A test of static and dynamic balance function in children with cochlear implants

objectives: To determine the incidence of static and dynamic balance dysfunction in a group of children with profound sensorineural hearing loss receiving a cochlear implant and to assess the impact of cochlear implant activation on equilibrium. Design: Observational cross-sectional study of children with single-sided implants, tested under 2 conditions: (1) implant on and (2) implant off in a random order. Setting: Ambulatory setting within an academic, tertiary care children's hospital. Participants: Forty-one children (ages 4-17 years) with cochlear implants comprised the study group. Fourteen children with normal hearing served as controls. Intervention: All participants performed a standardized test of static and dynamic balance function (Bruininks-Oseretsky Test of Motor Proficiency 2 [BOT2], balance subset). Children with implants performed the BOT2 under the 2 randomized conditions. Main Outcome Measures: Overall performance on the balance subset of the BOT2 and the influence of implant activation on performance. Results: The mean (SD) age-adjusted scale score for our control group was 17 (5) points (95% confidence interval [CI], 14-20), which was not significantly different (P=.15) from the published age-adjusted mean for the BOT2 balance subset (15 [5] points). The group that had undergone implantation, however, performed significantly more poorly (1216] points; 95% CI, 10-14) than either the control group or the published test mean (P=.004). Children with implants performed better with their implants on than with their implants off (mean [SD] difference, 1.3 [2.7] points; 95% CI, 0.3-2.3; P=.01). Conclusions: Large differences exist in the balance ability of children with sensorineural hearing loss requiring cochlear implantation compared with age-matched controls. Implant activation, however, conferred a slight advantage in accomplishing balance-related tasks. These results substantiate the need to further quantify the baseline vestibular dysfunction of our study population of children with cochlear implants, as well as the impact of implant activation on the input and output of the vestibular system.