Neurovascular Examination of an Injured Finger in Pediatric Patients
A focused neurovascular examination of an injured pediatric finger must systematically assess vascular perfusion, sensory nerve function, and motor nerve function, with the Ten Test being the preferred sensory evaluation method over traditional two-point discrimination.
Systematic Examination Approach
Vascular Assessment
Evaluate digital perfusion immediately:
- Capillary refill: Press the fingertip and observe return of color (normal <2 seconds)
- Color and temperature: Compare to uninjured digits for pallor, cyanosis, or coolness
- Pulse assessment: Palpate radial and ulnar pulses at the wrist level
- Critical circulatory issues require immediate identification as they dictate urgent surgical intervention 1
Important caveat: Visual assessment alone (even with photographs) has only 48% sensitivity for detecting critical circulatory problems, so direct clinical examination is essential 2.
Sensory Nerve Evaluation
Use the Ten Test rather than two-point discrimination 3:
- Apply light touch to the radial and ulnar aspects of each finger
- Ask the child to identify which side is being touched
- The Ten Test is more reliable, reproducible, and practical in the emergency setting compared to two-point discrimination, which has limited reproducibility 3
- Test both digital nerves (radial and ulnar) on each injured finger
For younger children who cannot cooperate with formal testing:
- Observe withdrawal response to gentle touch
- Note any asymmetry in response compared to uninjured digits
Motor Function Assessment
Evaluate tendon integrity systematically 1, 4:
Flexor tendons:
- Flexor digitorum profundus (FDP): Stabilize the middle phalanx and ask child to flex the distal interphalangeal (DIP) joint
- Flexor digitorum superficialis (FDS): Hold other fingers in extension and ask child to flex the proximal interphalangeal (PIP) joint
Extensor tendons:
- Test extension at each joint level (DIP, PIP, metacarpophalangeal)
- Assess for "mallet finger" deformity (inability to extend DIP joint)
Additional Critical Assessments
- Rotational alignment: Have child make a gentle fist—all fingers should point toward the scaphoid tubercle 4
- Deviation: Observe for angular deformity at rest and with gentle motion
- Open wounds: Any laceration requires assessment for underlying nerve, artery, and tendon injury, as "innocent-looking wounds from glass lacerations may disguise extensive damage" 5
Key Clinical Pitfalls
Examination challenges in children: Pediatric patients may be uncooperative due to pain or anxiety, making examination difficult 1. Consider:
- Adequate analgesia before examination
- Parental presence for comfort
- Age-appropriate communication
High-risk injuries requiring hand surgery consultation 1:
- Any laceration with suspected neurovascular or tendon injury
- Amputations at any level
- Fingertip injuries with bone exposure or significant tissue loss
Documentation: Record specific findings for each component (vascular, sensory radial/ulnar, motor FDP/FDS/extensor) rather than generic statements, as this guides surgical decision-making and medicolegal documentation.
The examination must be thorough despite pediatric challenges, as missed neurovascular injuries can lead to permanent functional impairment and significant morbidity 4, 5.