Table 2.

Platelet-rich plasma (PRP) treatment in knee OA: anti-inflammatory properties.

Reference	Intervention	Patients	Duration	Results
Huang et al. [163]	2–14 mL intraarticular PRP weekly versus Placebo (10 mL saline solution) weekly	PRP (N = 310) Placebo (N = 56)	8 weeks	Significant improvements in plasma IL-1β, IL-6, TNFα, IL-17A, RANKL, and IFNγ were observed in the treatment group.
Xu et al. [164]	4 mL intraarticular PRP, 3 injections per knee, half-month interval 2 mL intraarticular HA, 3 injections per knee, half-month interval 4 mL PRP + 2 mL HA, 3 injections per knee, half-month interval	PRP (N = 40 knees) HA (N = 34 knees) PRP + HA (48 knees) N = 78 patients total (122 knees) N = 44 patients received bilateral injections	24 months	IL-1β, TNFα, TIMP1, and MMP-3 demonstrated significant decreases in the PRP group at 6 months posttreatment. Nevertheless, the PRP + HA group showed better results in this respect. Additionally, the PRP + HA cohort displayed IL-1β, TNFα, TIMP1, and MMP-3 inhibition at 12 months post-injection.