A Randomized Placebo-Controlled Trial of Platelet Rich Plasma (PRP) Injection in a Military Population with Facet Mediated Lumbar Low Back Pain
Low back pain (LBP) is both the single most common cause of disability and the leading cause of visits to primary care doctors. Not surprisingly, the direct and indirect costs of low back pain accounts for approximately $88 billion of health care expenditure—barely trailing the cost of care for diabetes and heart disease. In order to reduce the large financial and personal cost, clinical studies must be designed to treat LBP.
Peer-reviewed literature has shown that the incidence of lumbar facet mediated pain ranges from 15-45% among patients with LBP. Some of the challenge to diagnosing facet mediated pain is based on poor correlation of abnormal imaging findings to patient’s symptoms. Not only is there a high prevalence of abnormalities on magnetic resonance imaging (MRI) of asymptomatic population, advanced imaging such as computed tomography (CT) scans fail to show an association between facet joint pain and degenerative changes seen within CT. It is due to such poor correlation of image findings to patient’s symptoms that medial branch block (MBB) has become the standard to diagnose facet joint pain.
Once facet joint pain has been diagnosed clinically, the current interventional treatment options for prolonged relief includes corticosteroid (CSI) injection of the facet joint or radiofrequency ablation of the medial branch nerves. There are variable evidence to the effectiveness of the corticosteroid injection of the lumbar facet joints, with a systemic review showing Level III evidence of trials with short term effectiveness less than 6 months. The evidence for radiofrequency ablation is more robust with Level 1 evidence for effectiveness less than 6 month and Level 2 evidence for effectiveness greater than 6 months (Manchikanti L. et al., 2015; Rajni Vekaria et al., 2016). There are also studies that have suggested similar effectiveness of intra-articular facet joint injection and radiofrequency ablation. Other clinical providers have evaluated autologous use of biological material to treat facet mediated pain including platelet rich plasma (PRP), to accelerate healing of a degenerative tissue. (Wu J et al., 2016).
Novel treatment methods for treating facet pain are sorely needed since CSI treatments have reported risks associated with injection, osteoporosis, accelerated degeneration, avascular necrosis, and suppression of endogenous corticosteroid production. Further, the long-term consequence of ongoing radiofrequency ablation treatment has not been fully elucidated. While radiofrequency ablation (RFA) temporarily denervates the medial branch that provides the sensation to the facet joint, RFA also denervates parts of paraspinal muscles, which can potentially cause weakness and further slow rehabilitation.
The use of orthobiologics and concepts behind regenerative therapy has gained increased traction as a way to treat musculoskeletal issues. PRP is an autologous source of blood product that contains higher platelet concentration after being prepared in a centrifuge. It is thought that the higher level of growth factors (such as PDGF, TGF-B, VEGF< EGF, bFGF< IGF-1) and cytokines released by the platelets promote a healing cascade. Preclinical and clinical studies have investigated use of PRP on treating various structures including tendons, ligaments and joints. While these trials have shown promising results, there continues to be lack of high-quality studies.
In order to improve the rehabilitation of service members with LBP, novel trials that include PRP must be studied. Although early clinical evidence suggests that PRP therapy may improve outcomes without destruction of tissues, to date, no randomized single blinded placebo-controlled study to look at the effectiveness of PRP injection for lumbar facet mediated joint pain exists.
The study will provide evidence-based medicine on a new regenerative medicine treatment option that may affect significant military personnel with LBP. PRP may offer alternate treatment methods that may help preserve the facet joint structures, improve pain and function without causing destructive lesions or worsening degenerative joints. This healing process may favor improved participation with rehabilitation therapy and ultimately improve return to duty status. This study will also assess the effectiveness of point of care generated PRP, as a minimally invasive treatment option for treating lumbar facet pain. Specifically, PRP effectiveness will be compared to injecting placebo control when injected into facet joints.