Arkansas BAHA experience: transcalvarial fixture placement using osseointegration surgical hardware.

OBJECTIVE

To determine what factors increase the likelihood of osseointegration failure and implant extrusion with the use of osseointegration surgical hardware, for bone-anchored hearing aids (BAHAs), in children and adults.

PATIENTS

A total of 60 patients (42 pediatric [≤19 yr] and 18 adult patients [34-69 yr]) who received osseointegration surgical hardware for a BAHA at Arkansas Children's Hospital from October 2003 to May 2009 or at the University of Arkansas for Medical Sciences from November 2005 to May 2009, respectively.

INTERVENTION

BAHA placement using 3- and 4-mm fixtures.

MAIN OUTCOME MEASURES

Osseointegration failure with implant extrusion.

RESULTS

Fifty-seven loaded fixtures in the pediatric population, and 20 were placed in the adults. We had a 21% pediatric and 0% adult osseointegration failure rate.

CONCLUSION

Young age, syndromic status, and failure to penetrate the inner table of the cranium increased the risk of osseointegration failures in children. In some cases, skull thickness provides an inadequate amount of bone for 4-mm fixture placement requiring placement of a 3-mm fixture instead. In these cases, transcalvarial placement of the implanted fixture may decrease the extrusion rate as 3-mm fixtures have been associated with increased rates of implant extrusion. The 3-mm fixtures that were placed in a transcalvarial fashion had a decreased extrusion rate compared with 3-mm fixtures that were surrounded by bone and did not penetrate the inner table of the cranium. Individual patient factors out of the surgeon's control likely play a large role in osseointegration failures as well. This clinical case report encourages transcalvarial fixture insertion when using 3-mm fixtures during placement of osseointegration surgical hardware for BAHAs.