Kinematics-Based Prediction of Chronic Pain After Combat-Related Extremity Trauma

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.

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