Safety and Feasibility of Intradiscal Autologous Bone Marrow Aspirate Concentrate at the Time of Lumbar Microdiscectomy: A Prospective Pilot Study

Lumbar microdiscectomy improves pain and disability but does not restore disc biology, and same-site recurrence can occur. Intradiscal autologous bone marrow aspirate concentrate (BMAC) has growing preclinical support, but human safety data are limited. To evaluate intradiscal BMAC safety and feasibility at lumbar microdiscectomy. Patients underwent lumbar microdiscectomy and 1 mL intradiscal autologous BMAC with 1-year follow-up. Primary outcomes were procedure-related complications, readmissions, reoperations, and same-site recurrence; secondary outcomes were Oswestry Disability Index (ODI) and Numeric Rating Scale (NRS) for leg and back pain; exploratory quantitative magnetic resonance imaging (MRI; T 1 -rho, T 2 ) screened for adverse compositional changes. 27 adults underwent lumbar microdiscectomy with concurrent intradiscal BMAC injections. No intraoperative or postoperative injection-related complications occurred. Same-site recurrence occurred in 1/27 (3.7%) and was managed without reoperation. Patient-reported outcome measures (PROMs) were completed by 18/27 (67%), and qMRI was obtained in 16, including 6 with complete imaging through 1 year. Among patients with completed PROMs, mean ODI, NRS-leg, and NRS-back improved at 1 year, but the uncontrolled design precludes efficacy inference. No adverse changes in T 1 -rho or T 2 were observed through 1 year. In this single-center prospective pilot, intradiscal BMAC at the time of microdiscectomy was safe and feasible, with no injection-related harm through 1 year and one same-site recurrence. Without a control group and with incomplete follow-up, findings are preliminary safety data, not evidence of efficacy or reduced recurrence risk. These results support a multicenter study with longer follow-up and a controlled comparison group.