Interspinous Spacer

What Is an Interspinous Spacer?

An interspinous spacer is a small implant inserted between the bony projections (spinous processes) of two adjacent lumbar vertebrae. It acts like a wedge, holding the spine in a slightly flexed position that widens the spinal canal. This minimally invasive approach can dramatically reduce the pressure on nerves responsible for leg pain, numbness, and difficulty walking.

How It Works

•The device is inserted through a small incision and seated between the spinous processes, typically at the L3–L5 level.

•By maintaining slight forward flexion, the implant increases the diameter of the spinal canal and foramina, reducing nerve compression.

•No bone removal or general anesthesia is required, making it a lower-risk alternative to open decompression surgery for appropriate candidates.

What to Expect During the Procedure

•Preparation: The skin is sterilized and local anesthetic is administered; light sedation is typically used.

•Duration: The procedure generally takes 30–45 minutes.

•Incision: A small incision (1–2 cm) is made in the midline of the lower back.

•Guidance: Fluoroscopic imaging confirms correct device placement.

•Same-day recovery: Most patients walk the same day and are discharged within a few hours.

Conditions Treated

•Lumbar spinal stenosis (narrowing of the spinal canal)

•Neurogenic claudication (leg pain/cramping when standing or walking)

•Degenerative disc disease with stenosis

•Spondylolisthesis (grade 1)

•Facet joint arthropathy contributing to stenosis

Who Is a Good Candidate?

Adults over 50 with moderate-to-severe lumbar spinal stenosis who experience relief when sitting or bending forward — and who have not responded adequately to conservative care — are typically the best candidates. Those who need to avoid major surgery due to age or health conditions may also benefit.

Recovery & Results

Most patients resume light activity within a few days and experience noticeable improvement in walking distance and leg symptoms within 1–2 weeks. Clinical studies show meaningful relief in neurogenic claudication symptoms for many patients, with benefits durable at 2-year follow-up for appropriate candidates. Routine imaging follow-up is typically scheduled at 6 weeks.

Frequently Asked Questions

How is this different from spinal fusion?

An interspinous spacer does not fuse vertebrae together, preserving more natural motion. It is also placed through a much smaller incision than traditional fusion surgery.

Can the spacer be removed if needed?

Yes. Most interspinous spacer devices are removable and can be taken out or revised if needed, and the patient can still proceed to open surgery if necessary.

Will I feel the implant?

The device is seated deep in the spine between bone. Most patients are not aware of its presence once initial healing is complete.