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

N/AEnrolling By InvitationNCT07432685

Charitable Organisation Charitable Fund Superhumans (Co Cf Superhumans)100 enrolled

Overview

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.

Study Type

OBSERVATIONAL

Enrollment

100

Conditions

Residual Limb Pain Post-Traumatic Limb Pain Extremity Trauma Combat-Related Limb Injury

Eligibility

Sex: ALLMin age: 18 YearsMax age: 50 Years

Medical Language ↔ Plain English

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

Outcomes

Primary Outcomes

Chronic limb pain at 3 months

Presence of chronic limb pain at 3 months following injury Chronic limb pain is defined as persistent or recurrent pain localized to the anatomically injured limb, with an average Numeric Rating Scale (NRS) score ≥3 (0-10 scale) during the preceding 7 days at the 3-month follow-up. Pain intensity will be assessed using a standardized 11-point Numeric Rating Scale (0 = no pain; 10 = worst imaginable pain). Participants will be categorized as: Yes - chronic limb pain present (NRS ≥3) No - chronic limb pain absent (NRS \<3) The primary analysis will evaluate the association between baseline injury kinematics variables (energy class, dominant force direction, dominant force component, and kinematics severity grade K0-K3) and the presence of chronic limb pain at 3 months.

Time frame: Assessed at 3 months (90 days ± 14 days) after injury Pain assessment will be conducted during the scheduled 3-month follow-up visit (between Day 76 and Day 104 post-injury).

Secondary Outcomes

Chronic limb pain at 6 months

2\. Chronic Limb Pain at 6 Months Secondary Outcome Measure: Presence of chronic limb pain at 6 months following injury Description: Persistent or recurrent limb pain defined as an average Numeric Rating Scale (NRS) score ≥3 (0-10 scale) during the preceding 7 days at the 6-month follow-up visit. Participants will be categorized as: Yes - chronic limb pain present (NRS ≥3) No - chronic limb pain absent (NRS \<3)

Time frame: 6 months (180 ± 21 days) after injury

Pain Intensity Over Time (Continuous NRS Score)

Secondary Outcome Measure: Pain intensity measured using the Numeric Rating Scale (0-10) Description: Pain intensity assessed using a standardized 11-point Numeric Rating Scale (0 = no pain; 10 = worst imaginable pain). The mean NRS score at each follow-up visit will be analyzed as a continuous variable.

Time frame: Baseline (within 72 hours of injury), 6 weeks (±7 days), 3 months (90 ± 14 days), and 6 months (180 ± 21 days) after injury

Pain extent measured as percentage of affected limb surface area

Pain distribution recorded using standardized digital limb body maps. Pain extent will be quantified using digital planimetry and expressed as percentage (%) of total limb surface area.

Time frame: 6 weeks (±7 days), 3 months (90 ± 14 days), and 6 months (180 ± 21 days) after injury