What is the proper technique for manual in-line stabilization (MILS) in a patient with suspected spinal trauma?

Manual In-Line Stabilization Technique for Suspected Spinal Trauma

Manual in-line stabilization (MILS) should be performed by trained providers to minimize cervical spine movement in patients with suspected spinal trauma, though there is insufficient evidence regarding its effectiveness in preventing secondary neurological injury. 1

Proper MILS Technique

Positioning

• Position yourself at the head of the patient
• Ensure the patient is supine on a firm surface
• Place your hands on both sides of the patient's head:
  • Palms against the lateral aspects of the head
  • Fingers supporting the occiput
  • Thumbs positioned anterior to the ears

Execution

• Apply gentle but firm pressure to maintain the head and neck in a neutral position
• Avoid excessive traction or compression
• Maintain alignment with the thoracic spine and pelvis
• Continue stabilization until definitive immobilization is achieved

Key Principles

• Maintain neutral alignment - avoid flexion, extension, rotation, or lateral bending
• Do not release the hold until proper immobilization devices are secured
• Communicate with other providers during the procedure

Evidence and Limitations

The 2020 International Consensus on First Aid Science notes there is insufficient evidence for or against manual cervical spine stabilization 1. This recommendation remains unchanged since 2010, highlighting the limited research in this area.

Manual stabilization techniques require education, training, and practice to perform correctly 1. While first aid guidelines in several countries (Japan, Australia, New Zealand, UK) recommend manual support of the head for adults with suspected cervical spine injury, the techniques are likely beyond the scope of basic first aid providers 1.

Research shows that MILS may have important limitations:

• MILS can degrade laryngoscopic view during intubation attempts, potentially causing hypoxia 2
• During airway management, MILS may increase pressure applied by the laryngoscope blade (717±339 mmHg vs. 363±121 mmHg without MILS), which could potentially increase pathologic cervical motion 3
• Studies comparing manual versus mechanical turning methods found manual techniques produced 2-3 times more cervical spine angular motion than using specialized equipment like Jackson tables 4

Special Considerations

During Airway Management

• MILS is standard care for acute trauma patients with suspected cervical spine injury during airway management 2
• Consider alternative intubation techniques when difficult visualization is encountered:
  • Video laryngoscopes
  • Optical stylets
  • Supraglottic airways 2

During Collar Application/Removal

• Motion occurs in all planes during collar application/removal (maximum 3.4° angulation and 4.4mm displacement) 5
• One-piece collars may produce less motion in flexion/extension during application compared to two-piece collars (1.8° vs 2.6°) 5
• Only trained practitioners should apply/remove collars while maintaining MILS 5

Multidisciplinary Approach

• Early spine immobilization is strongly recommended for any trauma patient with suspected spinal cord injury 6
• Transfer to a Level 1 trauma center is associated with improved neurological outcomes 6
• Involve a multidisciplinary team including neurosurgeons, orthopedic surgeons, and rehabilitation specialists 6

Common Pitfalls to Avoid

• Excessive force: Applying too much force can cause discomfort and potentially worsen injuries
• Releasing stabilization prematurely: Maintain MILS until proper immobilization is achieved
• Improper hand positioning: Incorrect hand placement may allow unwanted movement
• Distraction: Maintain focus on stabilization throughout the entire process
• Inadequate communication: Clearly communicate with team members during transfers and procedures
• Prolonged immobilization: Extended periods of immobilization may lead to pressure injuries

MILS remains a standard practice despite limited evidence of its effectiveness in preventing secondary neurological injury. The technique requires proper training and should be performed carefully to minimize movement while awaiting definitive care.