Clinical Bottom Line
“How should I apply this information?”
This study used a unique way of analyzing stride rate data collected for children with cerebral palsy (CP) Gross Motor Function Classification System (GMFCS) levels I–III, children with distal arthrogryposis (AR), and youth who were typically developing (TD) over a 7-day period. The authors used data collected with the StepWatch Activity Monitor (SW). Trajectory curves were developed to represent the average number of minutes per day spent at each stride rate, from inactivity (0 strides/minute) to peak stride rate, for each group. They then compared the amount of inactivity, peak stride rates, and variability in stride rates across the 3 groups of children.
Children with AR and CP had significantly increased periods of inactivity compared with the TD group. This suggests that these youth participate less in age-appropriate physical activities than TD peers. Less variability in walking speed with lower peak stride rates was found in the children with CP compared with the TD group. This was specifically evident in children classified as GMFCS levels II and III who may require orthoses and assistive devices for mobility. Variability is an important component of motor development, and variable walking speed is necessary for full participation in daily activities. Treatment interventions should, therefore, address increasing variability in gait speed for children with CP and AR. As these children age, orthotics and assistive devices should be reevaluated to ensure that they allow for maximum activity level and versatile speed of movement. Finally, SW measures the child's actual performance of the functional activity of walking in their natural environment over the course of the day. This is different from other outcome measures and may be useful if the goal of intervention is to increase a child's ability to keep up with peers in a school setting, or when preparing a child for participation in a recreation/sports program.
“What should I be mindful about in applying this information?”
The reader needs to remember that subjects were from a convenience sample and most were Caucasian. Although the authors analyzed stride rate patterns in a large number of youth who were TD, comparisons were made to smaller groups of children with CP and AR. Data were collected on children between the ages of 6 and 15 years; however, comparisons between the TD and CP groups were for children between 10 and 13 years. The reader also needs to be mindful about the use of secondary analysis of different data sets that may pose a problem of consistency in data collection. There are also many confounding variables; that is, environmental factors, body size, physical condition/fitness, etc, that were not monitored or explained that may affect the child's activity level.
Strengths of the study include (1) nearly equal boys and girls in each age group, (2) clear method of determining noncompliance, (3) data averaged for 5 days within a 7-day period including 1 week-end day, (4) accuracy of the device demonstrated by comparing it to a manual count, and (5) a transformation method used to normalize data. Overall, an adequate picture of children's walking stride rate patterns is demonstrated for wide age range of both boys and girls.
Donna Redman-Bentley, PT, PhD
Western University of Health Sciences,
Mary Wardell, PT, DPT, MS, PCS
Long Beach Memorial Miller Children's Hospital,
Long Beach, California