A Randomized Placebo-Controlled Trial of Platelet Rich Plasma (PRP) for Facet Mediated Lumbar Low Back Pain

This randomized controlled trial will determine the efficacy of platelet rich plasma vs. Control/Placebo. 170 healthy, physically active individuals with facet mediated lumbar low back pain will be recruited to participate in the study. Part of the formal screening procedures, consented participants will undergo a fluoroscopic guided diagnostic lumbar medial branch block (MBB) within 60 days after consent. The results of the diagnostic MBB will determine if they meet final eligibility criteria (facetogenic pathology) and should continue on with the therapeutic injection. In the rare case that there is a positive MBB within the past three months, then it will not be repeated. To clarify, the diagnostic MBB will determine if the procedure will be beneficial to the participant by confirming they have facet-mediated low back pain and that the experimental procedure may benefit them. This avoids participants continuing in the study who would not benefit from the PRP injection.

Participants will be asked to complete a standard pain diary following the lumbar MBB procedure. Participants who experience a positive test result from the MBB (as indicated by a reduction of ≥50% in pain symptoms using the 8 hour pain diary) will be eligible to proceed with the study. Following the stated inclusion/exclusion criteria, participants who do not experience a positive test result (indicate a reduction < 50% in pain symptoms) will be formally withdrawn from the study at this point and will resume normal care with their referring physician to explore their best treatment option(s).

Any female participant of child-bearing age will also be required to have a urine hCG test performed prior to the diagnostic or therapeutic injection being performed. If the urine hCG indicates the participant is pregnant, per stated inclusion/exclusion criteria, they will be formally withdrawn from the study at this point and will resume normal care with their referring provider.

Participants who meet final eligibility criteria (positive lumbar MBB and, if applicable, negative pregnancy test) will be randomized to a study arm within one week of the MBB. A computer-generated randomization program prepared by the study biostatistician will be used to assign participants 1:1 across both study arms (PRP vs. Control/Placebo).

The target area for either the PRP or saline injection will be the intra-articular facet joint. During this time, adequate amount of peripheral blood will be drawn by a clinic nurse; either 30ml if injecting single side, or 60ml will be drawn if injecting both sides. PRP mixture will be prepared using a point of care centrifuge system. Participants in the PRP group will receive 1 ml of PRP mixture for each facet joint. Participants in the control/placebo group will receive 1 ml of normal saline for each facet joint.