Platelet-rich plasma and stem cell therapies for spondylosis: a systematic review of randomized controlled trials

BACKGROUND: Spinal spondylosis - including degenerative disc disease, facet arthropathy, and stenosis - is a leading cause of chronic spinal pain. Regenerative biologics such as platelet-rich plasma (PRP), bone marrow aspirate concentrate (BMAC), and mesenchymal cell therapies are increasingly used, yet evidence remains inconsistent. This systematic review synthesizes randomized controlled trials (RCTs) evaluating biologic injections for degenerative spinal conditions. METHODS: MEDLINE, Embase, and Cochrane CENTRAL databases were searched from inception to September 22, 2025. Only RCTs evaluating PRP, BMAC, mesenchymal stem/stromal cells (MSCs), or mesenchymal precursor cells (MPCs) for degenerative spinal pain were included. Outcomes included pain, function, imaging, and adverse events. Risk of bias was assessed using Cochrane RoB 2. RESULTS: Thirteen RCTs met eligibility. For lumbar radiculopathy, four trials showed that corticosteroids provided faster early relief, but PRP produced significantly greater improvement at 3-6 months, with higher proportions achieving clinically meaningful pain and ODI reduction. In facetogenic pain, lumbar facet PRP surpassed steroids at 6 months, whereas cervical facet outcomes were similar across groups. Evidence for intradiscal PRP was mixed: one large RCT showed no benefit versus saline; smaller trials reported delayed functional gains. While autologous BMAC and MSC preparations did not demonstrate superiority over sham controls for primary pain and functional outcomes (Levi 2025, Vadalà 2025), allogeneic MPCs demonstrated significant, durable improvements in both pain and disability compared to saline through 36 months, particularly when delivered in a hyaluronic acid vehicle (Amirdelfan 2021). In contrast, a large multicenter RCT demonstrated that allogeneic MPCs significantly increased the proportion of patients achieving ≥ 10-15-point ODI improvement and durable pain reduction over 12-36 months (Amirdelfan 2021). Across all studies, adverse events were minimal, though one case of spondylodiscitis followed intradiscal PRP. CONCLUSION: PRP provides durable mid-term benefit for lumbar radiculopathy and lumbar facet pain, while intradiscal PRP, BMAC, and autologous MSCs show limited efficacy. Allogeneic MPCs are the most promising cell-based therapy but remain investigational. Standardization of biologic preparation and larger, multicenter RCTs are needed.