Research conference summary from the 2014 International Task Force on -Related Disorders.

Objective: -related neurologic disorders encompass a broad range of phenotypes that extend well beyond initial phenotypic criteria associated with alternating hemiplegia of childhood (AHC) and rapid-onset dystonia parkinsonism.

Methods: In 2014, the Alternating Hemiplegia of Childhood Foundation hosted a multidisciplinary workshop intended to address fundamental challenges surrounding the diagnosis and management of individuals with -related disorders.

Results: Workshop attendees were charged with the following: (1) to achieve consensus on expanded diagnostic criteria to facilitate the identification of additional patients, intended to supplement existing syndrome-specific diagnostic paradigms; (2) to standardize definitions for the broad range of paroxysmal manifestations associated with AHC to disseminate to families; (3) to create clinical recommendations for common recurrent issues facing families and medical care providers; (4) to review data related to the death of individuals in the Alternating Hemiplegia of Childhood Foundation database to guide future efforts in identifying at-risk subjects and potential preventative measures; and (5) to identify critical gaps where we most need to focus national and international research efforts.

Alternating Hemiplegia of Childhood: Retrospective Genetic Study and Genotype-Phenotype Correlations in 187 Subjects from the US AHCF Registry.

Mutations in ATP1A3 cause Alternating Hemiplegia of Childhood (AHC) by disrupting function of the neuronal Na+/K+ ATPase. Published studies to date indicate 2 recurrent mutations, D801N and E815K, and a more severe phenotype in the E815K cohort. We performed mutation analysis and retrospective genotype-phenotype correlations in all eligible patients with AHC enrolled in the US AHC Foundation registry from 1997-2012.

Resistance strength training exercise in children with spinal muscular atrophy.

Introduction: Preliminary evidence in adults with spinal muscular atrophy (SMA) and in SMA animal models suggests exercise has potential benefits in improving or stabilizing muscle strength and motor function.

Methods: We evaluated feasibility, safety, and effects on strength and motor function of a home-based, supervised progressive resistance strength training exercise program in children with SMA types II and III. Up to 14 bilateral proximal muscles were exercised 3 times weekly for 12 weeks.

New therapeutic approaches to spinal muscular atrophy.

Bench to bedside progress has been widely anticipated for a growing number of neurodegenerative disorders. Of these, spinal muscular atrophy (SMA) is perhaps the best poised to capitalize on advances in targeted therapeutics development over the next few years. Several laboratories have achieved compelling success in SMA animal models using sophisticated methods for targeted delivery, repair, or increased expression of the survival motor neuron protein, SMN.

Reliability of the Modified Hammersmith Functional Motor Scale in young children with spinal muscular atrophy.

Introduction: The test-retest reliability of the Modified Hammersmith Functional Motor Scale (MHFMS) in children with spinal muscular atrophy (SMA) ≤30 months of age was assessed. The age at which typically developing children (TD) achieve maximum MHFMS scores was also studied.

Methods: Twenty-two children with SMA type II [mean age (SD) = 20 (5) months, range 9-30 months) were tested twice using the MHFMS.

Compound muscle action potential and motor function in children with spinal muscular atrophy.

Reliable outcome measures that reflect the underlying disease process and correlate with motor function in children with SMA are needed for clinical trials. Maximum ulnar compound muscle action potential (CMAP) data were collected at two visits over a 4-6-week period in children with SMA types II and III, 2-17 years of age, at four academic centers. Primary functional outcome measures included the Modified Hammersmith Functional Motor Scale (MHFMS) and MHFMS-Extend.

Alternating hemiplegia of childhood: early characteristics and evolution of a neurodevelopmental syndrome.

Objectives: Alternating hemiplegia of childhood is a predominantly sporadic neurodevelopmental syndrome of uncertain etiology. In more than 3 decades since its description, little progress has been made in understanding its etiology or in identifying effective treatments. In 1998, in collaboration with the Alternating Hemiplegia of Childhood Foundation, an international registry was established to help document clinical outcomes and promote research efforts.

Injury severity variables as predictors of WeeFIM scores in pediatric TBI: Time to follow commands is best.

After pediatric traumatic brain injury (TBI), early prognosis of expected function is important for optimizing care. The power of several common brain injury severity measures for predicting functional outcome in children with TBI was investigated; the severity variables studied were Glasgow Coma Scale (GCS) score, time to follow commands (TFC), duration of post-traumatic amnesia (PTA), and total duration of impaired consciousness (TFC+PTA). Outcome was assessed using the Functional Independence Measure for Children (WeeFIM) at discharge from inpatient rehabilitation (n = 120) and, in a subset of children, at 3 months following discharge.