This study evaluates the effect of photobiomodulation (PBM) therapy using a MLS® class IV laser on chronic pain and fatigue in patients with hypermobile Ehlers-Danlos Syndrome (hEDS). hEDS is a hereditary connective tissue disorder characterized by joint hypermobility, chronic pain, and debilitating fatigue, for which therapeutic options remain limited.

Participants will receive 10 PBM sessions over 5 weeks (2 sessions per week), using red and near-infrared light (808 nm continuous + 905 nm pulsed) applied to painful areas identified at baseline. Pain (Visual Analogue Scale), multidimensional fatigue (MFI-20), and quality of life (EQ-5D-5L) will be assessed at baseline (T0), end of treatment (week 5), and follow-up (week 10).

This is a pilot observational study - the first to document the effect of MLS® laser PBM in hEDS. No additional procedures beyond routine care are required.

Background: Hypermobile Ehlers-Danlos Syndrome (hEDS) is the most common form of EDS (80-90% of cases), diagnosed according to the 2017 International Consortium criteria. Chronic pain and fatigue are the two most disabling symptoms. No randomized controlled trial has evaluated the effect of MLS® class IV laser photobiomodulation in hEDS to date.

Intervention: Photobiomodulation using ASAlaser M-Hi device (MLS® technology: synchronized 808nm continuous + 905nm pulsed emissions, CE MDR class IV). Progressive fluence: 4 J/cm² (sessions 1-2), 6 J/cm² (sessions 3-6), 8 J/cm² (sessions 7-10). Maximum 3-4 zones per session. Treatment areas individualized based on pain mapping at baseline.

Design: Single-center prospective observational pilot study in private practice. No randomization, no control group, no modification of ongoing treatment.

Statistical analysis: Wilcoxon signed-rank tests (paired, non-parametric), descriptive statistics. Exploratory pilot - no formal power calculation. Target sample size: 20-25 patients.

Inclusion Criteria:

• Age ≥ 18 years
• Confirmed diagnosis of hypermobile Ehlers-Danlos Syndrome (hEDS) according to 2017 International Consortium criteria
• Chronic pain ≥ 3 months, average VAS score ≥ 4/10 over the preceding week
• Stable analgesic treatment for ≥ 4 weeks (if any)
• Follow-up at Centre Médical ISM, Boulogne-Billancourt
• Informed and non-opposition signed

Exclusion Criteria:

• Suspicious or malignant skin lesion on areas to be treated
• Non-modifiable photosensitizing treatment
• Pregnancy or breastfeeding
• Photosensitive epilepsy
• Acute articular inflammatory flare at inclusion date
• Analgesic treatment modification within 4 weeks prior to inclusion
• Simultaneous participation in another research protocol

Adult patients with confirmed hypermobile Ehlers-Danlos Syndrome (hEDS), diagnosed according to the 2017 International Consortium criteria, presenting with chronic pain (≥ 3 months, VAS ≥ 4/10) and/or fatigue, followed in private outpatient practice at Centre Médical ISM, Boulogne-Billancourt, France. Patients are recruited consecutively among those already receiving photobiomodulation therapy as part of their routine care. No healthy volunteers are included.