AMSTERDAM, The Netherlands -- For writer's block, the kind that's in the hand rather than the head, consider a shot of botulinum toxin type A, wrote researchers here.
AMSTERDAM, The Netherlands, Dec. 21 -- For writer's block, the kind that's in the hand rather than the head, consider a shot of botulinum toxin type A, wrote researchers here.
In a 12-week study of 40 participants with writer's cramp, those receiving one or two injections of the toxin significantly improved on several clinical rating scales compared with placebo, said Jos J.M. Kruisdijk, M.D., of the University of Amsterdam, and colleagues.
Furthermore, more than twice as many participants in the treatment group versus placebo group chose to continue with the treatment after the 12 weeks, Dr. Kruisdijk and colleagues reported online in Neurology, Neurosurgery, and Psychiatry.
Writer's cramp is a focal hand dystonia brought on by writing with a pen or pencil or other manual tasks. "Although the prevalence is relatively low, varying from three to seven in 100,000, writer's cramp may be responsible for considerable morbidity in terms of working impairment, pain, embarrassment, low self-esteem, and poor social interaction," the authors wrote.
Therapies include physical treatment, postural exercises, relaxation techniques, and special writing devices, "but most of the patients do not obtain satisfactory and sustained benefit," wrote the authors.
The 40 study participants were randomized to a placebo injection or an injection of BoNT-A (botulinum toxin type A), manufactured by Ipsen Pharmaceutical of Wrexham, England. Participants were assessed after one month and given a second injection if there was no response to the first.
Fourteen of 20 patients in the treatment group (70%) reported a beneficial effect and chose to continue treatment after three months, compared with six of 19 patients (31.6%) in the placebo group (P=.03), the researchers reported.
Furthermore, patients in the treatment group showed more improvement on several clinical assessments including a visual analogue handwriting scale (P=.02), a writer's cramp rating scale (P<.01), a writing speed assessment (P=.04), and an overall symptom severity scale (P=.06), the study found.
The treatment group did not do significantly better on a functional status scale (P=.14). "This can be explained by a deterioration of several item scores owing to BoNT-A-induced weakness, although scores for the writing items improved," the authors said.
Weakness in the hand was the chief adverse event of treatment, affecting 18 of the 20 patients in the treatment group. "Weakness in the hand is an important side effect of BoNT-A injections, but despite this disadvantage most patients preferred to continue treatment," the authors said. Pain at the injection site was the other adverse event. Both weakness and pain were always temporary and recovered completely.
All patients were offered treatment at the conclusion of the trial. At one year of follow-up, 20 of the 39 remaining patients were still under treatment "with positive effect," the authors said. One patient had dropped out of the placebo group.
"Some patients expressed dissatisfaction with treatment, despite substantial improvement in the dystonia," the authors wrote. "The overall outcome did not meet their expectations or needs, and they felt that the inconvenience of repeated injections or the weakness in the hand outweighed the benefits of treatment."
"On the other hand, some patients with minimal or mild objective improvement in their dystonia considered the injections very helpful and wished to continue treatment," the authors added. "Continuation of BoNT-A treatment therefore depends on individual preference, in addition to the degree of achieved improvement in the dystonia."
The study demonstrated that botulinum toxin injections were safe and effective compared with placebo for this difficult-to-treat condition, the authors concluded.
The study was funded in part by Ipsen Pharmaceutical, maker of BoNT-A.
In the United States, botulinum toxin type A is marketed under the brand name Botox.