Peripersonal Space Representation in Upper Limb Segmental Exclusion

Union de Gestion des Etablissements des Caisses d'Assurance Maladie - Nord Est

Status: Not yet enrolling

Conditions: Complex Regional Pain Syndrome (CRPS); Segmental Exclusion Syndrome; Upper Limb Neglect (Peripheral)

Treatments: Behavioral: Reachability Judgment Task in VR.

Study type: Observational

Funder types: Other

Identifiers

NCT07349173

2025-A02189-40 (Other Identifier)

IRR-CLP-2023-3

Details and patient eligibility

About

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.

Full 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

Enrollment: 60 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion and exclusion criteria

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.

Trial design

60 participants in 2 patient groups

Patients with Exclusion

Description:

Patients presenting with unilateral segmental exclusion of the upper limb or part of the hand evolving for more than 3 months.

Treatment:

Behavioral: Reachability Judgment Task in VR.

Healthy Controls

Description:

symptomatic volunteers with no history of upper limb impairment with sequelae.

Treatment:

Behavioral: Reachability Judgment Task in VR.