Analysis of long-term effect of selective posterior rhizotomy for treatment of spasticity of lower limbs in cerebral palsy patients

Abstract

Objective Selective posterior rhizotomy (SPR) of lumbosacral region was a well-recognized treatment for spasticity of lower limbs in spastic cerebral palsy (CP).However,there was still no agreement on long-term outcome of SPR.The purpose of this study was to assess the long-term outcome in a large amount of patients by using quantitative,standardized assessment tools.Methods 141 patients who had undergone SPR from Jan.2001 to Dec.2006 were followed-up with integrated clinical data for at least 9 years averagely.The outcomes were assessed at the time points of 1 year,5 years and final trace after operation respectively with quantitative,standardized assessment tools,including Modified Ashworth Scale (MAS),Gross Motor Function Classification System (GMFCS) and performance of Activities of Daily Living Scale(ADL).Combined with the subsequent treatment which was required by those patients,statistical analysis was performed to evaluate the long term effects of SPR.Results MAS scores in hip adductors,knee flexors and ankle plantar flexors were reduced persistently until the final follow-up visit and the differences were statistically significant (P ＜ 0.01).The overall improvement rate of muscle tone during follow-up was 90.7％.The distribution of GMFCS was statistically different compared with preoperative levels(P ＜ 0.01).The overall improvement rate of gross motor function compared with preoperative was 80.1％.ADL scores were statistically different when compared with preoperative group(P ＜0.01).The overall improvement rate of quality of life was 88.9％.When stratified by the preoperative GMFCS,the ADL Scores of GMFCS Group Ⅱ and Ⅲ continued to increase after SPR.The proportion of patients who received subsequent procedures including selective peripheral neurotomy (SPN),Achilles tendon lengthening,orthopedic surgery and botulinum toxin treatment was 27.7％ at final follow-up.The independent-samples T test showed that the necessary subsequent surgical treatments after operation significantly increased the last follow-up ADL score improvement(P ＜ 0.01).Conclusions The benefits of SPR were persistent in the majority of patients.These benefits were mainly improved muscle tone,gross motor function,and performance of ADL.Patients in preoperative GMFCS Groups Ⅱ and Ⅲ were most likely to display these long-term benefits.Postoperative necessary subsequent surgical treatments contributed to maintaining and improving motor function,and eventually improved the performance of activities of daily living. Key words: Rhizotomy; Cerebral palsy; Muscle spasticity; Lower extremity ; Long-term effect