Back pain is a major cause of disability globally. Despite its common occurrence and impact, we don't yet have a universally accepted treatment that fully restores the function of worn-out spinal discs. Recently, stem cells have shown promise as a potential therapy for regenerating discs affected by degenerative disc disease.
As discs get older, they undergo changes in both their strength and structure. These changes happen because the body's cells react to wear and tear. The aging process causes more tears in the tissue, creates small particles, and leads to the growth of new blood vessels, starting from the outer part of the disc and moving inward. With age, the inner part of the disc, called the nucleus pulposus (NP), becomes less jelly-like and more fibrous. This shift results in the development of gaps that go through the outer part of the disc, causing a gradual decrease in disc size and overall height .
Other changes related to aging involve the hardening and thinning of the disc's outer edges, the formation of tiny fractures in the nearby bone, bone thickening, and a significant decrease in blood vessels in the disc's cartilage edges. The reduced blood supply to these edges worsens the shortage of nutrients, leading to less oxygen, more waste accumulation, and the creation of an acidic environment. This compromised setting affects the disc cells' ability to make and support the extracellular matrix (ECM)]. In the end, these changes in the ECM contribute to the degeneration of the disc.
Commonly employed treatments for disc degeneration include:
Conservative Management:
Physical therapy to improve strength and flexibility.
Pain medications and anti-inflammatory drugs.
Lifestyle modifications, such as weight management and avoiding prolonged sitting.
Interventional Procedures:
Epidural steroid injections to reduce inflammation and alleviate pain.
Facet joint injections for pain relief.
Radiofrequency ablation to disrupt nerve signals and reduce pain.
Surgical Options:
Discectomy: Removal of part of a disc.
Spinal fusion: Joining two or more vertebrae together.
Artificial disc replacement: Replacement of a damaged disc with an artificial one.
As of now, there is a lack of definitive solutions for disc degeneration.
According to the study titled "One-year Outcomes of Surgical versus Non-surgical Treatments for Discogenic Back Pain: A Community-based Prospective Cohort Study," authored by Sohail K. Mirza, MD, MPH, Richard A. Deyo, MD, MPH, Patrick J. Heagerty, PhD, Judith A. Turner, PhD, Brook I. Martin, PhD, and Bryan A. Comstock, MS. The study was conducted as a community-based prospective cohort study and is available under the publication information provided below
The study looked at treatments for discogenic back pain and found that both surgery and non-surgical approaches had modest outcomes. Patients seeking surgery had moderate pain and disability levels, and those who had surgery along with other treatments showed some improvement compared to those continuing non-surgical care. However, only a third of surgical patients achieved a successful outcome, and surgery was associated with increased restrictions and opioid use. Non-surgical care, often not following guidelines, showed minimal improvement. The study suggests that even basic conservative care may lead to significant improvements, highlighting the challenges of treating discogenic back pain.
Possible complication from surgery
Infection:
Infections can occur at the surgical site or in the spine itself.
Bleeding:
Excessive bleeding during or after surgery can occur, requiring further intervention.
Nerve Injury:
Nerve damage can lead to sensory or motor deficits. The risk depends on the surgery's complexity and proximity to nerves.
Dural Tear or Cerebrospinal Fluid Leak:
Damage to the dura (the covering of the spinal cord) can lead to cerebrospinal fluid leakage.
Hardware-related Issues:
Hardware, such as screws or plates, may break or loosen over time.
Blood Clots:
Deep vein thrombosis (DVT) or pulmonary embolism can occur.
Failed Fusion:
Fusion surgeries aim to join two vertebrae; however, fusion may not occur successfully in some cases.
Persistent Pain:
Surgery may not always alleviate pain, and some patients may experience persistent or new pain.
Anesthetic Complications:
Complications related to anesthesia, such as allergic reactions or respiratory issues.
Instrumentation Issues:
Problems with implanted devices, such as rods or screws.
How about cell therapy ?
According to the study published in the International Journal of Molecular Sciences on May 17, 2023, with the title "Potential Role for Stem Cell Regenerative Therapy as a Treatment for Degenerative Disc Disease and Low Back Pain: A Systematic Review," conducted by Soufi et al., the authors explored the potential of stem cell regenerative therapy in addressing degenerative disc disease and low back pain.
A clinical trial is currently looking for participants to test the safety and effectiveness of using human umbilical cord mesenchymal stem cells (hUC-MSCs) for treating lumbar degenerative disc disease (DDD) . In this trial, twenty individuals with lumbar DDD, diagnosed with lumbar disc herniation will be enrolled. The patients will receive an immediate injection of hUC-MSCs. The main measure of success involves observing changes in lumbar disc MRI signaling values over 3, 6, and 12 months, compared to the baseline. Secondary outcomes will include assessments using various tools disc height index from an X-ray, and the location of the herniated nucleus pulposus (HNP) from an MRI. Participants will be monitored for any treatment-related adverse events (TEAEs) and serious adverse events (SAEs) for a period of 12 months. Preclinical studies have shown that hUBC MSCs can survive and take on a chondrocyte-like phenotype when injected into the intervertebral disc (IVD).
From a clinical standpoint, identifying suitable candidates for the treatment and objectively assessing their improvement poses challenges due to the multifactorial and complex nature of back pain. While height restoration in a degenerative disc could be a potential indicator of improvement, it has limitations as pain relief has been observed without disc height restoration. Not all back pain is discogenic, and stem cell therapy is often considered for back pain linked to degenerative disc disease.