Understanding the development of children with cerebral palsy and how therapy may affect patient-centered outcomes

Background: Knowledge of developmental trajectories of body structure/function and participation in family/recreation and self-care activities in children with cerebral palsy (CP) would help rehabilitation professionals and parents engage in joint decision-making on prognosis, goals, and services.

Objectives: (1) To create developmental trajectories of body structure/function and participation for children with CP and (2) to explore relationships between services and outcomes. We hypothesized the following: (1) The development of children with CP varies based on their functional ability classification, with lower as compared with higher functional ability leading to smaller improvements in their development; (2) younger children with CP would improve at a greater rate than older children; (3) children with CP who developed at the highest level would have received family-centered services with more focus on task-specific practice and environmental modifications, and parents would report their child’s needs were met to a greater extent as compared with those developing at the lower levels.

Methods: We undertook a prospective longitudinal cohort design with 708 children with CP, 1.5 to 11.9 years old, and their parents recruited from 45 sites, clinics, or practices in the United States and Canada. Trained therapists assessed children 2 to 5 times over 2 years using valid, reliable, standardized measures of balance, spinal alignment/range of motion, strength, and endurance. A smaller substudy of children with CP in 2 sites tracked walking and physical activity. Parents completed questionnaires on family demographics and on their children’s endurance, health, participation in family/recreation activities, ability to perform self-care activities, and rehabilitation services. Physical and occupational therapists and parents collaboratively classified children on the Gross Motor Function Classification System (GMFCS). We analyzed body structure/function and participation data using linear and nonlinear mixedeffects modeling to create developmental trajectories for GMFCS levels. We explored relationships between service amount, focus, family-centeredness, and the extent to which children’s needs were met by services and outcomes of balance, endurance, and participation by (1) adding services to the longitudinal curves and evaluating model fits, and (2) using multinomial models to determine relationships to percentile categories of progressing “more than” (>90th percentile) and “less than” (<10th percentile) to the reference of “as expected” (20th to 80th percentile)

Results: Developmental trajectories overall indicate that children with lower functional ability had smaller improvements and improved more during younger ages. Four measures varied from this pattern: (1) impact of health conditions, which basically remained constant; (2) spinal alignment/range of motion limitations, which increased linearly; (3) strength, which increased and decreased linearly dependent on GMFCS level; and (4) the substudy measures of walking and physical activity, most of which showed decreases over time. Exploratory analyses of services to outcomes revealed several positive relationships to participation outcome percentile categories for the extent to which services were meeting children’s needs; familycenteredness; and a focus on structured play/recreation activities, health, and well-being. Amount of services showed relationships to children’s functional ability level, with more services to children with lower functional ability who showed smaller changes on the outcomes.

Conclusions: Developmental trajectories for children with CP by GMFCS levels should help rehabilitation professionals and families discuss prognosis and collaborate on service planning. Services that are family-centered; engage in joint decision-making; consider the needs of the child; and focus on structured play/recreational activities, health, and well-being may enhance interventions for children with CP and their families.

Limitations: Generalization of the developmental trajectories results to children with diagnoses other than CP or for children from countries/cultures other than the United States or Canada should be applied cautiously due to differences in diagnoses’ developmental patterns, parental beliefs, environments, and how health care services are provided. The design of the study was not well suited to the evaluation of services effects, and services were parent-reported estimates; therefore, generalization of the service results by policymakers should be done cautiously.