Background: Several cell-based therapies have been proposed in recent years the management of low back pain, including the injection of medicinal signaling cells or mesenchymal stem cells (MSCs) and platelet-rich plasma (PRP). However, there is only emerging clinical evidence to support their use at this time.
Objective: To assess the effectiveness of MSCs or PRP injections in the treatment of low back and lower extremity pain.
Study design: A systematic review and metaanalysis of the effectiveness of PRP and MSCs injections in managing low back and lower extremity pain.
Data sources: PubMed, Cochrane Library, US National Guideline Clearinghouse, prior systematic reviews, and reference lists. The literature search was performed from 1966 through June 2018.
Study selection: Randomized trials, observational studies, and case reports of injections of biologics into the disc, epidural space, facet joints, or sacroiliac joints.
Data extraction: Data extraction and methodological quality assessment were performed utilizing Cochrane review methodologic quality assessment and Interventional Pain Management Techniques - Quality Appraisal of Reliability and Risk of Bias Assessment (IPM-QRB) and Interventional Pain Management Techniques - Quality Appraisal of Reliability and Risk of Bias Assessment for Nonrandomized Studies (IPM-QRBNR). The evidence was summarized utilizing principles of best evidence synthesis on a scale of 1 to 5.
Data synthesis: Twenty-one injection studies met inclusion criteria. There were 12 lumbar disc injections, 5 epidural, 3 lumbar facet joint, and 3 sacroiliac joint studies RESULTS: Evidence synthesis based on a single-arm metaanalysis, randomized controlled trials (RCTs), and observational studies, disc injections of PRP and MSCs showed Level 3 evidence (on a scale of Level I through V). Evidence for epidural injections based on single-arm metaanalysis, a single randomized controlled trial and other available studies demonstrated Level 4 (on a scale of Level I through V) evidence. Similarly, evidence for lumbar facet joint injections and sacroiliac joint injections without metaanalysis demonstrated Level 4 evidence (on a scale of Level I through V).
Limitations: Lack of high quality RCTs.
Conclusion: The findings of this systematic review and single-arm metaanalysis shows that MSCs and PRP may be effective in managing discogenic low back pain, radicular pain, facet joint pain, and sacroiliac joint pain, with variable levels of evidence in favor of these techniques.
Key words: Chronic low back pain, regenerative therapy, medicinal signaling or mesenchymal stem cells, platelet-rich plasma, disc injection, lumbar facet joint injections, sacroiliac joint injections.