Patients and methods: This single-center, randomized controlled, double-blind trial was conducted with 38 patients (24 females, 14 males; mean age: 48.2±6.1 years; range, 30 to 57 years) with PF between October 2018 and October 2020. Patients with definitive PF fulfilled the eligibility requirements and were included in the study. Block randomization was used to assign each patient to CSI and DP treatment arms. Patients in the CSI and DP treatment arms received methylprednisolone and dextrose, respectively. Lidocaine injection was used for local anesthesia, and ultrasound was used to guide these minimally invasive procedures. Patients were followed up after one (short term) and three months (middle term). Primary outcomes were pain severity and foot function.

Results: In both groups, we detected a significant improvement in pain severity and foot function index in the middle term, which was slightly more profound in the DP group. In contrast to the CSI arm, DP did not appear to alleviate pain in the short term. We observed a waning treatment effectiveness in the CSI arm over time.

Conclusion: Both CSI and DP were effective in treating PF by reducing pain and improving foot function index in the middle term. While CSI ensures better short-term outcomes, its effectiveness tends to wane over time. On the contrary, DP does not provide significant short-term relief but is more effective in the middle term. Further trials are needed to support these findings. Keywords : Corticosteroid injection, foot function index, plantar fasciitis, prolotherapy