The United States military uses a standardized assessment tool to quickly evaluate for possible concussion. For any service member who is exposed to an explosion, a training accident or any other blow to the head, a key first step is to administer the Military Acute Concussion Evaluation 2, known as MACE 2. 

The MACE 2 is outlined on a portable pocket card to identify symptoms of a mild traumatic brain injury at the point of care. TBI symptoms can include headache, dizziness, and problems with sleep, vision or balance. 

“MACE 2 provides a common language and baseline criteria,” Stephanie Maxfield Panker, chief, research support cell with the Traumatic Brain Injury Center of Excellence said. 

TBI Testing: What is MACE 2? 

The military medical community began using MACE in 2006. An updated, six-part MACE 2, was developed in 2018 by adding relevant history questions and a screening for visual and dizziness related symptoms.  

“The changes improved the standard of care for patients by reducing the risks of overlooking patients with those problems,” Gary McKinney, a certified brain injury specialist and TBICoE chief of clinical practice and clinical recommendations, said. 

The MACE 2 provides detailed concussion screening, a cognitive test, a neurological exam, symptom specific questions and screening, and a history section on concussion.  

How Does the MACE 2 Evaluation Work? 

The MACE 2 assessment starts with monitoring for key or urgent signs of concern: 

• worsening level of consciousness 
• double vision or loss of vison 
• restlessness, combative or agitated behavior 
• repeated vomiting
• seizures 
• weakness or tingling in the arms or legs 
• severe or worsening headache 

If the assessment identifies any of those red flags, the patient requires an immediate referral to a higher level of care. In a combat zone, that might warrant an urgent medical evacuation, McKinney said. 

If there are no red flags, the provider will ask questions about the event that caused the injury to determine if the patient has a changed level of consciousness or memory problems. The provider also asks for some medical history, such as whether the patient has had a concussion before, when, and how severe it was. 

The evaluator also conducts an initial mental function exam. For example, the provider might ask whether the patient knows where they are and can remember what happened right before the injury. 

A nervous system function exam is next. The evaluator will test a patient’s ability to speak coherently and to walk correctly. That’s followed by a test of the patient’s ability to concentrate and recall memories. Asking the patient to follow the evaluator’s finger movements can check for dizziness or eyesight problems. 

The initial MACE 2 score provides an assessment at that particular time. Future MACE 2 scores may help the provider understand how the patient’s symptoms are changing to determine if the patient’s mental status has improved or worsened over time. 

Concussion Testing on the Front Lines 

The joint services’ Medical Education and Training Campus at Joint Base San Antonio-Fort Sam Houston, Texas, trains combat medics, along with combat life savers, to recognize potential head injuries along with the signs and symptoms that would require a MACE 2 and further evaluation. 

“Combat medics are instrumental in identifying the possibility of a TBI based on mechanism of injury, signs and symptoms, assessing for severity, and administering the MACE 2 as soon as possible after evacuation from the point of injury,” Jeremy Clarno, METC’s Combat Medic Specialist Training Program field craft chief, said. “This is crucial because early detection and treatment are the keys to preventing long-term effects.” 

Evaluators typically perform MACE 2 evaluations at battalion-level aid stations or higher.