Background: Treatment of intermediate-stage painful degenerative disc disease is controversial, with few reliable options. Allogenic mesenchymal stem cells (MSCs)are an alternative to autologous stem cell transplantation. Allogeneic MSCs in the treatment of discogenic low back pain have some practical advantages, ranging from availability to ease of treatment in a procedure-room setting.
Objectives: To assess the efficacy and safety of allogenic MSC injection into painful lumbar intervertebral discs and associated clinical outcomes.
Study design: Retrospective observational cohort study.
Setting: Private practice.
Methods: There were 33 patients: 15 women and 18 men with an average age of 47.6 years. The patients' average follow-up was 26.88 months Patients were treated with intradiscal injection of approximately 5 million allogeneic polyclonal MSCs in 1% hyaluronic acid derived from immunoselected umbilical cord stem cells. Patients were monitored for adverse event reactions. Clinical outcomes were assessed with reductions in the reported Visual Analog Scale (VAS) for back pain, the Oswestry Disability Index (ODI) scores, and the use of the modified Macnab criteria.
Results: No patient required any additional treatments for low back pain stemming from the level treated with MSC injections. At a 2-year follow-up, the average VAS low back score reduction was 6.565 ± 1.619 and 38.333 ± 14.865 for the ODI (P < 0.001). Reported Macnab outcomes were excellent in 11 patients (33.3%), good in 19 (57.6%), and fair in 3 (9.1%).
Limitations: Our observational study is limited by patient selection, hindsight bias, and low patient numbers.
Conclusion: The results of our feasibility study suggest that the injection of allogeneic MSCs to treat patients with painful intermediate-stage degenerative disc disease has merit. No adverse reactions were observed. The authors recommend further study in a randomized prospective study setting with a placebo control group or a natural history study group of patients to solidify this research.
Keywords: degenerative intervertebral disc disease; low back pain; mesenchymal stem cells; Allogeneic.