Combat-related extremity trauma frequently results in persistent pain, including neuropathic, residual limb, and phantom limb pain. The kinematics of injury-including energy level, direction of force, and dominant force components-may independently predict tissue deformation, nerve stress, and the transition from acute to chronic- pain. This prospective observational cohort study will assess whether kinematics-only variables predict chronic pain outcomes after combat-related upper and lower limb injuries. Pain outcomes will include pain intensity, pain extent (surface/area), neuropathic pain features, and mechanical pain sensitivity measured using von Frey filaments.

Adults with combat-related limb trauma will be enrolled within 72 hours of injury. Baseline assessment will include a standardized kinematics classification documenting (1) energy class, (2) dominant direction of force, (3) dominant force component, and (4) kinematics severity grade (K0-K3). Participants will be followed at 6 weeks, 3 months, and 6 months. The primary endpoint is chronic limb pain at 3 months. Secondary endpoints include chronic pain at 6 months, pain area, neuropathic features, and mechanical pain thresholds using von Frey testing at standardized limb sites (injured and contralateral control). This is a non-interventional study; no treatment decisions are dictated by the protocol.

Inclusion Criteria:

• Age ≥18 years
• Combat-related extremity trauma involving upper and/or lower limbs
• Blunt limb trauma
• Penetrating limb injury (ballistic or shrapnel)
• Blast-related limb injury
• Hybrid injury (blast plus fragment)
• тTraumatic amputation (partial or complete)
• Baseline assessment performed within 72 hours of injury
• Acute limb pain with Numeric Rating Scale (NRS) score ≥3 at baseline
• Ability to provide informed consent
• Ability to participate in follow-up assessments

Exclusion Criteria:

• Inability to complete follow-up assessments
• Severe cognitive impairment preventing informed consent
• Declines participation

This study includes adults with acute combat-related extremity trauma presenting to participating trauma and rehabilitation centers in Ukraine.

Eligible participants have upper and/or lower limb injuries resulting from combat-related mechanisms, including blunt trauma, penetrating (ballistic or shrapnel) injuries, blast-related injuries, hybrid (blast plus fragment) injuries, and traumatic amputations (partial or complete).

Participants must be enrolled within 72 hours of injury and report acute limb pain with a Numeric Rating Scale (NRS) score ≥3 at baseline.

The study population represents a real-world cohort of combat-injured adults at risk for persistent limb pain, neuropathic pain, residual limb pain, and phantom limb pain.

De-identified individual participant data underlying the published results will be made available to qualified researchers upon reasonable request. Data will include baseline kinematics variables, pain measures (NRS), pain extent, DN4 scores, and mechanical pain thresholds (von Frey), including amputation subgroup outcomes where applicable.

Data will be shared after approval of a research proposal and execution of a data use agreement. No identifiable information will be disclosed. Data will be available beginning 6 months after publication of the primary results.

Beginning 6 months after publication of the primary results and available for 5 years thereafter.

De-identified data will be available to qualified researchers upon approval of a research proposal and signing of a data use agreement. Data will be shared securely; no identifiable information will be provided.