Safety of autologous nucleus pulposus cell transplantation with fibrin glue following endoscopic discectomy in chronic low back pain: a preliminary phase I trial

Intradiscal cell transplantation has been proposed as a minimally invasive therapeutic modality in chronic low back pain (CLBP) and may prevent future recurrence after surgical procedures. Since nucleus pulposus (NP) cells with the capability to synthesize appropriate extracellular matrix and withstand the pathological microenvironment of degenerative discs could be more practical in CLBP management. five patients with CLBP were enrolled and underwent the intradiscal injection of autologous NP cells after endoscopic therapeutic discectomy. They were followed up for 24 months by the evaluation of clinical measurements and magnetic resonance imaging (MRI). The primary outcome, safety assessment, was evaluated by recording any complications of surgery or NP cell transplantation during 24 months follow-up. Neither adverse events (AEs) nor serious adverse events (SAEs) were reported. Visual analogue scale (VAS), Oswestry disability index (ODI), and MRI were assessed as secondary outcomes. Reduction of ODI and VAS scores in all five patients indicated improvement in CLBP. Moreover, a comparison of MRI findings between the baseline and endpoint demonstrated improvement in disc protrusion status, less bulging, and more hydration. According to these promising results and MRI findings after two years follow-up, intradiscal injection of NP cells after endoscopic discectomy seems safe and could be considered as an effective therapeutic method in CLBP with no recurrence. Iranian registry of clinical trials (IRCT): IRCT20080728001031N35; Registration Date: 08/10/2022.