Concussion Neurological Exam
A full neurological exam includes not only the classic tests to determine whether the nervous system is working properly, but also a rudimentary assessment of cognitive function. Most important, it is supposed to contain a clinical interview (including Rivermead and CDC ACE among others). The clinical interview is only of value, however, when the diagnosis is not presumed at the beginning.
Far too often in concussion cases, the exam is limited to a quick check for focal neurological deficits. The quick step exam will rarely identify the type of deficits typically associated with a mild brain injury. The physical aspect of the exam should be a diligent, and detailed evaluation. A diligent doctor/neurologist may uncover focal deficits, which were missed at the time of the injury. Sadly, the one focal deficit which is most likely to be effected by a concussion, the sense of smell, is the one which is least often checked.
The areas of the physical exam which are most sensitive to post-concussional changes include examination of the IV, V and VIII nerves, those which to some degree involve the eyes. Before a physician concludes that a neurological exam is “normal” Cranial Nerve I, the Olfactory Nerve, must be tested. Damage to sense of smell (and related problems with taste) are very associated common symptoms of brain injury. Such deficits also correlate to disturbing executive function problems in associated geographic areas of the brain, the orbital frontal area. For example, direct damage to cranial nerve II (optic nerve) is rare but impact of the occipital lobe, where the visual cortex lies is not only common but almost expected to cause visual disturbances.
Significant research points to these orbital frontal problems being central to unsuccessful reintegration of the brain injured person into the outside world. Such problems have a remarkable correlation to serious employability concerns.
The Cranial Nerves:
- I. Olfactory – Smell. Very important to carefully evaluate.
- II. Optic – Vision.
- III. Oculomotor – Eye movement.
- IV. Trochlear – Eye movement.
- V. Trigeminal – Controls the muscle and senses of the face.
- VI. Abducens – Eye movement.
- VII. Facial – Taste, expression and facial and scalp movements.
- VIII. Vestibulolocochlear – Hearing and vestibular system.
- IX. Glassopharyngeal – Gag reflex, taste, throat and sinus reflex.
- X. Vagus – throat, voice, gag reflex, coughing, dilations of the stomach.
- XI. Accessory – rotate head, shrug shoulder, raising chin.
- XII. Hypoglossal – muscles of the tongue.