Objectives: Botulinum toxin A (BoNT-A) is used as an alternative treatment for chronic orthopedic conditions. This study was conducted to investigate the efficacy and safety of BoNT-A on pain and functional outcome in patients with chronic plantar fasciitis.
Methods: In this short-term, randomized, multicenter, double-blind, placebo-controlled study, patients (N=40) were randomized to receive 200 units of BoNT-A (Dysport) or saline placebo. The injection was administered in a fan-shaped manner directly at the calcaneal origin of the plantar fascia. The primary outcome measure was the proportion of responders at week 6 [≥50% decrease from baseline in pain score (visual analog scale) while moving during the previous 48 h). Global assessments were performed by the patient and physician at each visit up to week 18.
Results: More patients in the BoNT-A group achieved a response at week 6 (25% vs. 5% for placebo; P=0.18). Differences between treatments were in favor of BoNT-A on secondary measures of pain, but did not reach statistical significance. In the BoNT-A group, 52.7% (vs. 40% for placebo) assessed their condition as slightly/significantly improved at week 6. At study endpoint (week 18), 63.1% of the BoNT-A group perceived an improvement versus 55% of the placebo group. There was no difference in global assessment between physician and patient. No adverse events related to treatment were noted.
Discussion: There is a need for larger, prospective, long-term, placebo-controlled studies to fully establish the role of BoNT-A for the treatment of plantar fasciitis.