Botulinum toxin injection decreases plantar fasciitis pain

[Guest guest]



Botulinum toxin injection decreases plantar fasciitis pain



Nov 1, 2005



Elaine Zablocki



Berlin, Germany - A single injection of botulinum A toxin appears to

decrease chronic plantar fasciitis pain, with the improvement lasting

at least a year [1]. The findings come from a pilot study in nine

patients reported in the November 2005 issue of the ls of the

Rheumatic Diseases, and the authors are now planning a larger,

placebo-controlled trial.

The toxin is already used medically to ease severe muscular

contractions in cerebral-palsy patients and is notoriously used as a

beauty aid to iron out wrinkles and skin creases. It has also been

explored for use in tension headaches and back pain, but this is the

first reported use in plantar fasciitis.

" This hypothesis occurred to us because the literature suggests that

botulinum toxin may have a pain-reducing effect and decrease

inflammatory reactions, " lead author Dr Placzek (Charite

University Medicine, Berlin, Germany) tells rheumawire. " In an

article in Pain last year, Cui reported a reduction of inflammation

due to botulinum toxin after formalin-induced inflammation in his rat

model. [2] "

Placzek and colleagues investigated the effects of a single injection

of toxin A in an open case series. Study participants were at least

18 years of age and had experienced pain that scored at least four

points (on a 0-10 scale) during the past 48 hours. They'd had chronic

plantar fasciitis for at least four months (except for one patient,

whose disease duration disease was only two months), and the average

disease period was 14 months (range 2-36). They'd all tried at least

two unsuccessful conservative treatments.

Potential participants were excluded if they had received prior

treatment with botulinum toxin or had presence of a rheumatoid

disease, known muscle diseases, were pregnant or lactating, or had

serious systemic diseases or abuse of alcohol or drugs.

Nine patients were treated with 200 units of botulinum toxin A

(Dysport, Ipsen-Pharma, UK) injected subfascially in four directions

through one puncture at the origin of the plantar fascia.

Pain levels were measured at intervals starting two weeks after the

injection and ending 52 weeks afterward. Several methods were used

for pain measurement, including visual analog scales (1-10) for pain

at rest during the past 48 hours and for the greatest pain during the

same time period. The Mainz Pain Staging System was used to evaluate

pain at the time of the injection and at the final visit a year later.

Decrease in pain lasts for a year

Two weeks after the injection, researchers observed " a pronounced and

statistically significant reduction of pain at rest during the past

48 hours using a visual analog scale (p<0.012). Maximum pain during

the past 48 hours was similarly reduced (p<0.015). " A year after the

injection, pain continued to be significantly reduced.

The muscle force of the foot and the great toe were measured at

intervals using Brunner's method (scale 0-5). " Undesirable effects

such as muscle weakness or systemic reactions were not seen, " the

authors write. " Our patients were satisfied not only by the pain

relief but also that only one injection was needed. The treatment is

cost effective compared with repeated physical treatment,

acupuncture, or extracorporeal shock-wave therapy. "

Preliminary results, larger study under way

" This is a very preliminary article, and it doesn't really evaluate

the treatment compared with established treatment. The authors

themselves emphasize the preliminary nature of this study, " says Dr

W Brodsky, president of the American Orthopaedic Foot and Ankle

Society, an association of orthopedic surgeons specializing in foot

and ankle problems. " There's always the potential for the placebo

effect. "

In fact, the authors currently have a double-blind, placebo-

controlled multicenter study under way (n=50, five to six centers).

They expect to complete it within about a year.

Plantar fasciitis annoying but self-limiting

Plantar fasciitis is very common, Brodsky says. " It may even be an

affliction of modern life, related to the hard surfaces we've created

in our cities, homes, and workplaces. This condition is persistent

and annoying, it can interfere with the activities of everyday life

and work, but it is not permanently damaging. Most often it is a self-

limited condition. It frequently takes a year or more, but the vast,

vast majority of these cases do resolve. "

Most cases of plantar fasciitis are appropriately and successfully

treated with simple, conservative, nonoperative therapies, Brodsky

tells rheumawire. These methods include Achilles-tendon- and plantar-

fascia-stretching exercises, activity modification, and use of

cushioning shoes, heel lifts, heel wedges, and insoles.

If further research confirms that botulinum toxin does ease the pain

of plantar fasciitis, it could be a useful treatment for the small

subset of cases that do not respond to conservative treatment,

Brodsky says. It is " a very expensive drug, and cost effectiveness is

an issue. We should always look for new therapies that would benefit

our patients. But at the same time, we have to exercise an

appropriate, healthy measure of skeptical reserve. If we eventually

decide to use botulinum toxin injections for this condition, we have

to be sure they're used appropriately, for only a select percentage

of refractory patients. "

Placzek R, Deuretzbacher G, Buttgereit F, Meiss AL. Treatment of

chronic plantar fasciitis with botulinum toxin A: an open case series

with a 1 year follow up. Ann Rheum Dis 2005; 64:1659-61. 16227422 Cui

M, Khanijou S, Rubino J, Aoki KR. Subcutaneous administration of

botulinum toxin A reduces formalin-induced pain. Pain 2004;

107:125-33. 14715398

PMID: 14715398