ORLANDO — Botulinum toxin injected at the plantar fascia insertion and at the gastrocnemius-soleus complex relieved chronic plantar fasciitis pain better than did standard treatment, according to the findings of a small, randomized controlled trial.
Dr. Mehul J. Desai of George Washington University Hospital in Washington and associates randomly assigned 10 patients with chronic unilateral plantar fasciitis and a mean age of 35 years into two groups. The five patients in the experimental treatment group received 50 U of botulinum toxin type A at the plantar fascia insertion, 50 U at the motor point of the soleus muscle, and 25 U at both the medial and lateral gastrocnemius motor points. Patients in the standard treatment group received 50 U of botulinum toxin type A at the plantar fascia insertion and saline at the 3 other sites.
The patients were assessed before the injections, and at 4, 8, and 12 weeks following treatment.
At study completion, patients in the experimental treatment group went from 7.9 points on a 10-point visual analog scale to 1.9 points. By comparison, patients who received the standard treatment went from 4.4 points to 2.4 points. The difference between the two groups was significant, Dr. Desai reported at the annual meeting of the American Academy of Pain Medicine.
Gait also was substantially improved from baseline in the experimental treatment group, as shown by significant improvement in ankle and hip ranges of motion.
Limited ankle dorsiflexion, secondary to a tight gastrocnemius-soleus complex, is the most important risk factor for the development of plantar fasciitis, according to Dr. Desai. “Our hope is that instead of just treating the symptom, which is at the plantar fascia, we are also treating the tight medial and lateral gastrocnemius and soleus muscles and thereby correcting the underlying biomechanical problem.”
Dr. Desai disclosed no conflicts of interest. Funding for the study was provided by Allergan Inc., a producer of botulinum toxin type A.
Botulinum toxin type A is injected locally, at the plantar fascia insertion site (shown), and distally. Courtesy Dr. Mehul J. Desai