The Efficacy of Botulinum Toxin vs. Corticosteroid for the Treatment of Refractory Plantar Fasciitis

The Efficacy of Botulinum Toxin to the Flexor Digitorum Brevis Versus Corticosteroid to the Plantar Fascia for the Treatment of Refractory Plantar Fasciitis: A Randomized-Controlled Trial

This single-blinded, randomized-controlled trial compares the efficacy of ultrasound-guided onabotulinumtoxinA (BTX-A) injections to the flexor digitorum brevis with current standard of care corticosteroid injections to the plantar fascia for the treatment of refractory plantar fasciitis in patients that have failed six weeks of non-operative treatment.

Treatment of plantar fasciitis is not well described in the current literature, often making management difficult for both providers and patients. Recent literature has suggested potential use of Onabotulinumtoxin A (BTX-A) as an effective treatment to reduce pain and allow patients to return to their previous level of functional activity. The study will consist of veteran patients at the George E Wahlen Department of Veteran's Affairs (SLC VA) in Salt Lake City, UT. This pilot study aims to randomize patients with plantar fasciitis into current standard of care treatment with corticosteroid injection into the plantar fascia and experimental treatment with BTX-A injection into the flexor digitorum brevis cohorts. We predict that those who receive BTX-A injections will report better outcomes on the Numeric Pain Rating Scale (NPRS) as well as the Foot and Ankle Ability Measure (FAAM) when compared to those receiving corticosteroid. The results of this study could aid in providing evidence towards more reliable and beneficial treatment of plantar fasciitis.

1 mL of 4 mg/mL dexamethasone with 2 mL of 1% lidocaine OR 1 mL of 4 mg/mL dexamethasone, 1 mL of 2% lidocaine and 1 mL saline

20 units of Onabotulinum A in 200 µL of saline injected into the flexor digitorum brevis via ultrasound-guidance

1 mL of 4 mg/mL dexamethasone with 2 mL of 1% lidocaine OR 1 mL of 4 mg/mL dexamethasone, 1 mL of 2% lidocaine and 1 mL saline injected into the plantar fascia

Inclusion Criteria: Diagnosed increased pain when pressure applied at the medial calcaneal tubercle X-ray negative for calcaneal fractures or tumors Patient with plantar fasciitis who have failed 6 weeks of non-operative treatment Exclusion Criteria: Prior botulinum toxin injections in the plantar fascia Any botulinum toxin injections in the past 3 months Cortisone injection in the plantar fascia in the previous 3 months Previous surgery on the plantar fascia Active workers compensation claim for plantar fasciitis Active infection or fever Botox or steroid allergy Pregnancy Current other treatment specific to the plantar fascia or intent to undergo during the trial