This prospective open-label multicenter trial enrolled 207 children with CP and dynamic equinus foot deformity. It evaluated the long-term safety and efficacy of repeated BTX-A injections (4 U/kg, up to 200 U, every 3 months) over a mean follow-up of 1.46 years per patient. The primary outcome was the Physician Rating Scale of dynamic gait pattern.
When a child with CP presents with toe-walking from gastrocnemius-soleus spasticity and no fixed contracture on exam, BTX-A injection is a first-line option — this trial established that repeated injections maintain gait improvement for at least 2 years with an excellent safety record.
The key decision point is contracture versus dynamic spasticity. BTX-A targets the dynamic component. Once a fixed contracture develops, the window for chemodenervation closes and surgical lengthening becomes necessary.
Serial injections every 3 months are the practical dosing framework: the drug effect lasts 3–5 months, and re-injecting before full recovery of tone keeps the child in a window where physical therapy can capitalize on reduced spasticity to reinforce better movement patterns and lengthen the muscle-tendon unit.
Antibody formation should not reflexively stop treatment — 73% of antibody-positive patients still responded. Reserve concern for the patient who is both antibody-positive and losing clinical response, which occurred in only 6% of this cohort.
This prospective open-label multicenter trial enrolled 207 children with CP and dynamic equinus foot deformity. It evaluated the long-term safety and efficacy of repeated BTX-A injections (4 U/kg, up to 200 U, every 3 months) over a mean follow-up of 1.46 years per patient. The primary outcome was the Physician Rating Scale of dynamic gait pattern.
When a child with CP presents with toe-walking from gastrocnemius-soleus spasticity and no fixed contracture on exam, BTX-A injection is a first-line option — this trial established that repeated injections maintain gait improvement for at least 2 years with an excellent safety record.
The key decision point is contracture versus dynamic spasticity. BTX-A targets the dynamic component. Once a fixed contracture develops, the window for chemodenervation closes and surgical lengthening becomes necessary.
Serial injections every 3 months are the practical dosing framework: the drug effect lasts 3–5 months, and re-injecting before full recovery of tone keeps the child in a window where physical therapy can capitalize on reduced spasticity to reinforce better movement patterns and lengthen the muscle-tendon unit.
Antibody formation should not reflexively stop treatment — 73% of antibody-positive patients still responded. Reserve concern for the patient who is both antibody-positive and losing clinical response, which occurred in only 6% of this cohort.