over time, encroaching on the space available for the spinal cord and nerve roots.

How MILD Works

The MILD procedure removes small pieces of the thickened ligamentum flavum through a tiny tube (no open incision) — restoring canal space from the inside.

Technical details:

• Incision: 1–2 mm (no stitches)
• Anesthesia: Local with light sedation
• Setting: Outpatient
• Duration: 30–45 minutes
• Recovery: Home same day; resume activities in days

No fusion, no implants, no removal of significant bone structure.

The Evidence

The ENCORE randomized controlled trial — in which Dr. Rubin was a principal investigator — compared MILD to continued epidural steroid injections for neurogenic claudication. Results:

• Significantly greater improvement in walking tolerance with MILD vs. ESI
• Improved pain and function scores maintained at 2-year follow-up
• No serious adverse events attributable to the procedure

Who Is a Good Candidate?

You're likely a candidate if:

• You have lumbar spinal stenosis with neurogenic claudication confirmed on MRI
• Your symptoms improve when you bend forward or sit
• MRI shows ligamentum flavum hypertrophy (thickening ≥2.5 mm) at the stenotic level
• You've tried conservative treatment and want to avoid open surgery

MILD is covered by Medicare and most commercial insurance.

Getting Started

Call 516-492-3100 to discuss whether the MILD procedure is appropriate for your lumbar stenosis. Bring your lumbar MRI if you have one.