Objective
To determine the effective and safe dose of Dysport^Ⱂ (one of the commercial botulinum toxins) for relieving the spasticity of calf muscle in cerebral palsy.

Method
Twenty spastic cerebral palsy children (34 limbs) were randomly assigned to a high dose (HD; 16 Unit/ kg/limb) injection group and low dose (LD; 8 Unit/kg/limb) injection group. Locomotor rating scale (LRS) and parameters of 3 dimensional gait analysis including ankle dorsiflexion angle at stance phase (MADA), maximal dynamic gastrocnemius (MDGL) and soleus length (MDSL) were assessed before, 4 weeks after, and 12 weeks after injection.

Results
Mean LRS, MADAs, MDGLs and MDSLs were significantly increased both 4 and 12 weeks after injection in HD group. In LD group, LRS, MADAs, MDGLs and MDSLs showed some improvement but they were statistically insignificant. The high dose had no adverse effect except the mild and transient weakness, which was tolerable to the cerebral palsy patients.

Conclusion
The present study demonstrated the high dose injection of Dysport^Ⱂ was more effective than the low dose injection to relieve the spasticity of calf muscle in cerebral palsy. (J Korean Acad Rehab Med 2002; 26: 279-284)