Ultrasound Predictors of Persistent Burn Scar Pain After Blast and Drone-Related Injuries: A Prospective Cohort Study

Participants with burn scars 2-12 weeks after injury will undergo standardized baseline assessment including pain ratings at rest, during movement, and on light touch, DN4 screening, basic scar assessment, and a structured ultrasound examination using a high-frequency linear probe (10-18 MHz). Ultrasound endpoints include scar thickness, echogenicity pattern, Power Doppler vascularity grade, dynamic adhesion score, and nerve involvement defined as presence of ≥2 out of 5 ultrasound criteria (focal nerve thickening, hypoechoic fascicular distortion, nerve traversing scar tissue, reduced gliding, and sonopalpation pain reproduction). Follow-up assessments will be performed at 6 weeks, 3 months, and 6 months. The primary analysis will evaluate the association between baseline ultrasound features and persistent clinically significant scar pain (NRS ≥4 during movement or touch) at 3 or 6 months.

Inclusion criteria

• Age ≥18 years
• Burn injury with clinically formed scar
• Enrollment 2-12 weeks after injury
• Scar located on extremities, chest wall, or neck
• Ability to provide written informed consent

Exclusion criteria

• Severe cognitive impairment preventing valid questionnaires
• Hemodynamic instability or inability to complete baseline evaluation
• Active systemic infection (enrollment deferred until stable)
• Pre-existing chronic pain condition unrelated to burn scar that would confound outcomes (investigator judgment)