Minimally Invasive Lumbar Decompression (MILD)

OVERVIEW

What MILD is and how it works

Lumbar spinal stenosis is a narrowing of the spinal canal in the lower back. One common cause is a thickened ligamentum flavum — a ligament inside the canal that, with age, can enlarge and crowd the nerves. That pressure produces the hallmark symptoms of stenosis: aching, heaviness, or cramping in the legs and buttocks that worsens with standing or walking and eases when you sit or lean forward.

The MILD procedure (minimally invasive lumbar decompression) is a percutaneous treatment that targets this specific problem. Working through a port about the size of a small straw and using continuous X-ray guidance, the physician removes small pieces of the overgrown ligament and a thin portion of bone. Decompressing the canal gives the crowded nerves more room. Because everything is done through a tiny opening, there is no open surgery, no fusion, and — importantly — no implant or hardware left in the spine.

CONDITIONS

Conditions MILD can help

MILD is used for patients whose imaging shows central canal stenosis driven by ligamentum flavum hypertrophy, particularly when conservative care — such as physical therapy, medication, or epidural steroid injections — has not provided lasting relief.

YOUR VISIT

What to expect with MILD

MILD is performed on an outpatient basis at Burnside Surgery Center, our associated ambulatory surgery center in Gresham, serving patients throughout Gresham, Portland, and the surrounding Oregon communities. Continuous image guidance is central to the procedure — it lets the physician work precisely within the spinal canal through a very small entry point. Your care team will give you recovery and follow-up instructions tailored to you.

QUESTIONS

Frequently asked questions about MILD

Is anything left inside my spine?

No. Unlike procedures that place a spacer or stimulator, MILD removes a small amount of thickened ligament and bone and leaves no implant or hardware behind.

Is MILD the same as open back surgery?

No. It is a percutaneous, minimally invasive procedure done through a tiny opening using X-ray guidance, rather than a traditional open operation. There is no large incision and no spinal fusion.

Will I be put fully to sleep?

Typically no. MILD is usually performed with local anesthetic and light sedation so you are comfortable while remaining safely monitored. Your physician will review the anesthesia plan with you beforehand.

What if my stenosis has another cause?

MILD is designed for narrowing caused by a thickened ligamentum flavum. If your imaging points to a different cause, your physician will discuss other options that may be a better fit for your situation.

LEARN MORE

Related procedures and next steps