Skin and soft tissue complications of bone-anchored hearing aids: Introducing a new classification system

There have been significant surgical and technological advances in bone-anchored hearing aid (BAHA) design, function, and implantation technique, but peri-implant skin complications remain the most frequent complication. The most important aspect in dealing with cutaneous complications is to identify the type of cutaneous lesion. Although Holger's Classification has been an extremely useful clinical tool, this grading system has been shown to be unsuitable for some cases. We therefore propose a new consistent and easy assessment classification of cutaneous complications associated with BAHA.

A retrospective clinical study was carried out at a tertiary centre, between January 2008 and December 2014. All patients under 18 years old with a unilateral BAHA were included in the study.

A total of 53 children, with a BAHA, were included in the study. Post-operative skin complications were observed in 49.1% of the patients. Of the children, 28.3% presented with soft tissue hypertrophy, the most frequently reported skin complication, and grading according to the Holger's classification was not considered feasible. To overcome the difficulties we face in clinical practice, a new classification was developed and presented.

The new proposed classification - Coutinho Classification - aims to fill the gaps in the one used currently by introducing new clinical features, most importantly the presence/absence of tissue overgrowth, and by providing a better description of what each category encompasses. This is an inclusive and objective new classification system, maintaining applicability, and useful in guiding the treatment.