By Marc Darrow, MD, JD | Stem Cell Institute

A patient may arrive with an MRI showing a bulging disc, arthritis, and “severe” lumbar spinal stenosis. Sometimes the main problem is pain across the low back. Sometimes walking brings on pain and heaviness in the buttocks and legs. Those two presentations need different questions and may need different treatments.

On an episode of Living Pain-Free, a caller described severe spinal canal narrowing at more than one level, leg and buttock pain, a previous discectomy complicated by infection, and a recommendation for a minimally invasive decompression procedure. He wanted to know whether platelet-rich plasma (PRP) could help. The answer depends on what is driving his symptoms. PRP cannot physically widen the spinal canal, but an evaluation may identify another treatable source of pain in addition to the narrowing. We would not use an injection to delay needed decompression. Read the program discussion.

What is lumbar spinal stenosis?

Stenosis means narrowing. The lumbar spine is the lower back. Its central canal contains the nerve roots that travel toward the legs, while the smaller openings at the sides—the foramina—allow individual nerve roots to exit. With age or injury, changes in the discs, facet joints, and spinal ligaments can reduce the room available to those nerves.

Central canal stenosis and foraminal stenosis are descriptions of anatomy, not complete diagnoses of a person’s pain. Symptoms may include low back pain, pain or heaviness in the buttocks and legs, tingling, or weakness. A characteristic pattern, called neurogenic claudication, worsens with standing or walking and improves when the person sits or bends forward. Many people describe being able to walk farther when leaning on a shopping cart. Other conditions, including vascular disease, hip problems, and nerve disorders, can produce some similar complaints. (1)

Does “severe” stenosis on MRI mean surgery is inevitable?

No. MRI is useful for locating and describing narrowing, but we also need to know whether its level and side fit the symptoms. We ask how far the patient can walk, what relieves the pain, whether there is progressive weakness, and how symptoms affect daily life. We examine strength, sensation, reflexes, gait, and possible hip or sacroiliac sources. Imaging can help plan a procedure when appropriate; the report alone cannot decide whether surgery or an injection is the best next step.

This point applies to discs as well. In a review of imaging studies involving 3,110 people without symptoms, estimated disc degeneration increased with age and appeared in 37% of people at age 20 and 96% at age 80. That finding does not make a symptomatic herniation unimportant. It shows why we compare imaging with a person’s actual pain pattern and examination. (2)

Can a herniated disc shrink without surgery?

Sometimes. A disc has an outer ring, the annulus fibrosus, surrounding softer material. Material that has pushed out can occasionally become smaller over time. A systematic review reported regression on follow-up imaging in 96% of sequestered herniations, 70% of extrusions, 41% of protrusions, and 13% of bulges in studies suitable for those estimates. A sequestered fragment has separated from the disc. The 96% figure concerns imaging changes in one selected category; it does not mean 96% of all patients recovered. That review excluded people with spinal stenosis and cannot predict whether a narrowed canal will improve. (3)

A patient with a disc herniation, a patient with stenosis from thickened ligaments and enlarged joints, and a patient with both conditions may therefore have different options. We discuss the actual anatomy and neurologic findings instead of promising that all “back pain” will respond the same way.

Which nonsurgical treatments are reasonable to try first?

When there is no urgent neurologic concern, many people begin with activity modification, a guided exercise or physical therapy program, and medication when appropriate. The goals are to improve walking, build strength, and manage symptoms while preserving useful activity. Some patients benefit from learning positions and pacing strategies that make walking more tolerable. Bracing may help selected patients, although it is not a structural cure.

An epidural steroid injection may offer short-term symptom relief for some patients, but lasting benefit for spinal stenosis has not been established. The decision should take account of medical conditions, prior procedures, risks, and what the patient hopes the injection will accomplish. A 2022 clinical review described physical therapy and other conservative care as common initial approaches and noted that some patients remain stable or improve without an operation. It also found that appropriately selected patients with ongoing, limiting symptoms may benefit from decompression. (4)

At Stem Cell Institute, our evaluation also asks whether pain is coming from another structure alongside the stenosis—for example, a facet joint, disc, hip, or sacroiliac region. Identifying a second pain source can change the plan, but it does not mean the spinal narrowing is irrelevant. In a patient with classic walking-related leg symptoms and matching MRI compression, we take the nerve problem seriously.

Can PRP treat spinal stenosis?

PRP is prepared by concentrating platelets from a patient’s own blood. Investigators have studied PRP injections for specific spinal pain patterns, including some lumbar nerve-root symptoms, facet joint pain, and pain thought to arise from a disc. These targets are different. PRP does not remove bone, reduce a thickened ligament, or enlarge a stenotic canal. If we discuss it for a separately diagnosed source of pain, we explain that target and the evidence for that indication.

A 2023 systematic review included randomized and nonrandomized studies of PRP for several kinds of low back pain and reported encouraging results overall. Its pooled topic was low back pain, not proof of benefit for severe central canal stenosis. Different injection sites, preparations, comparators, and follow-up periods limit how confidently any result can be applied to one patient. (5)

A 2026 review restricted its analysis to 13 randomized trials of PRP and cell-based therapies for degenerative spinal conditions. It reported more favorable intermediate-term results for PRP in selected lumbar radicular and facet pain trials, while intradiscal PRP findings were mixed. The review did not establish PRP as a way to reverse the anatomy of lumbar spinal stenosis. It also reported a serious disc infection after an intradiscal PRP procedure, underscoring the need to discuss procedural risks. (6)

What about bone marrow concentrate and “stem cell therapy”?

Bone marrow aspirate concentrate, or BMAC, is made by collecting and concentrating a sample of the patient’s own bone marrow. It contains a mixture of cells and other components; it is not a purified or laboratory-cultured stem cell product. Research on BMAC and cell preparations for disc-related pain remains developing. In the 2026 randomized-trial review, autologous BMAC and mesenchymal cell preparations did not outperform sham treatment on primary pain and function outcomes in the trials discussed. An investigational donor-derived mesenchymal precursor cell product had more promising findings in a different trial, but that is not interchangeable with a patient’s own BMAC and is not proof of benefit for spinal stenosis. (6)

We would not promise that BMAC rebuilds a disc, opens the spinal canal, or prevents a needed operation. For a patient considering an injection, the important questions are which tissue is being treated, what preparation is used, what human evidence supports that use, and what outcome is realistically expected.

Does Wharton’s jelly have a proven role in lumbar stenosis?

Wharton’s jelly is tissue from the umbilical cord. Interest in its biological properties does not establish that an injected product treats low back pain or decompresses nerves. A clinical trial registration describes a proposed study; it is not itself evidence that the treatment works. We would not recommend a cord-derived product on the strength of a marketing claim or an individual testimonial.

The FDA warns that umbilical cord tissue products, Wharton’s jelly, and other regenerative products marketed for orthopedic or pain conditions may require approval and that unapproved products have been associated with serious harms. Product-specific regulatory status should be checked before any patient considers such a treatment. (7)

When is surgery the better choice?

A surgeon may recommend decompression when leg-dominant pain, impaired walking, or neurologic symptoms continue despite appropriate nonsurgical care and match the site of compression. The procedure aims to make more space for nerves. Some patients also have instability or another reason to discuss fusion, but fusion has different risks and is not automatically required with decompression. The choice should be individualized, particularly after prior spine surgery or infection. (4)

The caller’s past infection matters. It deserves a careful review of records, present symptoms, and imaging before further injections or surgery. We would discuss what the proposed minimally invasive decompression procedure is intended to address and whether his walking-related symptoms fit the narrowed levels. A second surgical opinion can be useful if the benefits and risks remain unclear.

Seek urgent medical evaluation for new bladder or bowel dysfunction, numbness around the groin, rapidly worsening leg weakness, fever with severe back pain, or new severe pain after major trauma. Those symptoms should not wait for a regenerative medicine consultation.

This article is educational and does not replace an individual medical evaluation.

References

  1. Webb CW, Aguirre K, Seidenberg PH. Lumbar Spinal Stenosis: Diagnosis and Management. Am Fam Physician. 2024;109(4):350–359.
  2. Brinjikji W, Luetmer PH, Comstock B, et al. Systematic literature review of imaging features of spinal degeneration in asymptomatic populations. AJNR Am J Neuroradiol. 2015;36(4):811–816.
  3. Chiu CC, Chuang TY, Chang KH, Wu CH, Lin PW, Hsu WY. The probability of spontaneous regression of lumbar herniated disc: A systematic review. Clin Rehabil. 2015;29(2):184–195.
  4. Katz JN, Zimmerman ZE, Mass H, Makhni MC. Diagnosis and Management of Lumbar Spinal Stenosis: A Review. JAMA. 2022;327(17):1688–1699.
  5. Machado ES, Soares FP, de Abreu EV, et al. Systematic Review of Platelet-Rich Plasma for Low Back Pain. Biomedicines. 2023;11(9):2404.
  6. Zhang RE, Aurangzeb A, Sirisena D. Platelet-rich plasma and stem cell therapies for spondylosis: a systematic review of randomized controlled trials. Eur Spine J. Published online May 16, 2026. doi:10.1007/s00586-026-09997-9.
  7. U.S. Food and Drug Administration. Important Patient and Consumer Information About Regenerative Medicine Therapies. June 3, 2021.