Construction and validation of a prognostic model for selective posterior rhizotomy in children with spastic cerebral palsy
Maimaiti Abulimiti
Songhai Bedelehan
Yeermike Bieshanbieke
Adilai Tulajiang
YAN Baofeng
Abstract：Objective To develop and validate a prognostic model for children with spastic cerebral palsy who un-dergo selective posterior rhizotomy(SPR).Methods A total of 145 children with spastic cerebral palsy who underwent SPR were retrospectively enrolled.These patients were divided into the training set(n=102)and validation set(n=43)at a ratio of 7:3.The Ashworth scale was employed to assess the lower-limb muscle tone of patients before and after surgery.A decrease of≥1 level in lower-limb muscle tone after surgery was regarded as a favorable prognosis,whereas a decrease of<1 level was considered an unfavorable prognosis.Relevant data of chilren were collected.Univariate and multivariate Logistic regression analyses were used in the training set to screen independent risk factors,and we constructed a nomo-gram prediction model.In the validation set,the model was internally validated using the Bootstrap method with 1,000 resamplings.Its discrimination,goodness-of-fit,calibration,and clinical utility were assessed using the receiver operating characteristic(ROC)curve,Hosmer-Lemeshow test,calibration curve,and decision curve analysis.Results Among the 102 patients in the training set,54 had a favorable prognosis and 48 had an unfavorable prognosis.Among the 43 cere-bral palsy patients in the validation set,28 had a favorable prognosis and 15 had an unfavorable prognosis.Older age(OR=1.269,95%CI:1.098-1.466,P<0.05),Gross Motor Function Classification System(GMFCS)grade Ⅳ-Ⅴ(OR=3.984,95%CI:1.423-11.152,P<0.05),and the inability to sit independently(OR=3.970,95%CI:1.275-12.359,P<0.05)were identified as independent risk factors for the unfavorable prognosis in patients with spastic cerebral palsy.Based on the analysis of influencing factors,the regression equation of the model was obtained as logit(P)=-3.336+0.238×age+1.382×GMFCS grading+1.379×sitting independently.The AUC of the training-set prediction model was 0.801(95%CI:0.712-0.889),and the AUC of the validation-set prediction model was 0.785(95%CI:0.646-0.923).There was no statistically significant difference between the actual probability of an unfavorable prognosis and the predicted probability(χ2=9.182,df=8,P=0.327),indicating a good goodness-of-fit.The calibration plot also demon-strated a high degree of consistency between the predicted model and clinical observations.The model predicted that the probability of an unfavorable prognosis(i.e.,threshold probability)in patients with spastic cerebral palsy ranged from 19%to 96%,both of which were higher than the two extreme lines.Conclusions Older age,GMFCS grade Ⅳ-Ⅴ,and the inability to sit independently are independent risk factors for the unfavorable prognosis in SPR.The risk prediction model constructed based on these risk factors exhibits good discrimination,calibration,and clinical practical value.
Keywords：cerebral palsyselective posterior rhizotomyprognosispredictive model
Publication Date：2026-02-25
Online Publishing Date：2026-03-19(First online date of this platform, not the publication date of the document)
Pages：5( 48-52 )