Minimally Invasive Lumbar Decompression (MILD)

What does MILD treat?

MILD is used to treat narrowing in the lower part of the spinal canal, or lumbar spinal stenosis (LSS). LSS is a degenerative condition that typically worsens with age and can cause pain, numbness, and tingling in the lower extremities. Patients also describe symptoms of neurogenic claudication (i.e., pain, numbness, and heaviness in the legs with standing). LSS can be treated with physical therapy, non-opioid pain medication, and lumbar epidural steroid injections. If these treatments do not adequately relieve pain, MILD, a minimally invasive procedure, might be an option for some patients before considering spine surgery.

Why opt for the MILD?

MILD is a brief outpatient procedure with low complication risk and quick recovery. Performed through a small incision, it allows patients to resume daily activities quickly. MILD effectively treats the root cause of LSS by addressing narrowing, providing pain relief and improved functionality. It can significantly reduce pain during activities like walking and standing, making it a viable option for treating LSS with minimal surgical risks and effective results in specific patients with hypertrophied ligamentum flavum.

The Procedure

1. Prior to the day of the procedure, the location of stenosis on the spine is identified via magnetic resonance imaging (MRI).
2. On the day of the procedure, the patient lies face-down on the operating table and the back is cleaned with antimicrobial solution.
3. Local anesthetic is administered. The patient receives light to moderate sedation.
4. Location of stenosis on the spine is again confirmed via real-time x-rays.
5. An incision smaller than the size of a baby aspirin is made on the skin and a thin portal is inserted through the incision to the spine.
6. Surgical instruments are guided in through the portal, and with the help of real-time x-rays, the instruments are used to remove part of the laminar bone causing stenosis. Part of the ligamentum flavum, which is a special spinal ligament that supports the laminar bones, is also partly removed with some fatty tissue.
7. X-ray will confirm decompression, after which the portal and surgical instruments are removed from the incision.
8. The skin is then covered with a bandage.
9. The patient is then observed in the recovery area.
10. After a neurological exam, the patient is discharged and free to go home.

Words to Know

Ligament – fibrous connective tissue that attaches bones together.

Ligamentum flavum – ligament in spine that attaches lamina (bones originating from vertebrae) together.

Stenosis – narrowing of the spinal canal which can lead to compression of the spinal cord or nerve roots sand subsequently lead to pain and functional dysfunction.

References

1. Staats PS, et al. Long-Term Safety and Efficacy of Minimally Invasive Lumbar Decompression Procedure for the Treatment of Lumbar Spinal Stenosis With Neurogenic Claudication: 2-Year Results of MiDAS ENCORE. Reg Anesth Pain Med. 2018.
2. Benyamin RM, et al. MILD® Is an Effective Treatment for Lumbar Spinal Stenosis with Neurogenic Claudication: MiDAS ENCORE Randomized Controlled Trial. Pain Physician. 2016.
3. Hagedorn JM, et al. The incidence of lumbar spine surgery following Minimally Invasive Lumbar Decompression and Superion Indirect Decompression System for treatment of lumbar spinal stenosis: a retrospective review. Pain Pract. 2022.
4. Mekhail N, et al. The durability of minimally invasive lumbar decompression procedure in patients with symptomatic lumbar spinal stenosis: Long-term follow-up. Pain Pract. 2021.