Self-initiated Movement During Physical Therapy in Young Children with Cerebral Palsy

Purpose/Hypothesis: Gross motor practice in infants with typical development is overwhelmingly self-initiated. Young children with cerebral palsy (CP) have more difficulty moving independently, but the frequency of their initiation of movement has not been studied. Physical therapists often balance competing priorities of facilitating practice of challenging motor activities with facilitating child-directed motor play and exploration. Our objectives were to quantify self-initiated movement in young children with CP during physical therapy (PT), and to determine if there was a relationship between movement initiation and gross motor function.

Number of Subjects: Thirty-seven toddlers with CP (20 boys, mean age 26.3 months, GMFCS I-IV) were included. Children were enrolled in a clinical trial (NCT#02340026) and could not take independent steps.

Materials/Methods: Participants were randomly allocated to conventional PT (dose-matched control group) or to an intervention that encouraged (among other things) child-directed movement by using dynamic body weight support (experimental group). Participants were stratified by age and gross motor function to ensure equivalence at baseline. Videos of randomly selected biweekly therapy sessions (271 total) were coded for two types of movement initiation – initiation of a new movement/posture and selection of the motor pattern. Videos had been previously coded for movement/posture (i.e. sit, crawl, transition, etc). For each of the pre-coded gross motor activities, the initiation coder selected ‘therapist’ or ‘child’ for who initiated the motor activity (had the idea) and who selected the motor pattern (assigned to therapist if physical or verbal cues were given). Videos were 20% double coded for reliability, and disagreements were reconciled for any video that didn’t reach 85% reliability. Group differences were assessed with unpaired t-tests and the relationship to motor function (GMFM-66) was quantified by Pearson correlation.

Results: Reliability exceeded 85% for 143 videos (53.7%) for movement initiation and 170 videos (62.7%) for motor pattern selection. Consensus on disagreements was reached for the remaining 128 and 101 videos, respectively. Movement initiation was significantly greater (p=0.004) in the experimental (80.4%, SD 13.2%) compared to the conventional (67.9%, SD 11.7%) group. Similarly, selection of motor pattern was greater (p=0.005) in the experimental (90.6%, SD 9.0%) compared to the conventional (77.6%, SD 15.1%) group, indicating that child-initiation of motor practice can be manipulated in PT. As expected, greater movement initiation was related to higher gross motor function in both groups (experimental group r=0.73, p=0.0005; control group r=0.75, p=0.0003).

Conclusions: Young children with CP initiate motor activity less often than their peers with typical development, with greater motor impairment related to fewer child-initiated activities.

Clinical Relevance: Child-initiation of motor practice can be manipulated in PT for young children with CP, even those with significant motor impairment. Future work should explore the relationship between self-initiation of movement and rehabilitation outcomes.