Symptoms and General Pathology

All Conditions

Nervous System Diseases

Neoplasms

Diseases and Abnormalities at or Before Birth

Skin and Connective Tissue Diseases

Rare Diseases

Sclerosis

Epilepsy

Movement Disorders

Tuberous Sclerosis

Brain Diseases

Central Nervous System Diseases

Hamartoma

Neoplasms, Multiple Primary

Syndrome

Neoplastic Syndromes, Hereditary

Congenital Abnormalities

Malformations of Cortical Development

Nervous System Malformations

Neurocutaneous Syndromes

Heredodegenerative Disorders, Nervous System

Neurodegenerative Diseases

Genetic Diseases, Inborn

Tuberous Sclerosis Complex

Early Infantile Epileptic Encephalopathy 4

Ann Hallemans, PhD

Patricia Van de Walle, PT, PhD

Anna Jansen, MD, PhD

The aim of this pilot study is to explore whether the knowledge and experience gained during the T-GaiD project (Treatment of Gait Disorders in Dravet Syndrome - NCT03857451) can be transferred to other populations with similar problems, i.e. motor and gait problems as a result of a genetic disorder characterized by epilepsy and developmental delay. In this pilot study, 40 people with Tuberous Sclerosis Complex and 30 people with STXBP1 will be recruited via the Antwerp University Hospital and invited for a gait analysis in the M²OCEAN movement lab. The aim of the pilot study is to evaluate the feasibility of the 3D gait analysis protocol and to determine the sensitivity of the primary (summative measure of the severity of gait abnormalities) and the secondary (spatio-temporal and kinematic gait parameters) outcome measures.

Neurodevelopmental disorders are a group of rare disorders that usually have a genetic cause, each characterized by specific clinical features. Tuberous Sclerosis Complex (TSC or Bourneville's disease), for example, is characterized by the formation of benign tumors, which can develop in almost all organs and tissues. The symptoms vary greatly from person to person, also within one and the same family. Some patients show only limited skin abnormalities, other patients have more affected organs and sometimes become heavily dependent on help. The group of developmental and epileptic encephalopathies (DEE) are genetic neurological disorders that are characterized by epileptic seizures, which usually occur at a (very) young age, and a developmental delay that often leads to an intellectual disability. STXBP1 encephalopathy (STXBP1-E) is an example of an DEE where, in addition to epileptic seizures and developmental delay, motor disorders and gait abnormalities are also frequently seen.

To date, very little is known about motor development in children with TSC and DEE such as STXBP1-RD. Prospective research in the EPISTOP cohort showed that motor development is often delayed in the first years of life, especially in children who also show characteristics of. In clinical practice, we observe progressively increasing gait problems in a number of children that can lead to loss of autonomous steps at a young adult age. A recent study in adult patients with STXBP1-RD showed that about half of the patients were able to walk in adulthood and that those who could walk often had significant gait problems, which appear to be multifactorial in nature.

The ultimate goal of this project is to characterize gait patterns in children, adolescents and young adults with rare genetic disorders, in order to gain new insights into the pathomechanisms of motor and mobility problems. In the long run, these insights will be indispensable for providing an adequate, scientifically substantiated treatment to reduce and, if possible, prevent the gait disorders.

Gait in Rare Diseases

Identification of Gait Disorders in Children, Adolescents and Young Adults With Rare Genetic Diseases

body height will be measured in standing position using a ruler and expressed in centimeters

weight in kilograms will be measured using a calibrated scale

height (in centimeters) and weight (in kilograms) will be combined to determine the body mass index

leg length in centimeters will be measured from the anterior superior iliac spine to the medial malleolus, using a tape measure

Passive joint range of motion (in degrees) will be measured during clinical examination using a goniometer

Skeletal alignment (in degrees) will be measured during clinical examination using a goniometer. Skeletal malformations such as hyperlordosis, kyphosis, bow legs, pes valgus and pes planovalgus will be recorded.

Hamstrings length (popliteal angle in degrees) and iliopsoas length (Thomas test in degrees) will be measured during clinical examination using a goniometer

The Medical Research Council muscle scale is a 6-point scale with minimum score 0 = no muscle contraction and maximum score 5 = normal muscle power.

To obtain a summary index of overall gait pathology, the Gait Profile Score will be calculated based on nine relevant lower limb joint angular time profiles collected during 3D gait analysis. These are anterior pelvic tilt, pelvic list, pelvic rotation, hip flexion and extension, hip ad- and abduction, hip rotation, knee flexion and extension, ankle dorsi- and plantar flexion and the foot progression angle. The gait profile score provides the average root mean squared error of the joint angular time profile with respect to normal walking and is presented in degrees. Higher values indicate a larger deviations from normal gait.

The gait pattern is assessed by instrumented 3D gait analysis using the standardized Vicon Clinical Gait Model. Joint rotation angles of the major joints of the lower limbs will be described during walking.

Functional mobility will be assessed during parent interview using the Functional Mobility Scale (FMS). The FMS is a 6-point scale with maximum score of 6 being the most functional outcome (independent on all surfaces) and minimum score of 1 being the least functional outcome (uses wheelchair)

Mobility limitations during daily activities inside and outside of the house will be assessed during parent interview using the validated Dutch translation of the Mobility Questionnaire 28 (MobQuest28), Dutch version: MobiliteitsVragenlijst 28 (MoVra28). The MobQuest28/MoVra28 consists of 28 items with a 5-point rating scale (0 = without any difficulties to 4 = impossible without help). A total score (0-100) indicates the mobility limitations.

Spots Global Cancer Trial Database for stxbp1 encephalopathy with epilepsy