Evaluation of retroauricular skin mobility for bone-anchored solutions.

Background: A subset of patients with bone-anchored hearing aids develop skin reactions that may be related to excess skin mobility around the skin-penetrating abutments. However, there is a lack of reports on the extent of skin mobility within the retroauricular space, typical for the implant location. Methods: This study was based on photographic analysis of the relative shifts between the skull and soft tissue of the head in the retroauricular region, detected under the physiological conditions of head support and facial muscle contraction. Results: The mean calculated value for skin shifts at the implant site was 5.1 mm. In 84 per cent of cases, the extent of skin shift was greater with the head at rest, by an average of 3.1 mm. The extent of skin movement during facial muscle contraction ranged between 0 mm and 8.9 mm. No direct correlations were detected between the extent and direction of skin shifts and patients' age, gender or body mass index. Conclusion: There are no objective data that can predict individual skin movement at the osseointegrated implant site. The study confirmed high variability in terms of the direction and extent of skin shift, which should be discussed when managing related skin problems. [ABSTRACT FROM AUTHOR]