Precision measurement of rehabilitation interventions-a secondary analysis of motor error in a clinical trial with young children with cerebral palsy.

Introduction: The delivery of precision medicine in rehabilitation will require not only precise measurement of participant response, but also precise measurement of the "ingredients" of intervention and their dose. As an example, we report the measurement of motor error in two treatment groups from a randomized controlled trial in toddlers (mean age 26.3 months) with cerebral palsy (CP). Our objective was to measure the type and amount of motor error during physical therapy sessions in young children with CP. Methods: Participants were stratified by motor function and age and randomly allocated to "conventional" physical therapy that generally prevented falls or to an intervention that encouraged error experience by not preventing falls (experimental group). Baseline motor and cognitive function were measured using the Gross Motor Function Measure-66 (GMFM-66) and Bayley 3 cognitive subscale (B3-C) prior to randomization. Randomly selected video recorded therapy sessions were manually coded to identify losses of balance defined as falls (child contacted floor), rescues (therapist prevented fall) or saves (child recovered their balance independently). Results: Average number of losses of balance per session were higher in the experimental group than the conventional group due to significantly greater falls. Saves were infrequent in both groups but were also significantly higher in the experimental group. Average number of rescues did not differ between groups. In the experimental group, greater frequency of falls was significantly related to GMFM-66. In both groups, greater frequency of saves was related to GMFM-66. Neither total losses of balance per session nor rescues were related to GMFM-66 in either group. There were no significant relationships between losses of balance and baseline cognition in either group, except greater frequency of saves was related to higher cognitive ability in the experimental group. Discussion: Our observations suggest that motor error experience is lower in toddlers with CP compared to peers with typical development but can be manipulated to higher doses of error during therapy sessions. Future work should investigate the relationship between type and amount of error experience and rehabilitation outcomes, as well as other "ingredients" of rehabilitation therapy. Tools to automate the precise measurement of intervention content are necessary for broad scale implementation.

Type and Distribution of Gross Motor Activity During Physical Therapy in Young Children With Cerebral Palsy.

OBJECTIVE: Physical therapists routinely deliver and prescribe motor practice to improve function. The ability to select optimal practice regimens is limited by a current lack of detail in the measurement of motor practice. The objective of this study was to quantify the type, amount, and timing of gross motor practice during physical therapist sessions. METHODS: A secondary video coding analysis of physical therapist sessions from the iMOVE clinical trial (NCT02340026) in young children with cerebral palsy (CP) was conducted. The 37 children who completed the treatment phase were included (mean age = 22.1 months). Children could initiate pulling to stand but were unable to walk. Videos of randomly selected therapy sessions were coded for gross motor activity (422 videos total). The 10 gross motor activity codes included lying, sitting, four point, crawling, kneeling, knee walking, standing, walking, transitions between floor postures, and transitions to/from an upright posture. Twenty percent of each video was double coded for reliability. Time per session, number of bouts, and median time per bout were calculated for each gross motor activity and for 2 aggregate measures: movement time and upright time. RESULTS: Participants spent more than half of therapy time in sitting and standing combined (60.3%). Transitions occurred more frequently than any other motor activity (49.3 total transitions per session). Movement time accounted for 16.3% of therapy time. Upright time accounted for 53.3% of therapy time. CONCLUSIONS: Critical practice time to gain motor skill is not equivalent to chronological time or time spent in therapy. Toddlers with CP spent a small amount of therapy time moving. Future work should explore the relations between motor practice and rehabilitation outcomes. IMPACT: Physical therapists are ideally suited to detail the content of motor practice and ultimately to prescribe optimal patterns of motor practice. We report the characteristics of gross motor practice during therapy in children with CP.

A new methodological approach to characterize selective motor control in children with cerebral palsy.

Introduction: Despite being a primary impairment in individuals with cerebral palsy (CP), selective motor control (SMC) is not routinely measured. Personalized treatment approaches in CP will be unattainable without the ability to precisely characterize the types and degrees of impairments in motor control. The objective of this study is to report the development and feasibility of a new methodological approach measuring muscle activation patterns during single-joint tasks to characterize obligatory muscle co-activation patterns that may underly impaired SMC. Methods: Muscle activation patterns were recorded during sub-maximal voluntary isometric contraction (sub-MVIC) tasks at the hip, knee, and ankle with an interactive feedback game to standardize effort across participants. We calculated indices of co-activation, synergistic movement, mirror movement, and overflow (indices range 0-2, greater scores equal to greater impairment in SMC) for each isolated joint task in 15 children - 8 with typical development (TD) (mean age 4.7 ± 1.0 SD years) and 7 with CP (mean age 5.8 ± 0.7 SD years). Indices were compared with Mann-Whitney tests. The relationships between the indices and gross motor function (GMFM-66) were examined with Pearson's r. Results: Mean indices were higher in the CP vs. the TD group for each of the six tasks, with mean differences ranging from 0.05 (abduction and plantarflexion) to 0.44 (dorsiflexion). There was great inter-subject variability in the CP group such that significant group differences were detected for knee flexion mirroring (p = 0.029), dorsiflexion coactivation (p = 0.021), and dorsiflexion overflow (p = 0.014). Significant negative linear relations to gross motor function were found in all four indices for knee extension (r = -0.56 to -0.75), three of the indices for ankle dorsiflexion (r = -0.68 to -0.78) and in two of the indices for knee flexion (r = -0.66 to -0.67), and ankle plantarflexion (r = -0.53 to -0.60). Discussion: Indices of coactivation, mirror movement, synergy, and overflow during single-joint lower limb tasks may quantify the type and degree of impairment in SMC. Preliminary concurrent validity between several of the indices of SMC and gross motor function was observed. Our findings established the feasibility of a new methodological approach that quantifies muscle activation patterns using electromyography paired with biofeedback during single-joint movement.

Motor training for young children with cerebral palsy: A single-blind randomized controlled trial.

AIM: To compare the effect of iMOVE (Intensive Mobility training with Variability and Error) therapy with dose-matched conventional therapy on gross motor development and secondary outcomes in young children with cerebral palsy. METHOD: This single-blind, randomized controlled trial included repeated assessments of gross motor function (using the Gross Motor Function Measure) and secondary outcomes during a 12- to 24-week intervention phase and at three follow-up points after treatment. Treatment was delivered three times per week in both groups. Forty-two children aged 12 to 36 months were stratified by age and motor function to ensure equivalence between groups at baseline. RESULTS: Thirty-six children completed treatment and follow-up phases. Treatment fidelity was high and adherence was equivalent between groups (77.3% conventional therapy, 76.2% iMOVE). There were no group differences on the primary (gross motor function after 12 weeks p = 0.18; after 24 weeks p = 0.94) or any secondary (postural control p = 0.88, caregiver satisfaction p = 0.52, child engagement p = 0.98) measure after treatment or at the follow-up points. However, one-third of total participants exceeded predicted change after 12 weeks and 77% exceeded predicted change after 24 weeks of treatment. INTERPRETATION: Our observations indicate a potential dose-response effect of rehabilitation therapy. We further demonstrated that individual therapeutic ingredients can be manipulated. When delivered consistently, both iMOVE and conventional therapy interventions might both be more effective than standard care. WHAT THIS PAPER ADDS: Those receiving iMOVE therapy demonstrated more independent practice time, error, and child-initiation than those receiving the dose-matched control. iMOVE therapy was not superior to the control (conventional physical) therapy. Most participants exceeded predicted change after 24 weeks of treatment.

The relationship between family empowerment and fine motor, gross motor and cognitive skills in young children with cerebral palsy.

BACKGROUND: Family empowerment in families of young children with cerebral palsy (CP) is an important consideration because the first few years of life can be overwhelming for parents. The purpose of this research was to investigate the relationship between family empowerment, fine motor (FM), gross motor (GM) and cognitive development in children with CP who were under 3 years of age. METHODS: Forty-one children with a mean age of 23.8 months participated in this study. The Family Empowerment Scale (FES) was completed by the participants' parents, whereas the FM, GM and cognitive subscales of the Bayley Scales of Infant and Toddler Development Third edition (B-III) were administered by physical therapists. RESULTS: Statistically significant positive correlations were found between the FES total and B-III raw scores for FM, GM and cognitive subscales with coefficients ranging from 0.35 to 0.41. Significant relationships were also found between the FES Community subscale and the B-III FM, GM and cognitive subscales. CONCLUSIONS: This study provides evidence of a relationship between family empowerment and FM, GM and cognitive abilities in young children with CP, with a greater severity of impairments related to lower levels of caregiver empowerment.

Unweighting infants reveals hidden motor skills.

We investigated the role of rate limiting factors in development using walking as a model system. The achievement of bipedal posture and locomotion are among the most significant achievements in an infant's first year, with poor balance and weak muscles long proposed as the rate limiting factors. Compensating for either may reveal upright motor skill that has not yet emerged in the infant's natural repertoire. To probe this question, we unweighted prewalking infants and measured their performance in various standing and walking behaviors while unweighted compared to baseline. Our secondary objective was to determine if the influence of unweighting was related to infants' locomotor experience. Infants stood unsupported for longer durations with 20% or 40% unweighting. Infants took more independent steps and more steps with one hand held with 40% unweighting. No differences in transition to/from standing were observed. Locomotor experience was related to the influence of unweighting during cruising and walking with a push toy. This is the first report of more advanced motor skills-longer periods of unsupported standing and the emergence of independent walking-revealed by unweighting infants. We interpret our observations to suggest that the refinement of motor control needed to support bipedal posture and locomotion precedes the functional emergence of these skills in infants. In other words, the musculoskeletal components required for walking are slower to develop than the neurological factors - and consequently may be the rate limiters. We further suggest that training regimens including unweighting should be explored in infants with motor delays.

The Use of Dynamic Weight Support with Principles of Infant Learning in a Child with Cerebral Palsy: A Case Report.

AIMS: Typical infant movement is characterized by a high degree of motor exploration, error, and variability. However, children with cerebral palsy (CP) often cannot create these experiences due to their neuromotor impairments. The purpose of this case study is to describe a 6-month course of physical therapy (PT) incorporating principles of infant motor learning using dynamic weight support (DWS) in a child with CP. METHODS: The child was a 27-month-old girl with diplegic CP who functioned at Gross Motor Function Classification System Level IV. The child received 68 PT sessions over a six-month period. DWS was used during therapy to encourage motor practice. The therapy area was arranged to encourage active exploration, motor variability, and error experience. Gross motor function, postural control, parent perception of performance, and parent satisfaction were measured before, during, and after the course of therapy. RESULTS: Gross motor function increased during the treatment beyond the level predicted from natural progression. Postural control fluctuated and demonstrated no appreciable improvement. Parent-perceived performance and satisfaction improved on three of four goals. CONCLUSIONS: Using DWS to incorporate principles of infant learning may have facilitated the development of gross motor skills in a child with diplegic CP.

The relationship between the Family Empowerment Scale and Gross Motor Function Measure-66 in Young Children with cerebral palsy.

BACKGROUND: Cerebral palsy (CP) is the most common cause of motor disability in children. A concept to consider in order to meet the needs of children with CP and their families is family empowerment. Family empowerment can be defined as the process by which families acquire the skills, knowledge and resources to allow them to gain control and improve the quality of their lives. The relationship between gross motor function and family empowerment may be important because children with CP vary so widely in their ability to perform motor skills, which may affect their family's levels of empowerment. The purpose of this research was to investigate the relationship between the Family Empowerment Scale (FES) and Gross Motor Function Measure-66 (GMFM-66) in children with CP who were under 3 years of age. METHODS: Forty-one children with a mean age of 23.8 months participated in this study. The FES was completed by the participants' parents or regular caregivers and includes a total score and subscales of empowerment in the family, in service situations and in community/political environments. The GMFM-66 was administered by a physical therapist and consists of a total score of gross motor function (GMFM-66) and subscores for Dimension B (sitting), Dimension C (crawling and kneeling), Dimension D (standing) and Dimension E (walking, running and jumping). RESULTS: Statistically significant positive correlations were found between the FES total and GMFM (total score and Dimensions B-E) with coefficients varying from 0.43-0.62. Significant relationships were also found between most subscales of the FES and the GMFM-66. CONCLUSIONS: This study provides evidence of a relationship between family empowerment and gross motor function in young children with CP and suggests that caregivers of children with higher gross motor function report higher levels of self-efficacy.

Construct Validity of the Early Clinical Assessment of Balance in Toddlers with Cerebral Palsy: Brief Report.

Purpose: The purpose of this research was to investigate differences in Early Clinical Assessment of Balance (ECAB) scores within children with cerebral palsy (CP) with different Gross Motor Function Classification System (GMFCS) levels and between children with CP and typical development (TD) who are under three years of age.Methods: The ECAB was administered to fifty children (13 with TD, 16 with GMFCS level II, 11 with GMFCS level III, 10 with GMFCS level III).Results: The group of children of TD had significantly higher scores than all groups of children with CP. There were significant differences in ECAB within the groups of children with CP with different GMFCS levels.Conclusion: The results of this study support the construct validity of the ECAB as a measure of postural control in children under three years of age with CP.

Linear and Nonlinear Measures of Postural Control in a Toddler With Cerebral Palsy: Brief Report.

PURPOSE: The purpose of this study was to describe changes in linear and nonlinear measures of postural control along with motor outcomes in a young child with cerebral palsy. SUMMARY OF KEY POINTS: Posturography in sitting and standing, the Gross Motor Function Measure-66 (GMFM-66), and the Early Clinical Assessment of Balance (ECAB) were performed prior to, during, and after physical therapy. The child demonstrated independent sitting throughout the study and developed independent standing during the study. He made improvements in the GMFM-66 and ECAB throughout the study. Higher average values were found in all linear and nonlinear measures in standing when compared to sitting, which may indicate less predictable movement due to less experience with standing. RECOMMENDATIONS FOR CLINICAL PRACTICE: Greater variability and lower predictability in postural control likely reflect early stages of skill acquisition. Research is needed to understand the optimal levels of movement variability and predictability.

The responsiveness and validity of the Early Clinical Assessment of Balance in toddlers with cerebral palsy: Brief report.

Purpose: The Early Clinical Assessment of Balance (ECAB) is a measure of postural stability for children with cerebral palsy (CP). The purpose of this research was to investigate the relationship between the ECAB and Gross Motor Function Measure-66 (GMFM-66) and to determine the responsiveness of the ECAB in children with CP under three years of age. Methods: Twenty seven children (mean age of 25 months) participated. Data were collected before and after 3 and 6 months of physical therapy. Responsiveness was calculated using standardized response means (SRM). Results: Significant relationships were observed between the ECAB, GMFM-66 score (r = 0.87), and GMFM subscales (r = 0.63-0.86). A moderate effect size (SRM = 0.62) and a large effect size (SRM = 0.92) for the ECAB were found over the 3- and 6-month intervention periods, respectively. Conclusion: These results support the validity and responsiveness of the ECAB in young children with CP.