Status of surface electromyography assessment as part of clinical gait analysis in the management of patients with cerebral palsy - Outcomes of a Delphi process.

Background: The assessment of gait disorders in patients with neuromotor conditions, such as cerebral palsy (CP), has been a focus of clinical and research attention, with electromyography (EMG) offering a nuanced understanding of neurological and neuromuscular disorders. However, the interpretation of EMG data in the context of gait analysis remains challenging due to the complexity of neuromotor dynamics and variability in assessment methodologies.

Research Question: To which consensus can we get in a group of experts in the fields of neurological and neuromuscular disorders, biomechanics, and clinical gait analysis to establish standardized protocols and a common language for the measurement and analysis of EMG data in gait disorders, particularly in people living with CP?

Methods: A three-round Delphi process was conducted from February to September 2023 to gather opinions of 53 experts on the use of surface EMG data during gait in the context of CP.

Short-term selective dorsal rhizotomy responders among children with bilateral cerebral palsy.

Aim: To identify the short-term effects of selective dorsal rhizotomy (SDR) on gait and clinical impairments in children with bilateral spastic cerebral palsy (CP) and subgroups based on baseline gait patterns.

Method: Eighty-nine children with bilateral spastic CP (55 males, mean age [SD] before SDR: 9 years 5 months [2 years 3 months]; Gross Motor Function Classification System level I: 18; II: 54; III: 17) received three-dimensional gait analyses at two time points (baseline and 1 year after SDR); their baseline gait patterns were classified. The analysis included the comparisons of (1) sagittal plane kinematic waveforms, the Gait Profile Score, and non-dimensional spatiotemporal parameters between the two time points, (2) the kinematic waveforms of both time points to those of typically developing children, and (3) composite impairment scores of spasticity, weakness, and selectivity between the two time points.

Effect of selective dorsal rhizotomy on neuromuscular symptoms, muscle morphology, and motor function in children with spastic cerebral palsy.

Aim: To investigate the effect of selective dorsal rhizotomy (SDR) on an integrated outcome set 1-year post-SDR, in a cohort of children with spastic cerebral palsy (CP).

Method: Fifteen children with bilateral spastic CP (median age 8 years 8 months [interquartile range 3 years 3 months], 11 males, four females, eight in Gross Motor Function Classification System (GMFCS) level II, seven in GMFCS level III) were measured pre- and 1-year post-SDR. Clinical scales and goniometry assessed plantar flexor spasticity, range of motion, strength, and selectivity.

Evaluation of the Working Mechanism of a Newly Developed Powered Ankle-Foot Orthosis.

Ankle-foot orthoses (AFOs) are commonly prescribed to children with cerebral palsy (CP). The conventional AFO successfully controls the first and second ankle rocker, but it fails to correct the third ankle rocker, which negatively effects push-off power. The current study evaluated a new powered AFO (PAFO) design, developed to address the shortcomings of the conventional AFO.

Repeatability of gait of children with spastic cerebral palsy in different walking conditions.

Three-dimensional gait analysis is the 'gold standard' for measurement and description of gait. Gait variability can arise from intrinsic and extrinsic factors and may vary between walking conditions. This study aimed to define the inter-trial and inter-session repeatability in gait analysis data of children with cerebral palsy (CP) who were walking in four conditions, namely barefoot or with ankle-foot orthosis (AFO), and overground or treadmill.

Markerless motion analysis to assess reaching-sideways in individuals with dyskinetic cerebral palsy: A validity study.

This study aimed to evaluate clinical utility of 2D-markerless motion analysis (2DMMA) from a single camera during a reaching-sideways-task in individuals with dyskinetic cerebral palsy (DCP) by determining (1) concurrent validity by correlating 2DMMA against marker-based 3D-motion analysis (3DMA) and (2) construct validity by assessing differences in 2DMMA features between DCP and typically developing (TD) peers. 2DMMA key points were tracked from frontal videos of a single camera by DeepLabCut and accuracy was assessed against human labelling. Shoulder, elbow and wrist angles were calculated from 2DMMA and 3DMA (as gold standard) and correlated to assess concurrent validity.

Combined translational and rotational perturbations of standing balance reveal contributions of reduced reciprocal inhibition to balance impairments in children with cerebral palsy.

Balance impairments are common in cerebral palsy. When balance is perturbed by backward support surface translations, children with cerebral palsy have increased co-activation of the plantar flexors and tibialis anterior muscle as compared to typically developing children. However, it is unclear whether increased muscle co-activation is a compensation strategy to improve balance control or is a consequence of reduced reciprocal inhibition.

A Comparison of the Immediate Effects of Verbal and Virtual Reality Feedback on Gait in Children with Cerebral Palsy.

Different types of feedback are used during gait training in children with cerebral palsy (CP), including verbal (VB) and virtual reality (VR) feedback. Previous studies on VR feedback showed positive effects on the targeted gait parameter. However, both positive and negative side effects on other parameters were seen as well.

Gait classification for growing children with Duchenne muscular dystrophy.

Classifying gait patterns into homogeneous groups could enhance communication among healthcare providers, clinical decision making and clinical trial designs in boys with Duchenne muscular dystrophy (DMD). Sutherland's classification has been developed 40 years ago. Ever since, the state-of-the-art medical care has improved and boys with DMD are now longer ambulatory.

Histological analysis of the medial gastrocnemius muscle in young healthy children.

Histological data on muscle fiber size and proportion in (very) young typically developing (TD) children is not well documented and data on capillarization and satellite cell content are also lacking. This study investigated the microscopic properties of the medial gastrocnemius muscle in growing TD children, grouped according to age and gender to provide normal reference values in healthy children. Microbiopsies of the medial gastrocnemius (MG) muscle were collected in 46 TD boys and girls aged 2-10 years subdivided into 4 age groups (2-4, 4-6, 6-8 and 8-10 years).

The relationship between manual ability, dystonia and choreoathetosis severity and upper limb movement patterns during reaching and grasping in children and young adults with dyskinetic cerebral palsy.

Introduction: Impaired upper limb movements are a key feature in dyskinetic cerebral palsy (CP). However, information on how specific movement patterns relate to manual ability, performance and underlying movement disorders is lacking. Insight in these associations may contribute to targeted upper limb management in dyskinetic CP.

Defining tibial anterior muscle morphology in first-ever chronic stroke patients using three-dimensional freehand ultrasound.

Background: Drop foot is common post-stroke, elevating fall risks and mobility limitations. It is caused by weakness and lack of control of the tibialis anterior muscle (TA), for which various rehabilitation treatments are used. A reliable objective estimate of changes in TA muscle morphology and composition can enhance treatment optimization.

Identification of Neural and Non-Neural Origins of Joint Hyper-Resistance Based on a Novel Neuromechanical Model.

Joint hyper-resistance is a common symptom in neurological disorders. It has both neural and non-neural origins, but it has been challenging to distinguish different origins based on clinical tests alone. Combining instrumented tests with parameter identification based on a neuromechanical model may allow us to dissociate the different origins of joint hyper-resistance in individual patients.

Short-Term Effects of Botulinum Toxin-A Injection on the Medial Gastrocnemius Histological Features in Ambulant Children with Cerebral Palsy: A Longitudinal Pilot Study.

Botulinum toxin-A (BoNT-A) injection is known to exert beneficial effects on muscle tone, joint mobility and gait in children with cerebral palsy (CP). However, recent animal and human studies have raised the concern that BoNT-A might be harmful to muscle integrity. In CP-children, the impact of BoNT-A on muscle structure has been poorly studied, and inconsistent results have been reported.

Histological analysis of the gastrocnemius muscle in preschool and school age children with cerebral palsy compared with age-matched typically developing children.

Inconsistent alterations in skeletal muscle histology have been reported in adolescents with cerebral palsy (CP) and whether alterations are present in young children and differ from older children is not yet known. This study aimed to define histological alterations in the medial gastrocnemius (MG) of ambulant CP (gross-motor classification system, GMFCS I-III) stratified in two age groups (preschool children, PS: 2-5 and school age children, SA: 6-9-yr old) compared with age-matched typically developing (TD) children. We hypothesized that alterations in muscle microscopic properties are already present in PS-CP and are GMFCS level specific.

Three-dimensional freehand ultrasonography to measure muscle volume of the lumbar multifidus: Reliability of processing technique and validity through comparison to magnetic resonance imaging.

There is a growing interest in muscle characteristics of the lumbar multifidus related to low back pain, but findings between studies are inconsistent. One of the issues explaining these conflicting findings might be the use of two-dimensional measures of cross-sectional area and thickness of the lumbar multifidus in most studies, which might be a suboptimal representation of the entire muscle volume. A three-dimensional volumetric assessment, combined with standardized imaging and processing measurement protocols, is highly recommended to quantify spinal muscle morphology.

Fine-needle percutaneous muscle microbiopsy technique as a feasible tool to address histological analysis in young children with cerebral palsy and age-matched typically developing children.

Cerebral palsy (CP) is a heterogeneous group of motor disorders attributed to a non-progressive lesion in the developing brain. Knowledge on skeletal muscle properties is important to understand the impact of CP and treatment but data at the microscopic levels are limited and inconsistent. Currently, muscle biopsies are collected during surgery and are restricted to CP eligible for such treatment or they may refer to another muscle or older children in typically developing (TD) biopsies.

Reduced reciprocal inhibition during clinical tests of spasticity is associated with impaired reactive standing balance control in children with cerebral palsy.

Background: Joint hyper-resistance is a common symptom in cerebral palsy (CP). It is assessed by rotating the joint of a relaxed patient. Joint rotations also occur when perturbing functional movements.

Longitudinal trajectory of medial gastrocnemius muscle growth in the first years of life.

Aim: To define the longitudinal trajectory of gastrocnemius muscle growth in 6- to 36-month-old children with and without spastic cerebral palsy (SCP) and to compare trajectories by levels of gross motor function (Gross Motor Function Classification System, GMFCS) and presumed brain-lesion timing.

Method: Twenty typically developing children and 24 children with SCP (GMFCS levels I-II/III-IV = 15/9), were included (28/16 females/males; mean age at first scan 15.4 months [standard deviation 4.

Muscle morphology and architecture of the medial gastrocnemius between typically developing children with different ancestral background.

Muscle ultrasonography is frequently used to improve the understanding of musculoskeletal impairments in children with spastic cerebral palsy (SCP). So far, most studies on muscle morphology and architecture have included typically developing children and children with SCP with similar ancestry, being mainly Caucasian. Less is known about differences in muscle morphology between children with different ancestral backgrounds.

Botulinum Toxin Treatment of Adult Muscle Stem Cells from Children with Cerebral Palsy and hiPSC-Derived Neuromuscular Junctions.

Botulinum neurotoxin type-A (BoNT) injections are commonly used as spasticity treatment in cerebral palsy (CP). Despite improved clinical outcomes, concerns regarding harmful effects on muscle morphology have been raised, and the BoNT effect on muscle stem cells remains not well defined. This study aims at clarifying the impact of BoNT on growing muscles (1) by analyzing the in vitro effect of BoNT on satellite cell (SC)-derived myoblasts and fibroblasts obtained from medial gastrocnemius microbiopsies collected in young BoNT-naïve children (t0) compared to age ranged typically developing children; (2) by following the effect of in vivo BoNT administration on these cells obtained from the same children with CP at 3 (t1) and 6 (t2) months post BoNT; (3) by determining the direct effect of a single and repeated in vitro BoNT treatment on neuromuscular junctions (NMJs) differentiated from hiPSCs.

Intensive Therapy of the Lower Limbs and the Trunk in Children with Bilateral Spastic Cerebral Palsy: Comparing a Qualitative Functional and a Functional Approach.

Few studies have examined the effect of intensive therapy on gross motor function and trunk control in children with cerebral palsy (CP). This study evaluated the effects of an intensive burst of therapy on the lower limbs and trunk by comparing qualitative functional and functional approaches. This study was designed as a quasi-randomized, controlled, and evaluator-blinded trial.

Altered upper limb kinematics in individuals with dyskinetic cerebral palsy in comparison with typically developing peers - A statistical parametric mapping study.

Background: Dyskinetic cerebral palsy (DCP) is clinically characterized by involuntary movements and abnormal postures, which can aggravate with activity. While upper limb movement variability is often detected in the clinical picture, it remains unknown how movement patterns of individuals with DCP differ from typically developing (TD) peers.

Research Question: Do individuals with DCP show i) higher time-dependent standard deviations of upper limb joint angles and ii) altered upper limb kinematics in time and/or amplitude during functional upper limb tasks in comparison with TD individuals?

Methods: Three-dimensional upper limb movement patterns were cross-sectionally compared in 50 individuals with and without DCP during three functional tasks: reach forward (RF), reach and grasp vertical (RGV) and reach sideways (RS).

Morphological Medial Gastrocnemius Muscle Growth in Ambulant Children with Spastic Cerebral Palsy: A Prospective Longitudinal Study.

Only cross-sectional studies have demonstrated muscle deficits in children with spastic cerebral palsy (SCP). The impact of gross motor functional limitations on altered muscle growth remains unclear. This prospective longitudinal study modelled morphological muscle growth in 87 children with SCP (age range 6 months to 11 years, Gross Motor Function Classification System [GMFCS] level I/II/III = 47/22/18).

Reliability of 3D freehand ultrasound to assess lower limb muscles in children with spastic cerebral palsy and typical development.

This study investigated the reliability of 3-dimensional freehand ultrasound (3DfUS) to quantify the size (muscle volume [MV] and anatomical cross-sectional area [aCSA]), length (muscle length [ML], tendon length [TL], and muscle tendon unit length [MTUL]), and echo-intensity (EI, whole muscle and 50% aCSA), of lower limb muscles in children with spastic cerebral palsy (SCP) and typical development (TD). In total, 13 children with SCP (median age 14.3 (7.