We now understand universally that a concussion should be defined as a mild traumatic brain injury. A commonality amongst all concussions, is that the injuries sustained in the brain will include a cascade of metabolic, inflammatory, vascular, and neurologic changes. Often, the similarity can stop there, as each concussion is different in physiology and presentation, even among persons of the same apparent mechanism of injury. Just as we know that when an athlete, student, laborer, or grandmother are concussed, the injuries can differ by more than these effects of age, but by the entire manifestation or presentation altogether.
It is additionally noteworthy that for an injury to be defined as a concussion, it does not need to include either a loss of consciousness or a direct blow to the head. In a motor vehicle or on-field accident involving a whiplash mechanism – without head impact – an individual can have experienced a concussion due to the nature of the acceleration-deceleration of the brain inside the skull. Equally important to clarify is that the severity of a concussion cannot be predicted by medical personnel with onset. Rather, more accurate prognostications regarding recovery timetables require information about symptoms in the first 48 to 72 hours.
The clinical presentation of concussion can be of singular or, most often, of multiple subtype. We can classify concussion by these subtypes, and by severity, according to the length of time that the individual experiences symptoms. The most commonly recognized subtypes include:
- Neck pain
Treatment paradigms are best built around the symptoms, rather than patient age or mechanism of injury. While it would be beyond the scope of this blog to comprehensively address a treatment program for each subtype, a cursory overview follows:
Headache: Best practices include identifying and treating the subtype of headache and root cause: visual, mechanical, or cognitive (overload: stimuli, pressure, etc)
Neck pain: Rehabilitation includes a combination of manual therapy, multidirectional stabilization, and sensory integration of joint position error (movement of the cervical spine coordinating with visual and vestibular stimuli) testing and training.
Cognitive: Multidisciplinary programming that includes the most dispersed (interconnected) cognitive functions of attention, perception, problem-solving, and awareness. Often, select cognitive impairments that are more localized by nature, can be impaired. These select capacities may include word finding and various aspects of memory. Rehabilitation programs for cognitive impairment are built on principles of learning and neuroplasticity, allowing for a personalized experience of errors, complexity, and salience in treatment.
Dizziness: Vestibular rehabilitation principles are applicable for persons experiencing dizziness after concussion. Specifically introducing a measured-degree of movements and activities that provoke symptoms and stimulate neural recovery through habituation and accommodation – respectively improving tolerance through exposure and recalibrating sensory signals.
Imbalance: Related to principles described in dizziness, rehabilitation for imbalance after concussion includes a systematic introduction of environments, movements, and conditions that provoke imbalance. The exposure being strategized based on person-specific (sport, work, life, etc) interests that cause the recovering brain to reconnect and re-establish accurate and timely voluntary (planned movements) and reactive balance equations.
Visual: Vision rehabilitation after concussion can be extensive and seemingly complex. Visual impairments after concussion most often include central impairments (synthesis of information: perception, movement, distance). Another common impairment includes coordination of the oculomotor system for binocular vision. Additionally, rehabilitation must address coordination of the vestibular and visual systems after concussion – re-establishing formerly reflexive interactions such as the vestibulo-ocular reflex (VOR). Often unrecognized after concussion is peripheral nerve injury to a cranial nerve responsible for eye movement (Trochlear nerve being the most common due to its location).
Formal concussion rehabilitation is most often introduced 48 hours or more after injury. The initial 48 hours can and should include rest, hydration, nutrition, and light exercise – the latter being a novel introduction to early management from world consensus statements based on recent evidence. The subsequent stages of concussion rehabilitation are introduced as symptoms resolve and tolerance increases. These stages include progressive introductions of endurance, stimuli (visual, auditory, cognitive, psychological) and real-life elements for the concussed individual (academic, sport, vocational, etc).
Individuals having concussion symptoms more than 1 month after injury can be said to be experiencing post concussion syndrome (PCS), which speaks to the chronic nature of the symptoms and ultimately the timing of resolution.
Takeaway concepts from this blog include:
- People are individuals with different abilities, goals, personalities and responsibilities prior to a concussion. Their rehabilitation should be similarly individualized and tailored in content and intensity.
- Concussion rehabilitation is a field of emerging science. World consensus statements are helpful in synthesizing the true evidence for our efforts to outline, time, and stage rehabilitation.
- Presentation after concussion cannot be predicted by age, immediate symptoms, or any physical descriptions of the trauma (direction, impact, speed).
- Just like other injuries, rehabilitation of concussion is designed based on the findings of the examination – subjective reporting of symptoms being perhaps the most significant driver. Patients may present with one or more of the six concussion presentations as described. Rehabilitation programs should follow the subtype therein.