Randomized, Comparative-Effectiveness Study of Intradiscal Autologous Stem Cells Versus Intradiscal Corticosteroid for Chronic Discogenic Low Back Pain

Discogenic pain accounts for 20-45% of cases of mechanical low back pain and is more common in younger and middle-aged adults (Manchikanti, 2000). Diagnosis can be made on the basis of a combination of symptoms and exam findings, imaging, lack of improvement with facet injections sacroiliac injections and epidural steroid injections, and concordant pain relief with provocative discography. Surgical treatments may include spinal fusion or artificial disc replacement. A systematic review of fusion to non-surgical treatment in patients with more than one year of moderate to serve low back pain found only a 35% improvement in the surgical group and 20% improvement in the non-surgical group. Various injectables, including corticosteroids and tumor necrosis factor, have been investigated for the treatment of discogenic low back pain. In a study of 120 patients randomized to receive intradiscal corticosteroid or saline, Cao et al found a significant improvement in pain and function at 3 and 6 months in the corticosteroid group. In Cohen’s placebo-controlled study of 36 patients, intradiscal etanercept did not seem to improve outcomes. There is growing interest in the use of cell therapy, primarily mesenchymal stem cells, for the regeneration of intervertebral disc cells thought to contribute to disc degeneration and discogenic pain. Pettine treated 26 patients with intradiscal autologous mesenchymal stem cells and reported an average percentage of visual analog score reduction of 64%, 64%, and 57% and Oswestry Disability Index (ODI) reduction of 58%, 55%, and 57% at 3, 6, and 12 months respectively. There are other published case series showing similar benefit, but there are no controlled trials evaluating stem cells for discogenic pain. It is not clear whether the stem cells, extracellular matrix, or other factors contribute to the improvement observed in these cases.