Therapeutic Effect of Extracorporeal Shock Wave Therapy According to Treatment Session on Gastrocnemius Muscle Spasticity in Children With Spastic Cerebral Palsy: A Pilot Study

OBJECTIVE: To investigate the therapeutic effect of extracorporeal shockwave therapy (ESWT) according to treatment session on gastrocnemius muscle spasticity in children with spastic cerebral palsy (CP). METHODS: Twelve children with spastic CP underwent 1 ESWT and 2 sham ESWT sessions for gastrocnemius (group 1) or 3 ESWT sessions (group 2) once per week for 3 weeks. Modified Ashworth Scale (MAS) score, passive range of motion (PROM) of the ankle plantar-flexor muscles with knee extension, and median red pixel intensity (RPI) of color histogram of medial gastrocnemius on real-time sonoelastography (RTS) were measured before ESWT, immediately after the first and third ESWT, and at 4 weeks after the third ESWT. RESULTS: Mean ankle PROM was significantly increased whereas as mean ankle MAS and median gastrocnemius RPI were significantly decreased in both groups after the first ESWT. Clinical and RTS parameters before ESWT were not significantly different from those immediately after the third ESWT or at 4 weeks after the third ESWT in group 1. However, they were significantly different from those immediately after the third ESWT or at 4 weeks after the third ESWT in group 2. Mean ankle PROM, mean ankle MAS, and median gastrocnemius RPI in group 2 were significantly different from that in group 1 at 4 weeks or immediately after the third ESWT. CONCLUSION: The therapeutic effect of ESWT on spastic medial gastrocnemius in children with spastic CP is dependent on the number of ESWT sessions.