PRP was prepared from 150 or 300 ml of peripheral blood (150ml in unilateral cases and 300ml in bilateral cases). The sample was centrifuged at 1480 rpm for 6 minutes and again at 3400 rpm for 15 minutes to yield 4 or 7 aliquots of PRP, each 5 ml.
One in four PRP samples (PRP group: n = 13; PRP+HA group: n = 8) were analyzed with human enzyme-linked immunosorbent assay kits (Boster Immunoleader) for the following proinflammatory and anti-inflammatory markers:
- Interleukin-6 (IL-6)
- Tumor necrosis factor–a (TNFa)
- Interleukin-1 receptor antagonist (IL-1RA)
- Interleukin-10 (IL-10)
- Tissue inhibitor of metalloproteinases–1 (TIMP1)
- Transforming growth factor–b1 (TGF-b1)
- Vascular endothelial growth factor (VEGF)
Outcomes were assessed with the visual analogue scale (VAS), the Harris Hip Score (HHS), and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Patients were assessed at baseline and again 2 months, 6 months and 12 months after the last injection.
The study found WOMAC scores in the PRP group significantly improved at 2 & 6 month follow-up. Researchers also noted a ‘‘moderate’’ correlation between interleukin-10 and variations of the VAS score. Overall PRP injections alone were found to be more effective than HA injections.