Post-Concussion Balance Disturbances
Concussion is a major cause of death and disability in the United States, and people of all ages and backgrounds are affected. Moreover, the annual number of concussion-related emergency department visits, hospitalizations, and deaths has been increasing over the past decade. For these reasons, it is important to stay updated with post-concussion–related consequences, such as balance disturbances and vertigo.
At the American Academy of Neurology’s Sports Concussion Conference, Jamie M. Bogle, AuD, PhD, spoke about these consequences and what it means for the public health of the United States.1 Dr Bogle is the division chair of Audiology at Mayo Clinic AZ and is an assistant professor of audiology at the Mayo School of Medicine in Scottsdale, Arizona.
Here are Dr Bogle’s responses to our burning questions.
NEUROLOGY CONSULTANT: What kind of balance disturbances are common after a concussion?
Jamie Bogle: Dizziness and imbalance are common symptoms after concussion and are important to address early in the intervention process. Patients with initial dizziness are likely to experience prolonged recovery along with increased times for return to school and return to play. Additionally, dizziness is quite common in those with persistent post-concussion symptoms and often requires multidisciplinary management. Most providers find dizziness to be a challenging symptom to manage, especially if there is not a clear etiology. My session aimed to provide some guidance on post-concussion dizziness and how to best manage it.
NEURO CON: Is vertigo treated any differently in patients with a history of concussion? If so, how and why?
JB: There are likely numerous underlying mechanisms associated with post-concussion dizziness. Patients describe various types of dizziness, including vertigo, lightheadedness, unsteadiness, and motion sensitivity. Post-concussion, patients may present with peripheral or central vestibular dysfunction, both, or neither. Sorting out the source of a patient’s dizziness and imbalance is the first step—this will help guide your recommendations.
Common concerns for dizziness post-concussion include positional vertigo (benign paroxysmal positional vertigo), migraine, and autonomic dysfunction. Each of these concerns requires specific rehabilitation and management options that will unfortunately not be of much help to the other conditions.
In the general population, the most common peripheral vestibular problem is benign paroxysmal positional vertigo (BPPV). BPPV occurs when otoconia become dislodged from the otolith organs and migrate into a semicircular canal. Patients with BPPV experience significant rotational vertigo with position changes such as rolling over in bed, tipping the head back, or bending over. This type of vertigo is short lived but may recur with additional changes in position.
BPPV is diagnosed using the Dix-Hallpike maneuver and looking for fatigable torsional nystagmus. For patients with positive findings, repositioning maneuvers allow for the relocation of otoconia and resolution of vertigo. Once BPPV has been identified, treatment can be quite successful and can reduce symptoms quickly.
Fortunately, permanent peripheral vestibular dysfunction is uncommon post-concussion. For patients negative for positional vertigo, the most likely source of dizziness is associated with the central vestibular system, such as in migraine and autonomic disorders. These disorders often demonstrate normal findings for dizziness-specific testing focused on the peripheral system. Dizziness and imbalance are common in individuals with migraine disorders with or without concussion. Symptoms such as vertigo, floating sensation, and significant motion sensitivity are often reported. Appropriate headache management with additional vestibular rehabilitation are needed to successfully reduce this type of dizziness.
Autonomic disorders may also present post-concussion. Dizziness associated with autonomic disorders is typically described as postural lightheadedness but may also include other types of dizziness. When a patient presents with dizziness symptoms following orthostatic challenge, consider follow-up with an autonomic disorders specialist. It is especially important for these patients to initiate an exercise protocol as soon as possible to avoid deconditioning. Migraine and autonomic disorders are common post-concussion and are likely associated with a significant proportion of the dizziness experienced by our patients.
NEURO CON: What else should neurologists know about balance disturbances and vertigo as clinical consequences of concussion?
JB: Sensory integration is the most important concept to understand for the management of patients with dizziness post-concussion, regardless of the underlying cause. The vestibular and balance system requires dynamic flexibility and precise timing of neural transmission from multiple systems. This can be evaluated clinically by testing dynamic balance function and gaze stability—simple test methods that evaluate how well multiple sensory systems are integrating to complete a specific task. When this integration is abnormal, as is possible post-concussion, sensory information is misinterpreted. Often this leads to reduced balance and overdependence on visual information. The patient may report increased symptoms associated with movement illusions, instability, blurry vision, and motion sensitivity. These symptoms are typically triggered by quick head or body movements, busy visual environments, or complex visual tasks. Vestibular rehabilitation is the most important component to include when working with a post-concussion patient presenting with abnormal sensory integration.
NEURO CON: What is your overall key take-home message for neurologists?
JB: The vestibular system is complex and often requires a multidisciplinary team. There may be various factors contributing to a patient’s dizziness and imbalance symptoms, and patients will present with several possibilities. There is not one specific method for treating dizziness in a patient post-concussion, but management is incredibly important. Attention to dizziness and balance concerns post-concussion will allow individuals to return to work, school, and play more efficiently, reducing the symptom burden on the patient and improving tolerance to rehabilitation as well as reducing the burden on health care resources.
Reference:
- Bogle JM. Clinical consequences of concussion part ii: balance disturbances and vertigo. Talk presented at: American Academy of Neurology’s Sports Concussion Conference; July 26-28, 2019: Indianapolis, IN. https://www.aan.com/conferences-community/regional-conferences/sports-concussion/browse-programs/#subnav. Accessed July 3, 2019.