Can a structural leg length discrepancy contribute to persistent concussion symptoms? A case report

In the past several years, concussions and post-concussion syndrome (PCS) have become more commonly recognized conditions. However, with limited physiological explanation for post-concussion syndrome, there is also limited evidence supporting effective treatment. The vestibular system plays a role in postural reflexes and coordinated eye and cervical spine movements and is often disrupted in patients with prolonged concussion symptoms. This disruption has contributed to some of the most debilitating symptoms in PCS patients including dizziness, nausea, and balance deficits. Ongoing, post-concussion, vestibulo-ocular/cervical-ocular disruption due to an underlying structural leg length discrepancy as a contributing factor has not been previously described in the literature. A case of PCS with initial conservative treatment of their structural leg length discrepancy and subsequent vestibulo-ocular/cervical-ocular rehabilitation is presented.

Design and Development of a Rotating Chair to Measure the Cervico-Ocular Reflex

Eye reflexes that stabilize gaze are essential in navigating daily life. One such reflex is the cervico-ocular reflex (COR). An important neural structure involved in the COR is the cerebellum, which facilitates proper gaze stability through sensorimotor integration to adjust eye movements accordingly. This reflex is tested by fixating the head in space and rotating the body around the neck. Thus, a rotating chair is needed to elicit proper cervical rotation while keeping the head fixed. The chair that was developed for this project was able to rotate to the specified amplitude (±0.5º of accuracy) and frequency. The parameters of the rotation amount, frequency, and amplitude can be adjusted as desired by the project guidelines. Our project aimed to improve upon existing chair models and develop a chair that can be used to assess the COR in neck pain populations.

Vestibular function in families with inherited autosomal dominant hearing loss

The inner ear contains the developmentally related cochlea and peripheral vestibular labyrinth. Given the similar physiology between these two organs, hearing loss and vestibular dysfunction may be expected to occur simultaneously in individuals segregating mutations in inner ear genes. Twenty-two different genes have been discovered that when mutated lead to non-syndromic autosomal dominant hearing loss. A review of the literature indicates that families segregating mutations in 13 of these 22 genes have undergone formal clinical vestibular testing. Formal assessment revealed vestibular dysfunction in families with mutations in ten of these 13 genes. Remarkably, only families with mutations in the COCH and MYO7A genes self-report considerable vestibular challenges. Families segregating mutations in the other eight genes do not self-report significant balance problems and appear to compensate well in everyday life for vestibular deficits discovered during formal clinical vestibular assessment. An example of a family (referred to as the HL1 family) with progressive hearing loss and clinically-detected vestibular hypofunction that does not report vestibular symptoms is described in this review. Notably, one member of the HL1 family with clinically-detected vestibular hypofunction reached the summit of Mount Kilimanjaro.