[Writer's cramp treated with botulinum injections]

OBJECTIVE

To evaluate the first clinical experience with local botulinum toxin A (BTA) injections in patients with writer's cramp.

DESIGN

Descriptive.

SETTING

Academic Medical Centre, Amsterdam, the Netherlands.

METHOD

In May 1993-January 1996 ten patients with writer's cramp were treated with BTA (Dysport). Age of the patients varied from 28 to 68 years, the duration of complaints from 1 to 29 years. Muscles for injections were selected by observation, sometimes combined with electromyography. BTA was administered under electromyographic guidance.

RESULTS

The amount of BTA administered per treatment session ranged from 15 to 400 IU. In three patients the BTA-induced weakness necessary to reach a beneficial effect on writing was unacceptable. In seven patients the response was satisfactory or good and lasted 2 to 15 months (mean: 3.5 months).

CONCLUSION

The results confirm the efficacy of BTA in writer's cramp.

Measurement of patellar and ankle tendon reflexes in normal subjects

In order to acquire normal values, patellar and ankle tendon reflexes were measured bilateral in 51 healthy subjects. The reflexes were mechanically evoked with a hand-held hammer which was connected to the trigger input of a two-channel EMG system. For each reflex simultaneous registration took place from surface electrodes on two different locations. The dependence of the latency on body length and age is described as well as the left-right difference and the intra-individual variability. Using similar measurement conditions significantly longer latencies were found than those published earlier. The importance of well defined placement of the electrodes when comparing acquired latencies with normal values is shown.

[The treatment of hemifacial spasms using botulin]

At the Academic Medical Center of the University of Amsterdam the results of treatment of hemifacial spasms (HFS) with botulinum toxin type A were evaluated in a pilot study. Five men and 21 women with HFS were treated with toxin injections. The mean age was 65 years. Most patients were referred from other centers and had been previously treated without success with various medications or with surgical treatment. Treatment took place at the outpatient department. The toxin was injected into the M. orbicularis oculi at the medial and lateral sides of the upper and lower lids. The total dose varied between 6 and 16 LD50. Patients were reinjected on demand. All patients except for one reported satisfying improvement of their spasm. The onset of the beneficial effect was 1-2 days after the injection and the effect lasted about 3 months. All patients were re-examined 1 to 2 weeks after each treatment and showed reduction or disappearance of synkinesias. No systemic side effects occurred and local complications were mild and transient. We conclude that local injection of botulinum toxin appears to be a successful alternative in the current treatment of hemifacial spasm.