21 patients diagnosed with chronic recalcitrant plantar fasciitis were randomized to receive either dextrose prolotherapy (DP) or autologous platelet-rich plasma (PRP) injection therapy. The purpose was to evaluate the efficacies of these treatments and additionally, to assess whether one is more effective. Results at 28 weeks indicated that both treatments significantly improved total Foot Function Index scores versus baseline but no between-group differences were found. Nevertheless, PRP provided greater overall improvements from baseline in short-term functional subscales and outcome compared to DP.