Arthrogryposis Multiplex Congenita in Pediatric Age: Correlation Between MUScular MRI and Functional Evaluation
Condition: Arthrogryposis Multiplex Congenita; AMC-Arthrogryposis Multiplex Congenita; Pediatric ALL
MeSH terms: Arthrogryposis
Study type: Observational

Summary: 
      The aim of our study is to evaluate the correlation between quantified fibro-adipous
      infiltration of muscles on MRI assessed by MERCURI Score and the functional abilities
      (deficiencies, activity limitations and social participation of pediatric patients with
      arthrogryposis.
    

Detailed description: 
      Arthrogryposis multiplex congenita (AMC) is a group of rare diseases characterized by joint
      contractures at two or more distinct joint levels at birth. More than 400 causes are
      currently known. The prevalence is estimated at 1/3000 to 1/2000. Joint limitations are not
      progressive, but the functional consequences have a lifelong impact on patients.

      Correlations between fibro-adipous infiltration and muscular deficits have already been
      studied in other neuromuscular diseases such as Pompe disease or Duchenne muscular dystrophy.
      These studies concluded on a good correlation between disease progression and severity,
      muscle strength, and fatty infiltration assessed by Mercuri score. The investigators
      concluded that muscular MRI can be used as a non-invasive biomarker and a tool to follow the
      progression of neuromuscular disease and help evaluate the potential effects of therapies.

      The aim of this project is to define whether MRI could also be used as a tool, through the
      assessment of muscle fatty infiltration, to help predict the functional abilities of our
      patients with AMC, and more specifically the two most frequent types, Amyoplasia and distal
      arthrogryposis.

      The investigators will analyze fatty infiltration measured by muscle MRI and quantify it
      using the MERCURI score which was developed by Mercuri et al. (Mercuri et al. 2002) as a
      semi-quantitative score to quantify fibro-adipose muscle infiltration on muscle MRI.

      The investigators will evaluate musculoskeletal deficiencies and limitations of activity from
      data obtained from patients followed in our AMC reference center at the University Hospital
      Grenoble Alpes (CHUGA).

      The investigators will include data from 220 children, 97 of whom have had a complete
      check-up including a muscle MRI. The investigators will study the existence of a correlation
      between this score and the deficiencies and limitations of activity.

      The investigators will then evaluate the potential predictive role of fatty infiltration
      measured on MRI in the functional abilities of the patients.

      This characterization will help to better determine and anticipate the functional capacities
      of our patients from the beginning of their treatment to improve their functional prognosis.

      This initial work could enhance the reflection on the biomechanical modeling of joints and
      key functions such as standing and the acquisition of walking, in order to pave the way for
      rehabilitation and compensation methods that are better adapted to patient's needs.
    

Intervention name(s): No intervention
Intervention type(s): Other
Intervention description(s): No intervention
Observational model: Cohort
Time perspective: Retrospective
Sampling method: Non-Probability Sample
Study population: 
        Pediatric patient from PARART registry (Paediatric and Adult Registry on ARThrogryposis)
        evaluated in the reference center (RC) for Arthrogryposis Multiplex Congenita from 2010
        until 2021). All patients were evaluated by a geneticist, and had a complete check up in
        the pediatric PMR unit (physical medicine and rehabilitation physician, physiotherapists,
        occupational and speech therapists) and had imaging analysis by whole body muscular MRI.
      
Keywords: Arthrogryposis Multiplex Congenita; Pediatric; Mercuri Score; MRI; Fibro-adipous infiltration; Functional capacity; Rehabilitation; Retrospective observational study