Is Standing Function Improved After Orthopaedic Surgery in Children With Cerebral Palsy at GMFCS Levels III/IV?

Abstract

Children with cerebral palsy (CP) at Gross Motor Function Classification System (GMFCS) levels III/IV are at risk for losses in standing function during adolescence and transition to adulthood. Multilevel surgery (MLS) is an effective treatment to improve gait, but its effects on standing function are not well documented. The objectives of our study were to describe standing function in children with CP classified as GMFCS levels III/IV and evaluate change after MLS. This retrospective study included children with CP (GMFCS III/IV) ages 6 to 20 years who underwent instrumented gait analysis. A subset who underwent MLS were evaluated for change. Primary outcome measures were Gross Motor Function Measure dimension D, gait velocity, functional mobility scale, and the Pediatric Outcomes Data Collection Instrument (PODCI). Additional impairment level measures included foot pressure, knee extension during stance phase of gait, and knee extension passive range of motion. Four hundred thirty-seven instrumented gait analysis sessions from 321 children with CP (ages 13.7±4.8y; GMFCS III-81%/IV-19%) were included. The GMFCS III group had higher Gross Motor Function Measure dimension D, gait velocity, PODCI scores, and better knee extension compared with the GMFCS IV group ( P <0.05); 94 MLS were evaluated for postoperative change 15.3±4.2 months after MLS. Children at GMFCS level III had improved PODCI scores ( P <0.05), better knee extension passive range of motion ( P <0.01), and improved coronal plane foot pressure ( P <0.05) post MLS. Maximum knee extension during stance and heel impulse improved significantly in both groups ( P <0.01). Standing function of children with CP at GMFCS IV was significantly more limited than at GMFCS III. After MLS, both groups (III/IV) showed improvement in impairment level outcomes (knee extension and foot position), whereas only those functioning at GMFCS III had improvement in activity/participation outcomes according to the PODCI. For children with CP at GMFCS levels IV, MLS may improve standing function, but appropriate goals related to assisted standing and measurement protocols sensitive to limited functional mobility should be adopted. Level III-retrospective comparative study.