Progressive response to botulinum A toxin in cerebral palsy.

Botulinum A toxin (BT) has been successfully used for the management of spasticity in cerebral palsy (CP). However, the long-term results of BT have not yet been determined. We have studied the evolution of a homogeneous group of patients with CP treated with BT. All these patients had an equinus gait resulting from calf muscle spasticity without other muscle group involvement. All of these patients were treated with the same total dose (4 microg/kg) at the same time interval (three months). The mean follow-up time was 33 months. Gait evaluation was made blind on videotape recordings by two independent physicians according to five point scale. All our patients exhibited a progressive improvement in their gait pattern. None of our patients developed fixed contractures nor did any of them need surgical correction. No significant side-effects were seen. The response observed in our study could be due to a progressive symptomatic effect of BT, but it might be also explained by a change in the natural history of the spasticity related to CP, at least in this selected group of patients.