Purpose: The purpose of this study is to assess safety and feasibility of intradiscal bone marrow concentrate (BMC) injections to treat low back discogenic pain as an alternative to surgery with three year minimum follow-up.
Methods: A total of 26 patients suffering from degenerative disc disease and candidates for spinal fusion or total disc replacement surgery were injected with 2 ml autologous BMC into the nucleus pulposus of treated lumbar discs. A sample aliquot of BMC was characterized by flow cytometry and CFU-F assay to determine progenitor cell content. Improvement in pain and disability scores and 12 month post-injection MRI were compared to patient demographics and BMC cellularity.
Results: After 36 months, only six patients progressed to surgery. The remaining 20 patients reported average ODI and VAS improvements from 56.7 ± 3.6 and 82.1 ± 2.6 at baseline to 17.5 ± 3.2 and 21.9 ± 4.4 after 36 months, respectively. One year MRI indicated 40% of patients improved one modified Pfirrmann grade and no patient worsened radiographically. Cellular analysis showed an average of 121 million total nucleated cells per ml, average CFU-F of 2713 per ml, and average CD34+ of 1.82 million per ml in the BMC. Patients with greater concentrations of CFU-F (>2000 per ml) and CD34+ cells (>2 million per ml) in BMC tended to have significantly better clinical improvement.
Conclusions: There were no adverse events related to marrow aspiration or injection, and this study provides evidence of safety and feasibility of intradiscal BMC therapy. Patient improvement and satisfaction with this surgical alternative supports further study of the therapy.
Keywords: Bone marrow concentrate; Degenerative disc disease; Intradiscal injection; Mesenchymal stem cells.