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.

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.

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.

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.

To compare the skin-related complications of the traditional skin flap method with a linear incision method of implantation.

All cases of bone-anchored hearing aid surgery performed by a single surgeon (n = 117) were compared over two periods: 1999–2011, when the traditional method of skin flap and soft tissue removal was used (group 1; n = 86), and 2012–2013, when linear incision without soft tissue removal was used (group 2; n = 31). All patients were followed up for one year and complications were recorded for that period.

There were 21 (24.4 per cent) skin-related complications in group 1 (skin overgrowth = 12, wound infection = 8 and numbness = 1) and 3 (9.7 per cent) complications in group 2 (wound infection = 3). Analysis using independent t-tests showed the results to be significant (p < 0.05; 95 per cent confidence interval = 0.0800–0.4473).

The linear incision without soft tissue removal method for bone-anchored hearing aid implantation reduces skin complication rates.

To report a case of successful bone-anchored hearing aid implantation in an adult patient with type III osteogenesis imperfecta, which is commonly regarded as a contraindication to this procedure.

A 45-year-old man with type III osteogenesis imperfecta presented with mixed hearing loss. There was a mild sensorineural component in both ears, with an air–bone gap between 45 and 50 dB HL. He was implanted with a bone-anchored hearing aid. The audiological outcome was good, with no complications and good implant stability (as measured by resonance frequency analysis).

To our knowledge, this is the first recorded case of bone-anchored hearing aid implantation in a patient with osteogenesis imperfecta.

The loading of bone-anchored hearing system sound processors usually occurs two to three months after surgical implant. This study examined a new bone-anchored hearing system coupling mechanism that permits loading at two weeks post-implantation without compromising osseointegration.

Twenty implants were implanted into 15 patients. The interval between operation and time of processor loading was recorded, along with the cause of any delay and any late complications.

Two patients were fitted with implants at seven and nine weeks. The delay was a result of administrative errors; the patients reported no skin problems. Of the remaining 17 implants, 8 processors were fitted at 2 weeks, 1 at 3 weeks, 4 at 4 weeks, 3 at 7 weeks and 1 at 8 weeks. For those nine implants fitted later than two weeks, the delay was because of incomplete skin healing.

The Oticon Medical Xpress system allowed processor loading at two weeks post-operatively, providing skin healing was adequate. Early loading occurred in approximately half of the patients. All patients were fitted within the two to three months traditionally allowed. Prolonged skin healing time was the main reason for the delayed fitting of sound processors.

This study compared the performance of two new bone-anchored hearing aids with older bone-anchored hearing aids that were not fully digital.

Fourteen experienced bone-anchored hearing aid users participated in this cross-over study. Performance of their existing bone-anchored hearing aid was assessed using speech-in-noise testing and questionnaires. Participants were then fitted with either a Ponto Pro or a BP100 device. After four weeks of use with each new device, the same assessments were repeated.

Speech-in-noise testing for the 50 per cent signal-to-noise ratio (the ratio at which 50 per cent of responses were correct) showed no significant differences between the Ponto Pro and the BP100 devices (p = 0.1) However, both devices showed significant improvement compared with the participants' previous bone-anchored hearing aid devices (p < 0.001). There were no significant differences between the two new devices in the questionnaire data.

Both fully digital bone-anchored hearing aids demonstrated superior speech processing compared with the previous generation of devices. There were no substantial differences between the two digital devices in either objective or subjective tests.

Patients receiving a bone-anchored hearing aid have well-documented improvements in their quality of life and audiometric performance. However, the relationship between audiometric measurements and subjective improvement is not well understood.

Adult patients enrolled in the Nova Scotia bone-anchored hearing aid programme were identified. The pure tone average for fitting the sound-field threshold, as well as the better and worse hearing ear bone conduction and air conduction levels, were collected pre-operatively. Recipients were asked to complete the Speech, Spatial and Qualities of Hearing questionnaire; their partners were asked to complete a pre- and post-bone anchored hearing aid fitting Hearing Handicap Inventory for Adults questionnaire.

Forty-eight patients who completed and returned the Speech, Spatial and Qualities of Hearing questionnaire had partners who completed the Hearing Handicap Inventory for Adults questionnaire. The results from the Speech, Spatial and Qualities of Hearing questionnaire correlated with the sound-field hearing threshold post-bone-anchored hearing aid fitting and the pure tone average of the better hearing ear bone conduction (total Speech, Spatial and Qualities of Hearing Scale to the pre-operative better hearing ear air curve (r = 0.3); worse hearing ear air curve (r = 0.27); post-operative, bone-anchored hearing aid-aided sound-field thresholds (r = 0.35)). An improvement in sound-field threshold correlated only with spatial abilities. In the Hearing Handicap Inventory for Adults questionnaire, there was no correlation between the subjective evaluation of each patient and their partner.

The subjective impressions of hearing aid recipients with regards to speech reception and the spatial qualities of hearing correlate well with pre-operative audiometric results. However, the overall magnitude of sound-field improvement predicts an improvement of spatial perception, but not other aspects of hearing, resulting in hearing aid recipients having strongly disparate subjective impressions when compared to those of their partners.

Most of the literature regarding osseointegrated implantation for hearing rehabilitation focuses on the 5.5 mm abutment. This study aimed to add to the data available on the survival of the 8.5 mm abutment, and to describe its utility in obese patients.

To review the outcomes of patients who received a bone-anchored hearing aid implant, and create a model comparing the mechanical forces acting upon combinations of fixture and abutment lengths.

Retrospective chart review and mathematical modelling.

In this retrospective cohort study comprising 25 patients, less abutment overgrowth was observed in the 8.5 mm abutment recipients versus recipients of the 5.5 mm abutment. When the principle of equilibrium of a rigid body was applied, the 8.5 mm abutment was at a calculated mechanical disadvantage compared with the 5.5 mm abutment.

The 8.5 mm abutment may be useful in patients with copious subcutaneous soft tissue as in the obese population. The 8.5 mm abutment has a calculated mechanical disadvantage, potentially putting the implant under greater mechanical stress; however, the clinical relevance of this is unclear.

Numerous techniques have been described to manage the skin and other soft tissues during bone-anchored hearing aid insertion. Previously, generally accepted techniques have sometimes led to distressing alopecia and soft tissue defects. Now, some surgeons are rejecting the originally described split skin flap in favour of a less invasive approach.

To investigate bone-anchored hearing aid placement utilising a single, linear incision with either no or minimal underlying soft tissue reduction.

Thirty-four adults were prospectively enrolled to undergo single-stage bone-anchored hearing aid placement with this modified technique. A small, linear incision was used at the standard position and carried down through the periosteum. Standard technique was then followed with placement of an extended length abutment. Patients were reviewed regularly to assess wound healing, including evaluation with Holgers' scale.

Only 14.7 per cent of patients had a reaction score of 2 or higher. Most complications were limited to minor skin reactions that settled with silver nitrate cautery and/or antibiotics. None required revision surgery for tissue overgrowth, and there were no implant failures.

Our results suggest this to be a simple and effective insertion technique with favourable cosmesis and patient satisfaction.

To outline the management options and neurological complications associated with repeated traumatic falls that cause intrusion of bone-anchored hearing aid abutments.

A three-year-old boy with coloboma, heart defects, atresia of nasal choanae, retarded growth, genital abnormalities, ear defects and deafness was fitted with a bone-anchored hearing aid for severe conductive hearing loss and congenital ear malformations. Six months later, a traumatic fall caused an intrusion injury which rendered the bone-anchored hearing aid abutment unusable. Without removing the original abutment, a second abutment was inserted on the same side to aid his hearing. Two years later, the child fell again and damaged his second bone-anchored hearing aid abutment. Having been offered a surgical option to repair the area, the parents opted to keep the abutments in situ.

Direct trauma to the fixture of a bone-anchored hearing aid is a relatively common long-term complication in children which can disrupt osseointegration and disable the implant. For young children who are either prone to falling or have behavioural problems, a bone-anchored hearing aid Softband may be more appropriate to non-invasively aid hearing.

To investigate microbiological biofilm contamination of retrieved bone-anchored hearing aids.

Nine failed, retrieved bone-anchored hearing aids and 16 internal screws were examined by scanning electron microscopy. A fixture from a failing implant, which had been removed and disassembled under aseptic conditions, was cultured. Finally, an internal screw from a new, unimplanted fixture was examined by scanning electron microscopy.

Debris was seen on the fixture and abutment of all bone-anchored hearing aids, and on the heads of the 16 internal screws. On eight screws, biofilm extended down the shaft to the threads, where it was several micrometres thick. Culture of a failing fixture yielded staphylococcus. The new, unimplanted fixture internal screw showed evidence of scratching and metallic debris on the threads, which may interfere with close fitting of the screw and subsequently facilitate microleakage.

There may be a link between internal microbial contamination and failure of bone-anchored hearing aids.

To investigate the long-term survival rate of bone-anchored hearing aid implants, and to assess the number of patients who stop using their bone-anchored hearing aid.

Patients who underwent bone-anchored hearing aid surgery between September 1977 and December 1986 were identified from a prospective database. Data were collected from patient records.

During the study period, 143 patients were fitted with a bone-anchored hearing aid. Records from 132 patients were found, with a mean follow up of nine years. A total of 150 implants were installed in these patients. A total of 41 implants (27 per cent) were lost during follow up: 17 lost osseointegration, 16 were removed and eight were lost due to direct trauma. At the end of follow up, 119/132 (90 per cent) patients were still using their bone-anchored hearing aid.

Despite a high incidence of implant loss over time, a large number of patients still continued to use their bone-anchored hearing aid.