The emergence of effective, efficient, independent mobility during a child's first years of life is important for the child's biological and behavioral development and shapes the functioning of the family.1–6 The daily life of infants and toddlers with typical development involves hours of mobility nested within exploration, socialization, and object play at home and in the community.7–12 Children with mobility disorders, such as cerebral palsy (CP), have reduced mobility and fewer opportunities to independently explore their world.13 They are, therefore, at risk for secondary impairments in both biological and behavioral development.13 Pediatric rehabilitation, through training and assistive technology, seeks to provide children with special needs with this same level of mobility, exploration, and socialization.14–22
Power mobility (such as power wheelchairs) provides the potential for children with mobility disorders to move more independently and increase their exploration and social interaction.15,16,18 Starting powered mobility as part of a comprehensive early intervention (EI) program within the first years of life may provide mobility and reduce the risks for secondary impairments.23,24 However, very little empirical evidence of the effects or even feasibility of early power mobility training exists.14,19,23,25 This case report is another in a series to document the feasibility of implementing early power mobility programs for a range of pediatric populations using various devices and intervention strategies within various natural environments.23,25–27
Currently, the most critical barrier to including power mobility in EI programs is the lack of readily available power chairs for children younger than 2 to 3 years.28 Even if available, several characteristics of these devices limit the frequency, duration, and/or type of use in natural environments such as homes, classrooms, and playgrounds.23,26,28–30 These limitations include price (eg, devices cost more than $5000 with many costing more than $20 000), size and weight (eg, weighing more than 150 lb), transportation requirements (eg, van or truck), maintenance, aesthetics, and social acceptance.22,29 Furthermore, power chairs have historically been designed to address a limited set of goals related to mobility with minimal consideration of International Classification of Function (ICF) components, specifically body structure and function. That is, children are not expected to gain strength, balance, coordination, or ambulation level through the use of a power chair. Experimental power mobility devices have the potential to address some of these limitations such as size, weight, and early use, but are likely years away from commercial availability.23,25,26 We believe that an urgent and immediate need exists for readily available power mobility options for use by infants and toddlers that address the above limitations while expanding the role of power devices beyond mobility and into the spectrum of ICF components including body structure and function.
The purpose of this case report was to determine the feasibility of using a “ride-on toy car” as a readily available, low-cost, fun, and functional option for families, clinicians, and early childhood educators.31 In our clinical and research work, we have noted several strengths of using these cars. First, the cost is dramatically less than that of power chairs.31 Second, most toy cars are lightweight, small, and easily transported without additional equipment. Third, the child-friendly, colorful, playful designs are viewed by adults and children as a toy rather than as a medical device. This may be an especially important aspect for clinicians wanting to start power mobility training with families hesitant to discuss power chair options. Fourth, because these cars are simple plastic electromechanical devices, they can be modified quickly and easily to match a range of current and/or future abilities and goals. Finally, they appear robust enough for a few hours of use per day for a year or more.
We have recently published a technical report on the basic components and exemplar modifications based on the use of these cars for clinical research.31 No studies have been published on the effectiveness or even the feasibility of including these cars in clinical practice with any pediatric population. Thus, basic questions as to the child's sitting tolerance, driving ability, and interest in daily use as well as family compliance have not been formally addressed. Answering these questions is important both for more wide spread clinical and community use and for designing the initial group studies. This case report focuses on 3 specific questions. Could we (1) select and modify a car such that a child with severe postural and movement impairments consistently enjoyed sitting and driving, (2) conduct a family-centered driver training program that resulted in a high level of fun and compliance by the child and family; and (3) select a set of variables that quantify the changes in independent mobility, socialization, and self-care that our team noted qualitatively?
DESCRIPTION OF THE CASE
This report involved a 21-month-old child, Brenden, with a diagnosis of spastic quadriplegic CP. This report began after the family and therapists expressed a need for options to increase his independent mobility and social interactions in his classroom at a university-based Early Learning Center (ELC) and at home. Informed consent for the child to participate, for his name and picture to be used, and for the family to assume the risks of car use was obtained before participation as approved by the University of Delaware Institutional Review Board.
Brenden was born at 34 weeks' gestation with prenatal encephalopathy and periventricular leukomalacia. At 5 months of age, his mother described him as experiencing difficulty making eye contact, holding his head up in prone or supported sitting, and rolling. By 7 months of age, he was diagnosed with CP and started physical, occupational, and speech therapy and early childhood education services every week in the home or at the ELC. He spent 9 hours per day at the ELC on average, including 7 hours per week of therapy and early childhood education.
At the start of this study, Brenden had full passive range of motion (ROM), limited active ROM, and difficulty initiating and isolating movements in all limbs, trunk, and neck. He required a tilted position when seated to maintain an upright head position. If not tilted, he could sustain an upright head position for a maximum of 1 to 2 minutes when highly motivated such as during mealtime. Spasticity in muscles around the large joints of his arms and legs was graded a 2+ on the Modified Ashworth Scale32 indicating more marked increased tone through most of the ROM, but affected parts were easily moved.
Functionally, he was unable to roll, sit, crawl, or step without maximal assistance. In sitting with maximum external trunk support, he could reach upward to the chest level with both arms with maximum verbal cuing for motivation. He could produce a palmer grasp with thumb adducted in the palm with both hands. His upper and lower extremity functions were classified as Level III of the Manual Ability Classification System (MACS)33 indicating difficulty in handling objects and requiring assistance to prepare and/or modify activities; and Level IV of the Gross Motor Function Classification System34 indicating an adult's assistance was required for mobility and mostly relying on wheeled mobility, which in Brenden's case was a stroller.
His EI team, including his mother, agreed that his primary limitation was his movement and mobility. The team was very concerned that he was becoming frustrated because he could not move, explore, and play. His mother expressed interest in finding a way that he could move on his own. His awareness of and attempts at interaction with objects and family during our initial screening observations led us to believe that a modified toy car would have positive effects on his mobility and socialization.
DESCRIPTION OF INTERVENTION
The 15-week study period included the following assessments: one home visit during the 1-week baseline period, 12 weekly home visits during the intervention period with the toy car, and 1 home visit during the 2-week postintervention period. Specifically, the baseline period home visit included car modifications, a home evaluation and a family questionnaire, a 20-minute videotaping of mobility and socialization measures administered by the research team, and the Pediatric Evaluation of Disability Inventory (PEDI) assessment administered by a physical therapist. Intervention period visits included both (1) a 30-minute driving training without videotaping and (2) 20 minutes of videotaping following the baseline protocol. On the final intervention period visit, the same physical therapist completed a PEDI and administered the family questionnaire. The postintervention visit included 20 minutes of videotaping of mobility and socialization and administration of the family questionnaire. Details of each period are briefly outlined in the next section.
Baseline Period (1 Week)
Before intervention, our team and Brenden's mother determined which car and which electrical and mechanical modifications met his current and anticipated needs. We selected a Fisher Price Mater (Fisher-Price Headquarters, East Aurora, NY) based on Brenden's body size and his need for trunk support. We modified the seating, steering, and drive systems. Specifically, we added a large, push switch (Jumbo Switch, Enabling Devices, Hawthorne, NY) so he could activate the car with 1 or both hands despite limited reaching and grasping abilities. We added a modified seating system of PVC pipe roll cage and T-bar as well as a seat belt, hip strap, foam noodles, and a towel so he could sit upright without leaning to the side and front (Figure 1a and 1b). These modifications were not “permanent” but rather were specific for his current abilities and were altered or removed as his abilities changed. Examples of other basic modifications have been previously reported.31
During the baseline period, we visited Brenden's home to determine which areas were safe for training. His family and our team agreed that training would occur only in the basement, living room, and neighborhood community spaces. During this baseline home visit, we also videotaped a 10-minute natural play session and a 10-minute car play session to determine initial values on mobility and socialization measures. During natural play, Brenden was provided opportunities to interact with toys and adults while supported in sitting on the floor by his mother. During car play, Brenden was provided with opportunities to drive to a target (eg, a toy or a person).
Intervention Period (3 Months)
The intervention included 2 major components: training and education.
Brenden's family provided him with daily opportunities and encouragement to use his car in their home and community for a minimum of 20 minutes per day, 5 days per week.35–37 Initially, the most common areas used by his family for car play were their home and front yard, the driveway, the gymnasium at the ELC, and a community park (Figure 1c). Brenden's physical therapist also provided similar opportunities as part of his ongoing EI sessions at the ELC. The general goals of these training activities involved driving to a target (eg, a ball) and engaging in play with someone (eg, catch and pass ball game).
During the first intervention period visit, the family was provided with an educational booklet and face-to-face training on the car's use (eg, fitting their child into the seat, how to charge the battery, how the switch worked), safety, and suggestions for initial activities. The family maintained a log of daily training time, location, general activities, and a scale indicating how much fun Brenden had during each day's driving. In addition, during each weekly visit, we engaged in 30 minutes of formal discussion with the family on the importance of daily mobility and how to create fun, goal-directed activities as part of daily play.
Initially, Brenden was asked to drive a certain distance (ie, from 3 feet to 5 feet) forward to an object, release his hand from the switch and reach for the target. Following the verbal prompt from the family or/and researcher, Brenden could consistently move the car forward but would not stop or turn to the left or right without physical assistance. At this phase, learning to turn was not an appropriate goal for him given his limited muscle strength and the bilateral coordination needed to hold and turn the steering wheel. We could not change the steering wheel to a joystick due to the lack of a power connection between the steering wheel and the tires. We emphasized the importance of parental supervision, as one would supervise any young child.
Postintervention (2 Weeks)
At the end of the 3-month intervention period, a physical therapist completed the PEDI and we removed the car for 2 weeks. After the 2 weeks, we completed a home visit and videotaped a 10-minute natural play and 10-minute car play session to assess Brenden's mobility and socialization.
Videos of the 20 minutes of testing were coded for outcome measures. We used measures of mobility and socialization, as well as 1 standardized, functional test (ie, the PEDI) to track Brenden's functional performances. We also used 3 questionnaires of family perceptions on mobility and an activity log after every day's driving and play. The following measures were obtained via video coding of the 10-minute car play and 10-minute natural play conditions.
- Driving categories (time in seconds)
- Independent mobility: When Brenden drove the car by independently initiating switch contact without adult assistance.
- Assisted mobility: When Brenden independently drove the car after an adult initiated switch contact.
- Caregiver mobility: When Brenden drove the car with an adult's hand directly on top of his hand.
- Visual attention to switch: The number of times that Brenden looked at the switch during the 10-minute driving session.
- Stopping categories (the number of times divided by total times target was presented)
- Independent stop: When Brenden independently moved his hand off the switch and made the car stop within 1 car length of the target.
- Stops with verbal cues: When Brenden moved his hand off the switch only after verbal cues.
- Stops with tactile contacts: When Brenden moved his hand off the switch only after tactile cues (eg, adult touching his hand or moving his hand off the switch).
- Reaching for toy/adult: The number of times Brenden extended his arms to interact with an adult such as to catch a ball.
- Facial expression: The number of positive expression such as smiling and laughing.
- Vocalization: The number of times that Brenden vocalized including grunting, shouting, and vowel-type sounds (eg, ee, i, ah, oo, u).
Spontaneous Family Interaction
To capture basic changes in family dynamics, we coded the duration that his family spontaneously interacted with him during the 10-minute car play during each visit.
Standardized, Functional Measure
The PEDI,38 a set of tests to measure children's performance of basic skills and the level of assistance or adaptation required, including self-care, mobility, and social functions, was used. The PEDI has established concurrent and construct validity and internal consistency for children with disabilities.39 The PEDI was administered by the clinical physical therapist at the beginning of the case study and 3 months later at study completion.
Daily Activity Log and Questionnaires
The daily activity log included daily training time, location, general activities, and the fun index. The fun index reflected the family's perception of how much Brenden enjoyed each driving activity, and ranged from 1 to 10, with a 10 indicating the highest level of fun. His family also kept a record of daily total training time (ie, total driving time), where they drove and what they did during training. The questionnaires (available online as Supplement Digital Content 1, at http://links.lww.com/PPT/A49) included a set of questions that examined the family's perceptions of power mobility devices and their effects on play and family interactions at home or other natural environments (eg, community locations).
DESCRIPTION OF OUTCOMES
Brenden drove straight forward independently without assistance on the first day of car use (Figure 2a). His visual attention to the switch decreased between intervention visit 1 and postintervention visit 1 with a period of increased attention in visits 10 to 12 (Figure 2b). After 12 weeks of training, when Brenden was 24 months of age, he could drive his car forward greater than 5 feet to reach a toy or interact with an adult. He independently stopped at the target greater than 50% of the time starting in the second week of the intervention (Figure 2c). By the end of the intervention, he could independently stop at the target 100% of the time and would consistently reach for the target object. Examples of new behaviors using the car in his home included (1) moving forward across a room and stopping to get a toy or participate in a game of catch or push a ball and (2) moving from room to room with physical assistance to turn right or left. When the training associated with this case study concluded, his goals included learning to grasp a horizontal bar installed on the steering wheel to assist turning while driving.
Compared to preintervention, the number of reaches increased throughout the intervention period during the Car Play condition, which involved dynamic play. Interestingly, the number of reaches did not increase during the natural play condition, which involved static sitting (Figure 3a). Positive facial expressions increased for both the natural and car play conditions (Figure 3b). Vocalizations also increased especially during the car play condition (Figure 3c). Overall, Brenden displayed more vocalizations to express positive emotions and/or to respond to adults later in training compared to the initial 2 weeks of training.
Brenden's family spontaneously increased their interactions with him in the car play condition during the intervention period (Figure 3d). This was especially evident during the last 4 intervention visits, in which his father played a major role throughout the 10 minutes of car play, including inviting him to drive over and play ball with him. The family noted that these were some of the first play sessions between Brenden and his father.
The PEDI results suggested an increase in Brenden's functional mobility and functional socialization with no clear change in self-care (Figure 4a) or caregiver assistance (Figure 4b).
Daily Activity Log and Questionnaires
The family's compliance and Brenden's level of fun remained high throughout the study. Brenden spent time in his car each week except for some days when he was sick (total home activity time: 1150 minutes for a total of 39 days; the compliance rates: 65%). From the activity log, the duration varied from 0 minutes to 50 minutes per day (mean 19 ± 0.13 minutes) due to weather and Brenden's tolerance. Popular training environments included his home (inside, driveway, street), his grandmother's home, the ELC gymnasium, and a neighborhood park. His daily Fun Index was 9 or 10 for most of the driving sessions (mean, 9 ± 1.6).
From the 3 questionnaires of family perception on mobility, the family's understanding of Brenden's abilities appeared to increase through this intervention. The family commented that the use of the modified toy car brought more fun and allowed greater flexible use across different indoor and outdoor settings as compared to other mobility devices (eg, gait trainer). Brenden started to roll, demonstrate a modified crawl, and walk with his mother's assistance at home. The family also learned how to modify the device themselves based on Brenden's needs. They also commented that he was a quick learner who could be more independent and could learn to adapt to his environment in daily life.
Ride-on toy cars are popular recreational vehicles for children with typical development worldwide. Modifying these cars for children with typical development is also an increasingly popular hobby for adults as reflected by an array of wiring diagrams, video examples, and “how to” instructions on specialized Web sites (Modified Power Wheels, http://http://www.youtube.com/channel/UCUJvxs5-iv1MDkL3WL9lN0Q/featured). Moreover, there is even a national racing series involving adults driving modified ride-on cars (Power Wheel Series, http://www.powerracingseries.org).
To the best of our knowledge, this case report is the first formal description of the use of a modified ride-on car to provide opportunities for mobility, socialization, and fun within the home and community for a young child with severe neuromotor impairments. Our findings are particularly encouraging considering that Brenden would not typically be considered an “ideal candidate” for traditional powered mobility, given his young age, communication limitations, and upper extremity motor impairments. This report joins and extends the increasing evidence supporting early powered mobility to increase independent exploration for optimal development in young children.14,15,19,20,23,25,40
The effect of modified car use in this report is most clearly seen when Brenden's mobility and socialization are compared before and during the intervention period. Before getting his car, Brenden had no independent mobility and little if any motivating opportunities to use his upper extremities, maintain an upright head position, or vocalize. He was unable to roll, sit, crawl, or step without maximum assistance of one adult. Similarly, he had limited socialization time (ie, play) with adults and less so with his highly active peer group. In contrast, within the first car training session, he learned that pressing the switch moved his car. Within the first 2 weeks of driving practice at home, he held an upright head position while he was independently moving and stopping his car to interact with a toy or adult. Moreover, during training, Brenden participated in play in his car both at home and in various community spaces such as the park, playground, and the ELC gymnasium. Family and therapists confirmed that these were his first experiences of independent mobility, socialization, and play. As such, these events may have, at least in part, triggered the increase in spontaneous interactions between Brenden and his family.
Formal studies can now build on this case report to quantify the effects of this new power mobility option. Three factors that we believe are important to include in future studies: (1) effects of powered mobility on body structure/function and overall development, (2) adaptive car modifications, and (3) family-centered intervention within natural environments. First, Brenden's physical therapist observed that he increased his upright head and trunk position and performed more head and arm movements in the car as compared to out of the car. This suggests that the act of driving the ride-on car both required and motivated increased active range of motion and/or control. Also, Brenden's improved PEDI scores suggested that the regular use of a ride-on car might prompt positive developmental changes. Formal studies should focus on changes across the ICF spectrum, as these cars may be effective at improving body structure/function components while simultaneously improving mobility and participation. Second, our seating modifications were flexible enough to provide a continuum of physical support. For example, as Brenden learned the concept of “press and go,” we would temporarily reduce his head and trunk supports to challenge his postural control and endurance for a portion of a session. We could then readily provide full support as needed when Brenden wanted to focus on mobility without a head/trunk challenge. Flexible modifications extend the utility of these cars to address goals across ICF components. Finally, the toy qualities and easy transportation likely contributed to the high levels of family compliance with daily play within a range of natural environments. Important findings would emerge from future studies comparing commercial power chairs with ride-on cars in terms of performance; inclusion in natural environments, perceptions of families, professionals and community, and financial considerations could be outlined in a comprehensive cost-benefit analysis.
In conclusion, the results from this case study join other work suggesting that children younger than 2 years can learn to use a powered mobility device and benefit from that use.15,19,23 We believe that ride-on cars provide similar benefits to children with and without special needs: opportunities for fun, mobility, socialization, movement, and a host of other developmentally important aspects of childhood. The opportunity now exists to quantify the range of effects such as those related to peer socialization and cognitive measures and body structure/function goals involving the neural, muscular, and skeletal systems.
We thank the participating family, the administration, and teachers of the University of Delaware Early Learning Center, David Glanzman, Manasa Sridhar, Lisa George, and Dr Sam Logan for their support of the ride-on toy car project.
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