Piezo2-related Arthrogryposis & physiopathOLOgy 3

Study type: Observational, non-interventional, single-center, descriptive study. Goal of the study: The goal of this observational study is to characterize the intensity, variability, and qualitative features of pain in patients with arthrogryposis multiplex congenita (AMC) caused by a gain-of-function mutation in PIEZO2. This population is rare and identified through the French national PARART registry (Pediatric and Adult Registry for patients with ARThrogryposis). Population: Participants are ≥10 years old, have a genetically confirmed gain-of-function PIEZO2 variant, and are registered in PARART. All procedures are conducted remotely; no onsite visit is required. Main questions the study aims to answer: * What is the intensity and day-to-day variability of pain over 14 consecutive days, measured with a Numerical Rating Scale (0-100)? * What are the sensory qualities and anatomical distribution of pain in this population? * How does this pain affect quality of life? * What treatments (pharmacological or non-pharmacological) have been used, and how effective are they? Study design: There is no comparison group. The study is descriptive and aims to characterize the pain phenotype linked to PIEZO2 gain-of-function mutations. What participants will do: Participants will complete the following tasks remotely: At Day 1: Questionnaires: * Saint-Antoine Pain Questionnaire (QDSA) * SF-12 * EQ-5D-5L * Pain monitoring: treatments used For 14 consecutive days (Day 1 to Day 14), on a paper logbook: * Daily self-reported Numerical Rating Scale (NRS, 0-100) for pain * Daily body chart to document pain distribution All data are collected through REDCap and a paper logbook. No clinical exam, biological sampling, or hospital visit is required. The study duration for each participant is 14 days.

NCT Number	NCT07360574
Lead Sponsor	University Hospital, Grenoble
Conditions	Arthrogryposis Multiplex Congenita, Piezo2 Mutation Gain of Function
Enrollment	12 participants
Start Date	2026-02-01
Primary Completion	2026-07 (estimated)
Study Completion	2026-07 (estimated)
Updated on ClinicalTrials.gov	2026-01-22