Jill C. Heathcock

Movement Training Advances the Emergence of Reaching in Infants Born at Less Than 33 Weeks of Gestational Age: A Randomized Clinical Trial

Background and Purpose: This study had 2 purposes: (1) to compare the emergence of reaching in infants born full-term and infants born at less than 33 weeks of gestational age and (2) to evaluate the effectiveness of a movement training program on the emergence of reaching in this preterm population. Participants: Twenty-six infants born at less than 33 weeks of gestational age and with a birth weight less than 2,500 g were randomly assigned to receive 20 minutes of daily movement training (PT-M group) or daily social training (PT-S group) and were compared with 13 infants born full-term (FT-S group). Methods: Reaching and hand-object interactions were tested every other week for 8 weeks. At each visit, infants were allowed six 30-second opportunities to contact a midline toy. Results: The FT-S and PT-M groups reached earlier and more consistently than the PT-S group. Specifically, the subjects in the FT-S group contacted the toy for longer durations and with an open, ventral surface of their hand. The PT-M group demonstrated increases in the number of hand-object contacts, the number of consistent reaches, and the percentage of time interacting with the toy and the surface of hand-object contact. Discussion and Conclusion: This project demonstrates that there are early gross motor skill differences in infants born at less than 33 weeks of gestational age. A caregiver-based daily training program, however, is effective at lessening some, but not all, of these differences over the short term.

A Path Model for Evaluating Dosing Parameters for Children With Cerebral Palsy

Dosing of pediatric rehabilitation services for children with cerebral palsy (CP) has been identified as a national priority. Establishing dosing parameters for pediatric physical therapy interventions is critical for informing clinical decision making, health policy, and guidelines for reimbursement. The purpose of this perspective article is to describe a path model for evaluating dosing parameters of interventions for children with CP. The model is intended for dose-related and effectiveness studies of pediatric physical therapy interventions. The premise of the model is: Intervention type (focus on body structures, activity, or the environment) acts on a child first through the family, then through the dose (frequency, intensity, time), to yield structural and behavioral changes. As a result, these changes are linked to improvements in functional independence. Community factors affect dose as well as functional independence (performance and capacity), influencing the relationships between type of intervention and intervention responses. The constructs of family characteristics; child characteristics (eg, age, level of severity, comorbidities, readiness to change, preferences); plastic changes in bone, muscle, and brain; motor skill acquisition; and community access warrant consideration from researchers who are designing intervention studies. Multiple knowledge gaps are identified, and a framework is provided for conceptualizing dosing parameters for children with CP.

Research Summit III Proceedings on Dosing in Children With an Injured Brain or Cerebral Palsy: Executive Summary

Children with brain injuries or cerebral palsy (CP) comprise a large percentage of pediatric clients served by physical therapists. There is no consensus on what the basic parameters should be for different treatment protocols. A very important parameter of intervention that is pivotal for treatment efficacy is dosing. Dosing decisions are complex. To date, the minimum doses for changing structure and function, activity, and participation in children with various disabilities are unknown. This article describes the process and outcomes of a research summit with the goals of: (1) fostering a critical debate that would result in recommendations for the development of large-scale, second-generation research proposals to address thresholds for effective dosing of interventions for children with brain injuries or CP and (2) enhancing the research capacity of pediatric physical therapists through collaborative research networks. The summit brought together an interdisciplinary cadre of researchers (physical therapists, basic and clinical scientists), representatives from funding agencies, and consumers to an intensive 2.5-day think tank. The summit targeted questions of treatment dosage related to 3 areas: practice and neuroplasticity, structure-behavior connections, and clinical trial design. The consensus was that the intervention must demonstrate some evidence of effectiveness before optimal dosing can be investigated. Constraint-induced movement therapy (CIMT) is used as an example of an intervention that has demonstrated effectiveness and that requires dosing-related research. Summit results, including factors that merit special consideration and recommendations for future dose-related studies, are highlighted. Physical therapy is an important service for children with physical disabilities, particularly those with an injured brain resulting in neuromotor impairments and functional limitations.1 These children typically have multiple health complications that often result in complex functional limitations and require extensive health care, education, and vocational training. The costs of interventions result in substantial financial and social challenges for families and society.2 …

Exploring Objects With Feet Advances Movement in Infants Born Preterm: A Randomized Controlled Trial

Background: Previous work has shown that full-term infants who were healthy contacted a toy with their feet several weeks before they did so with their hands and that movement training advanced feet reaching. Certain populations of preterm infants are delayed in hand reaching; however, feet reaching has not been investigated in any preterm population. Objective: The primary purpose of this study was to determine whether preterm infants born at less than 33 weeks of gestational age contacted a toy with their feet at 2 months of corrected age, before doing so with their hands, and whether movement training advanced feet reaching. Design: This study was a randomized controlled trial. Methods: Twenty-six infants born preterm were randomly assigned to receive daily movement training or daily social training. During the 8-week training period, the infants were videotaped in a testing session every other week from 2 to 4 months of age. Results: Both groups contacted the toy with their feet at 2 months of age during the first testing session prior to training, at an age when no infants consistently contacted the toy with their hands. After 8 weeks of training, the movement training group displayed a greater number and longer duration of foot-toy contacts compared with the social training group. Conclusions: These results suggest that movement experiences advance feet reaching as they do for hand reaching. For clinicians, feet-oriented play may provide an early intervention strategy to encourage object interaction for movement impairments within the first months of postnatal life. Future studies can build on these results to test the long-term benefit of encouraging early purposeful leg movements.

Motor characteristics of young children referred for possible autism spectrum disorder.

Purpose: To examine motor characteristics of children referred for evaluation for autism spectrum disorder (ASD) using the Bayley Scales of Infant and Toddler Development, Third Edition (BSID-III). Methods: BSID-III scores were collected through retrospective chart review for 30 children (mean age = 31.57 ± 6 months) admitted to an outpatient autism evaluation clinic. Results: Children referred to an ASD clinic demonstrated a mean delay of 6 months for gross motor skills and 8 months for fine motor skills. There were no differences in total score or item analysis in group comparisons of motor characteristics in young children who did or did not receive a diagnosis of ASD. Conclusions: These results suggest that a delay in fine and gross motor skills at an early age is a characteristic of infants referred to an ASD clinic. Furthermore, the BSID-III may not be sensitive enough to distinguish between referred children with and without ASD.

Neonatal stroke causes poor midline motor behaviors and poor fine and gross motor skills during early infancy.

Upper extremity movements, midline behaviors, fine, and gross motor skills are frequently impaired in hemiparesis and cerebral palsy. We investigated midline toy exploration and fine and gross motor skills in infants at risk for hemiplegic cerebral palsy. Eight infants with neonatal stroke (NS) and thirteen infants with typical development (TD) were assessed from 2 to 7 months of age. The following variables were analyzed: percentage of time in midline and fine and gross motor scores on the Bayley Scales of Infant Development (BSID-III). Infants with neonatal stroke demonstrated poor performance in midline behaviors and fine and gross motor scores on the BSID-III. These results suggest that infants with NS have poor midline behaviors and motor skill development early in infancy.

Shoulder and elbow joint power differ as a general feature of vertical arm movements

Consistent patterns of joint power underlie coordinated lower extremity behaviors such as running and walking. Recent work found that shoulder and elbow power consistently differed during reaching movements in the horizontal plane. Moreover, joint power during horizontal reaching appears correlated with motor cortical activity. It is not known if the feature of differential joint power extends to vertical plane reaches or to reaches of different movement conditions. The purpose of this study was to test for differential shoulder and elbow power during the acceleratory and deceleratory phases of fast and normal speed vertical reaches in sitting and supine positions. Our results suggest that shoulder and elbow power typically differed both within and across conditions. First, shoulder power values were positive or negative dependent largely on movement direction and movement phase. That is, for each direction and phase, the shoulder either generated or absorbed energy independent of speed or body position. Second, and unexpectedly, reaches of certain condition combinations had similar shoulder power magnitudes across directions. In contrast, elbow power values for each direction varied between positive and negative values depending on phase, speed and position, and no two condition combinations overlapped across directions. Third, as target direction, movement phase and body position varied, shoulder power at fast and normal speeds were linearly correlated, as was shoulder power in sitting and in supine. In contrast, elbow power was linearly correlated only between speeds. These results join other studies to suggest that the neuromotor control of the shoulder may be less complex as compared to the elbow as a general feature of reaching movements. This differential control has important implications for the study of reaching impairments in neurorehabilitation populations, and provides a potentially important variable in the study of cortical firing patterns.

Early childhood constraint therapy for sensory/motor impairment in cerebral palsy: a randomised clinical trial protocol

Introduction Cerebral palsy (CP) is the most common physical disability in childhood. It is a disorder resulting from sensory and motor impairments due to perinatal brain injury, with lifetime consequences that range from poor adaptive and social function to communication and emotional disturbances. Infants with CP have a fundamental disadvantage in recovering motor function: they do not receive accurate sensory feedback from their movements, leading to developmental disregard. Constraint-induced movement therapy (CIMT) is one of the few effective neurorehabilitative strategies shown to improve upper extremity motor function in adults and older children with CP, potentially overcoming developmental disregard. Methods and analysis This study is a randomised controlled trial of children 12–24 months corrected age studying the effectiveness of CIMT combined with motor and sensory-motor interventions. The study population will comprise 72 children with CP and 144 typically developing children for a total of N=216 children. All children with CP, regardless of group allocation will continue with their standard of care occupational and physical therapy throughout the study. The research material collected will be in the form of data from high-density array event-related potential scan, standardised assessment scores and motion analysis scores. Ethics and dissemination The study protocol was approved by the Institutional Review Board. The findings of the trial will be disseminated through peer-reviewed journals and scientific conferences. Trial registration number NCT02567630.

Perinatal stroke causes abnormal trajectory and laterality in reaching during early infancy

The developmental progression of reaching and early signs of upper extremity neglect is common concern for infants at risk for hemiparesis and cerebral palsy. We investigated the emergence of reaching and laterality in infants at risk for hemiplegic cerebral palsy. Eight infants with perinatal stroke (PS) and thirteen infants with typical development (TD) were assessed bimonthly from 2 to 7 months of age for 10 visits per infant. Reaching number and hand-toy contact duration were measured. Infants with PS demonstrated a linear trajectory of reaching behaviors with asymmetrical upper extremity performance. Infants with TD demonstrated a linear and quadratic trajectory of reaching behaviors and symmetrical upper extremity performance over the same age range. These results suggest that infants with PS have delay reaching and early signs of neglect not currently accounted for in clinical practice.

Invited Commentary on “Gastrocnemius-Soleus Muscle Tendon Unit Changes Over the First 12 Weeks of Adjusted Age in Infants Born Preterm”

Grant-Beuttler et al1 present an interesting report describing the measurement of gastrocnemius-soleus muscle tendon unit (MTU) lengths from term to 12 weeks of age in infants born preterm and infants born full term. This work joins that of other authors2 in suggesting that infants born preterm have a different developmental trajectory than infants born full term and they have identifiable and measurable impairments during early infancy. This study examined the differences in muscle-tendon tautness, length, and stretch over time. The authors note that a limitation of their study was the lack of measurements of knee flexion angle of newborn infants, both full term and preterm, to demonstrate extension limitations of the knee. Because the gastrocnemius is a 2-joint muscle, any degree of knee flexion may be important. It is very difficult to stretch the …