Segmental Contributions to Trunk Control in Children With Moderate-to-Severe Cerebral Palsy.

Objective: To examine postural constraints in children with moderate-to-severe cerebral palsy (CP) using a segmental approach.

Design: Quasi-experimental repeated-measures study; case series.

Setting: Motor control research laboratory.

Participants: Children (N=15; age range, 4-16y) with moderate (Gross Motor Function Classification System [GMFCS] IV; n=8; 4 boys) or severe (GMFCS V) (n=7; 4 boys) CP.

Interventions: Each child participated in 3 data collection sessions. During each session, we evaluated postural control for sitting using kinematics and clinical assessments.

Main Outcome Measures: Kinematic data were used to document head alignment and stabilization with external support at 4 levels (axillae, midrib, waist, hip). Two clinical assessments, the Segmental Assessment of Trunk Control and behavioral assessment for stage of trunk control, were also used to compare results for children with CP to previous longitudinal data from typically developing (TD) infants (3-9mo of age).

Results: Children with GMFCS V had difficulty aligning and stabilizing their head along the medial-lateral and anterior-posterior axes. External support improved postural control for children with GMFCS V but not for those classified as GMFCS IV, who had opposite responses to support compared with TD infants.

Conclusions: Children with GMFCS V have limited trunk control but respond to support similarly to young TD infants, suggesting delayed postural control. Response to external support for children with GMFCS IV suggests a unique strategy for trunk control not observed in typical infants. Overall a segmental approach offers new insights into development of trunk control in children with moderate-to-severe CP.