Complex Regional Pain Syndrome (CRPS), Segmental Exclusion Syndrome, Upper Limb Neglect (Peripheral)
Conditions
Keywords
Peripersonal Space, Virtual Reality, Body Schema, Reachability Judgment
Brief summary
This study aims to evaluate the representation of action peripersonal space (PPS) in subjects suffering from unilateral segmental exclusion syndrome of the upper limb compared to healthy control subjects. Segmental exclusion is defined by non-use or under-use of a limb segment without central nervous system damage. The study hypothesizes that this syndrome leads to a modification (shrinkage) of the PPS representation. Participants will perform reachability judgments in a Virtual Reality (VR) environment.
Detailed description
Segmental exclusion syndrome often occurs after limb trauma and manifests as a neglect-like behavior of peripheral origin, sometimes associated with Complex Regional Pain Syndrome (CRPS). The study explores whether the lack of limb use affects the representation of peripersonal space (PPS)-the space immediately surrounding the body where interactions with objects occur. The study is monocentric, observational, with a matched control group. Participants will undergo: Clinical assessment (questionnaires on pain, anxiety, body perception, and kinesiophobia). A Virtual Reality (VR) test (approx. 40 minutes). In VR, participants will judge whether a cylinder presented at different distances and angles is reachable without moving (Perceived Reachable Distance - DMA-p). This will be compared to their Real Reachable Distance (DMA-r). The goal is to measure the error of judgment to assess PPS representation and check for correlations with body schema disturbances or functional impairment
Interventions
BEHAVIORALReachability Judgment Task in VR.
Participants wear an Oculus Quest 2 VR headset. They first perform a motor task to measure Real Reachable Distance (DMA-r). Then, they perform a perceptual task where they must judge, without moving, if a virtual object is reachable (DMA-p). The test evaluates different spatial planes (front, 45° right, 45° left) and heights (shoulder, navel).
Sponsors
Union de Gestion des Etablissements des Caisses d'Assurance Maladie - Nord Est
Study design
Observational model
CASE_CONTROL
Time perspective
CROSS_SECTIONAL
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
(patients): * Age ≥ 18 years. * Presenting unilateral exclusion symptom of the upper limb or part of the hand evolving for \> 3 months. * No contraindication to force work in daily activities. * For patients with finger exclusion: at least 2 perturbed items related to exclusion on tests 3 and 4 of the "Bilan 400 points". * Affiliated to a social security scheme. * Able to understand simple orders. Inclusion Criteria (Controls): * Age ≥ 18 years. * No history of upper limb impairment with sequelae.
Exclusion criteria
(All): * Visual impairments. * Central neurological pathology. * Unstabilized psychiatric pathology. * Communication or comprehension difficulties. * Under legal protection or unable to consent. * Pregnant or breastfeeding women. * Cervical pathology contraindicating VR headset use. * Epilepsy. * Upper limb pathology unrelated to exclusion. * Inability to stand for 40 minutes.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Judgment Error of Reachability | Day 1 (During the 40-minute VR assessment) | The Judgment Error of Reachability is a single composite metric calculated as: ((DMA-p - DMA-r) / DMA-r) × 100, expressed as a percentage (%). Both DMA-p (Perceived Maximum Reachable Distance) and DMA-r (Real Maximum Reachable Distance) are measured in centimeters, and their ratio yields a single dimensionless percentage score. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Body Perception Disturbance Score | Day 1 (Before VR task) | Assessed using the Bath CRPS Body Perception Disturbance Scale (French version). Scores range from 0 to 57, with higher scores indicating greater disturbance. |
| Functional Impairment Score (400-Point Hand Assessment) | Day 1 | Evaluated using the 400-Point Hand Assessment, which measures functional hand use. The score ranges from 0 to 400, where higher scores indicate better functional performance (better outcome). |
| Anxiety and Depression Score (HAD) | Day 1 | Hospital Anxiety and Depression Scale. Scores range from 0 to 21 for each dimension (Anxiety and Depression). |
| Kinesiophobia Score (Tampa Scale) | Day 1 | Tampa Scale for Kinesiophobia (TSK). Assesses fear of movement. Scores range to 68; \>40 indicates significant kinesiophobia. |
| Pain Catastrophizing Score (PCS) | Day 1 | Pain Catastrophizing Scale. Scores range from 0 to 52. |
Countries
France
Contacts
CONTACTAmélie Touillet, MD
CONTACTJonahtan Pierret, PhD
Outcome results
None listed