Bone Conduction is the conduction of sound directly to the inner ear through the bones of the skull thus bypassing the outer and middle ear.  

This type of hearing assessment should be performed as part of a full Pure Tone Audiometry to assess from where the issues with hearing are likely to originate." Where Bone Conduction and Air Conduction match the indication is that the hearing issue is in the inner ear. Where there is a discrepancy, and the thresholds have been verified with masking, the indication is that the hearing problem lies within the outer or middle ear.

Performing Bone Conduction assessment is done by placing a Bone Conduction headset onto the mastoid prominence of the worse hearing ear and placed as near to the pinna as possible, without touching it. Determining the threshold should be done in the same way as obtaining the Air Conduction thresholds is performed.