What are the diagnostic criteria for a mild traumatic brain injury (mTBI), also known as a concussion?

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From the Guidelines

Diagnosing a concussion requires a thorough medical evaluation by a healthcare professional, focusing on symptoms and neurological examination, as outlined in the diagnostic criteria that emphasize at least one of the following signs: alteration of mental state, posttraumatic amnesia, loss of consciousness, or other signs of focal and transient neurologic dysfunction 1. When diagnosing a concussion, healthcare professionals will typically assess the patient's history of the injury, perform a neurological examination, and evaluate symptoms such as headache, dizziness, confusion, memory problems, nausea, sensitivity to light or noise, and balance issues.

  • The diagnosis of a concussion is primarily based on clinical evaluation, including:
    • Detailed history of the injury
    • Neurological examination
    • Assessment of symptoms
  • Standardized assessment tools like the Sport Concussion Assessment Tool (SCAT5) or cognitive testing may be used to evaluate memory, concentration, and reaction time.
  • Imaging tests like CT scans or MRIs might be ordered in some cases to rule out more serious brain injuries, though most concussions don't show up on these scans. It's essential to note that symptoms may not appear immediately after injury and can develop over hours or days, so monitoring for 24-48 hours is crucial even if initial symptoms seem mild, as persistent postconcussion symptoms (PPCS) can occur in a significant proportion of patients, comprising physical, cognitive, and emotional or behavioral symptoms 1.
  • The diagnostic criteria for concussion or mild traumatic brain injury (mTBI) emphasize the importance of identifying at least one of the following signs:
    • Any alteration of mental state immediately after injury
    • Posttraumatic amnesia for less than 24 hours
    • Loss of consciousness for less than 30 minutes
    • Other signs of focal and transient neurologic dysfunction Never attempt to self-diagnose a concussion, as proper medical evaluation is essential for appropriate treatment and recovery guidance, especially considering that up to 34% to 44% of patients with concussion or mTBI experience symptoms at 3 to 6 months after injury, and between 5% and 20% experience symptoms at 12 months after injury 1.

From the Research

Diagnosing a Concussion

To diagnose a concussion, several steps and assessments can be taken, as outlined in various studies 2, 3, 4, 5, 6.

  • Clinical Evaluation: A thorough clinical evaluation is essential, including a detailed history and physical examination 4.
  • Neurological Examination: An elemental neurological examination should be performed, emphasizing the oculomotor/ophthalmologic and vestibular systems 4.
  • Musculoskeletal Assessment: Appropriate musculoskeletal assessment of the craniocervical and upper shoulder girdle complex should be conducted 4.
  • Supplementary Tests: Supplementary tests, such as the Buffalo Concussion Treadmill Test and tests of neurocognitive function, can aid in the differential diagnosis of concussion 4.
  • Physical Examination Toolbox: A practical concussion physical examination toolbox may include evaluation of cranial nerves, manual muscle testing, and deep tendon reflexes; inspecting the head and neck for trauma or tenderness and cervical range of motion; Spurling maneuver; a static or dynamic balance assessment; screening ocular examination; and a mental status examination 5.

Assessment Tools and Management

Various assessment tools and management strategies are available for diagnosing and managing concussion, including:

  • Standardized Clinical Tools: Standardized clinical tools have been developed and validated for assessment of acute concussion across injury settings 2.
  • Consensus Guidelines: Consensus guidelines provide guidance regarding injury management and approaches to ensure safe return to activity after acute concussion 2.
  • Symptomatic Treatment: Symptomatic treatment and return to learn/play recommendations are essential components of concussion management 6.
  • Rapid Removal from Play: Rapid removal from play is crucial in managing concussion, and inappropriate management may lead to recurrent concussions, prolonged recovery, and potential long-term consequences 6.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Diagnosis and Management of Acute Concussion.

Physical medicine and rehabilitation clinics of North America, 2017

Research

Concussion: Evaluation and management.

Cleveland Clinic journal of medicine, 2017

Research

Physician Medical Assessment in a Multidisciplinary Concussion Clinic.

The Journal of head trauma rehabilitation, 2019

Research

Concussion Evaluation and Management.

The Medical clinics of North America, 2019

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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