Comparison in Balance Between Young Adults With and Without Hearing Impairment

Hearing impairment (HI) affects 1.4 per 1000 newborns in the United States (CDC, 2015). Damage to the vestibular system is one of the major causes of HI and is associated with balance impairment. Balance deficits may interfere with the development of motor skills. There is some discrepancy in the current literature on the development of balance in children and adolescents with HI. Few studies have investigated whether balance is impaired in young adults with HI and their results are inconsistent. The purpose of this study is to compare balance between young adults with and without HI. Methods: A total of 70 participants were recruited for this study, 35 with HI (25.29 ± 2.71 years) and 35 without HI (24 ± 2 years). Balance outcomes were assessed using computerized dynamic posturography and the long forceplate (NeuroCom Internationa, Clackmas, OR, 2010). Balance tests included Sensory Organization Test (SOT), Motor Control Test (MCT), Adaptation Test (AT), and Unilateral Stance (US). Independent T-tests were used to analyze differences in balance between young adults with and without HI. Results: Significant differences were found in the SOT composite score between those with and without HI (t (68) = -4.99; p0.05). When the tests required the use of the vestibular system to maintain balance, the results indicate significant impairment for participants with HI. This was evident when balancing on an unstable surface with eyes open [EO] (t (68) = -2.19; p0.05) and closed [EC] (t (68) = -4.32; p0.05), as well as balancing on an unstable surface with incorrect visual information (t (68) = -6.17; p0.05). A significant difference was also found in the single leg stance. The participants with HI showed significantly higher sway velocity (degree/sec) during EO and EC conditions on both the right and left leg (t (68)= Right leg EO: 3.32, Right leg EC: 5.40, Left leg EO: 2.84, Left leg EC: 6.33; p0.05), which indicated unstable balance compared to controls. No difference was found between the two groups for the MCT and AT. Conclusion: The results showed that there are differences in balance between young adults with and without HI. When a test required increased use of the somatosensory and vestibular system participants with HI had more sway and were able to balance on one leg for less time than young adults without HI.