Gloria R. Gogola

Mutations in ECEL1 Cause Distal Arthrogryposis Type 5D

Distal arthrogryposis (DA) syndromes are the most common of the heritable congenital-contracture disorders, and ~50% of cases are caused by mutations in genes that encode contractile proteins of skeletal myofibers. DA type 5D (DA5D) is a rare, autosomal-recessive DA previously defined by us and is characterized by congenital contractures of the hands and feet, along with distinctive facial features, including ptosis. We used linkage analysis and whole-genome sequencing of a multiplex consanguineous family to identify in endothelin-converting enzyme-like 1 (ECEL1) mutations that result in DA5D. Evaluation of a total of seven families affected by DA5D revealed in five families ECEL1 mutations that explain ~70% of cases overall. ECEL1 encodes a neuronal endopeptidase and is expressed in the brain and peripheral nerves. Mice deficient in Ecel1 exhibit perturbed terminal branching of motor neurons to the endplate of skeletal muscles, resulting in poor formation of the neuromuscular junction. Our results distinguish a second developmental pathway that causes congenital-contracture syndromes.

Hand Dexterity in Children: Administration and Normative Values of the Functional Dexterity Test

PURPOSE To document normative values from the Functional Dexterity Test (FTD) for typically developing children and to optimize test administration and interpretation. METHODS A total of 175 typically developing children aged 3 to 17 years participated in the study. Children completed the 16-peg FDT with both hands, and elapsed time was recorded in seconds. Data were analyzed as 16/time, interpreted as speed (pegs per second). A linear regression analysis predicted speed from age and hand dominance. RESULTS Functional Dexterity Test speed increased linearly in typically developing children by 0.04 pegs/s for each year of age. This rate of increase was the same for dominant and nondominant hands. Dominant hands were faster than nondominant hands by 0.09 pegs/s at all ages. There was no sex difference. CONCLUSIONS This study provides age-specific normative values for functional dexterity in typically developing children in 2 formats: as a growth chart of FDT speed versus age and as a regression model that calculates expected speed given a childs age and tested hand dominance. Recommended pediatric modifications to the FDT are to use speed (pegs per second) instead of time (seconds) to report results, and to not assess penalties. The norms presented allow clinicians to compare both speed and rate of change over time of pediatric patients with typically developing children, which makes it possible to distinguish developmental change from intervention. TYPE OF STUDY/LEVEL OF EVIDENCE Diagnostic III.

Peg Restrained Intrinsic Muscle Evaluator (PRIME): Development, Reliability, and Normative Values of a Device to Quantify Intrinsic Hand Muscle Strength in Children

PURPOSE There is a need for objective measures of pediatric intrinsic hand muscle strength as the current standard, the manual muscle test, lacks sensitivity to clinically important changes in muscle strength. We report the development, reliability, and normative values of the Peg Restrained Intrinsic Muscle Evaluator (PRIME), a device that quantifies intrinsic hand muscle strength. METHODS Typically developing children, ages 4 to 16 years (n = 119), established normative values of intrinsic strength for thumb palmar abduction, thumb opposition, and index and small finger abduction. A subset of 30 children (15 boys, 15 girls), ages 7 to 16 years, determined inter-rater and intra-rater reliability. We calculated mean, standard deviation, intraclass correlation coefficients, and smallest detectable differences. RESULTS Normative results indicate that gender and age were significant predictors of strength. Although the dominant hand generated higher strength measurements on average, differences were not statistically significant. Mean index and small finger abduction strength was significantly lower than thumb abduction and opposition in both genders. Intraclass correlation coefficients ranged from 0.85 to 0.94 for inter-rater reliability and 0.88 to 0.98 for intra-rater reliability. Bland-Altman plots showed an even distribution across the zero line. CONCLUSIONS The PRIME device is a reliable tool for the quantification of intrinsic hand muscle strength in children. Age-specific and gender-specific normative values in typically developing children can serve as a future resource for clinicians treating pediatric hand or neuromuscular conditions.

Innovative evaluation of dexterity in pediatrics.

STUDY DESIGN Review paper. INTRODUCTION Hand dexterity is multifaceted and essential to the performance of daily tasks. Timed performance and precision demands are the most common features of quantitative dexterity testing. Measurement concepts such as rate of completion, in-hand manipulation and dynamic force control of instabilities are being integrated into assessment tools for the pediatric population. PURPOSE To review measurement concepts inherent in pediatric dexterity testing and introduce concepts that are infrequently measured or novel as exemplified with two assessment tools. METHODS Measurement concepts included in common assessment tools are introduced first. We then describe seldom measured and novel concepts embedded in two instruments; the Functional Dexterity Test (FDT) and the Strength-Dexterity (SD) Test. DISCUSSION The inclusion of novel yet informative tools and measurement concepts in our assessments could aid our understanding of atypical dexterity, and potentially contribute to the design of targeted therapy programs.

Perspectives on glenohumeral joint contractures and shoulder dysfunction in children with perinatal brachial plexus palsy

Shoulder joint deformities continue to be a challenging aspect of treating upper plexus lesions in children with perinatal brachial plexus palsy (PBPP). It is increasingly recognized that PBPP affects the glenohumeral joint specifically, and that abnormal scapulothoracic movements are a compensatory development. The pathophysiology and assessment of glenohumeral joint contractures, the progression of scapular dyskinesia and skeletal dysplasia, and current shoulder imaging techniques are reviewed.

Computer adaptive test approach to the assessment of children and youth with brachial plexus birth palsy.

This study examined the psychometric properties of item pools relevant to upper-extremity function and activity performance and evaluated simulated 5-, 10-, and 15-item computer adaptive tests (CATs). In a multicenter, cross-sectional study of 200 children and youth with brachial plexus birth palsy (BPBP), parents responded to upper-extremity (n = 52) and activity (n = 34) items using a 5-point response scale. We used confirmatory and exploratory factor analysis, ordinal logistic regression, item maps, and standard errors to evaluate the psychometric properties of the item banks. Validity was evaluated using analysis of variance and Pearson correlation coefficients. Results show that the two item pools have acceptable model fit, scaled well for children and youth with BPBP, and had good validity, content range, and precision. Simulated CATs performed comparably to the full item banks, suggesting that a reduced number of items provide similar information to the entire set of items.

Contribution of tactile dysfunction to manual motor dysfunction in type II diabetes.

Introduction: Changes in sensory and motor functions of the hand in type II diabetes (T2D) patients have been reported; there is speculation that these changes are driven by tactile dysfunction. The purpose of this study was to evaluate the effects of tactile feedback on manual function in T2D patients. Methods: T2D patients and healthy controls underwent median nerve blocks at the wrist and elbow. All participants underwent traditional timed motor evaluations, force dynamometry, laboratory‐based kinetic evaluations, and sensory evaluation. Results: Tactile sensation in the T2D group at baseline was found to be equivalent to tactile function of the control group after median nerve block. Traditional timed evaluation results were negatively impacted by anesthesia, but more sensitive kinetic measures were not impacted. Conclusions: These data suggest that mechanisms outside of tactile dysfunction play a significant role in motor dysfunction in T2D. Muscle Nerve 54: 895–902, 2016

Validity and reliability of the Functional Dexterity Test in children

STUDY DESIGN Clinical measurement study. INTRODUCTION The Functional Dexterity Test (FDT) has not been validated in children. PURPOSE OF THE STUDY To determine reliability and validity of the FDT in a pediatric population. METHODS Intraclass Correlation Coefficients (ICCs) were used to calculate interrater and test-retest reliability in typically developing children. Pearson correlation coefficients were used to compare FDT speed with the Jebsen-Taylor Hand Function Test (JHFT) and with 2 activities of daily living tasks to establish validity in children with congenital hand differences. RESULTS The FDT demonstrated excellent interrater (ICC, 0.99) and test-retest (ICC, 0.90) reliability. Pearson correlation coefficients exceeded 0.67 for JHFT subsets of fine dexterity and were all less than 0.66 for JHFT subsets of gross grasp. Correlations with the activities of daily living tasks were good to excellent. FDT speeds in TD children exceeded those of children with congenital hand differences (P < .001), demonstrating discriminant validity. DISCUSSION Children with congenital hand differences are often treated early in life, making it important to reliably assess hand function of these young children to distinguish developmental change from changes due to interventions. The FDT can reliably measure functional progress over time, help clinicians monitor the efficacy of treatment, and provide families realistic feedback on their childs progress. CONCLUSION The FDT is a valid and reliable instrument for the measurement of fine motor dexterity in children.

Mechanical Wheelchair Propulsion System for Patients With Arthrogryposis

Arthrogryposis is a congenital disorder characterized by extreme joint stiffness that inhibits strength and flexibility in upper and lower extremities. Cases vary in severity, but this research focuses on those in which patients require a wheelchair for mobility. Currently, two conventional designs exist: mechanical and electric wheelchairs. For most arthrogryposis patients, existing mechanical wheelchairs are insufficient for independent propulsion as their joints are severely impaired, prohibiting them from reaching the outer handrails on the wheels and expending enough force to propel and steer. Existing devices that improve the mechanical advantage of wheelchairs are insufficient for the needs of these patients who have very limited and specific ranges of motions, which are not compatible with the required force inputs. Though electric wheelchairs allow independent mobility, they are expensive to maintain and not easily portable, limiting their use by socioeconomically disadvantaged patients.Arthrogryposis patients require a lightweight, portable and durable mechanical wheelchair that takes advantage of the user’s specific strengths, and is easily maneuvered in all directions without assistance. A design is presented for a socioeconomically disadvantaged teenage client with arthrogryposis. After taking data regarding the ranges of motion and strength of the client, a new propulsion system was designed and retrofitted to a conventional wheelchair. Prototye I has been tested and a second-generation design which fits the needs of a wider audience suffering from arthrogryposis is presented.Copyright