Botulinum toxin type A injection increases range of motion in hip, knee and ankle joint contractures of children with cerebral palsy.

Objectives: This study aims to evaluate the clinical outcomes of children with spastic type cerebral palsy (CP) treated with botulinum toxin type A (BoNT-A) injection for lower limb contracture and the influence of age, gender, functional level and degree of initial contracture on treatment outcomes.

Patients and methods: Clinical records at pre-BoNT-A injection and post-BoNT-A injections of 153 sessions of a total of 118 consecutive children (67 boys, 51 girls; mean age 5.9±2.6 years; range, 2.5-16 years) were retrospectively evaluated. Degrees of pre- and post-injection contracture were evaluated. Post-injection supplemental casting for 10 days was recorded in all cases. Less than 20° of hip flexion contracture, more than 30° of hip abduction, a negative prone Ely test, less than 50° of popliteal angle and at least 5° of ankle dorsiflexion values at post-injection were accepted as sufficient clinical improvement.

Results: Sufficient post-injection range of motion (ROM) was observed in 80% of cases with hip flexion contracture, in 45% of cases with hip adduction contracture, in 84% of cases with knee flexion contracture and in 77% of cases with ankle equinus contracture. Prone Ely test that was positive in 60% of cases with knee extension contracture was negative at post-injection. Improvement in contractures were prominent in children with lesser degree initial contractures.

Conclusion: Botulinum toxin type A injection increases ROM in hip, knee and ankle joint contractures in CP. Although age, gender and functional level may influence the clinical outcomes, pre-treatment level of contracture is the main determinant in improvement in ROM at post-injection.