Implantable electro-mechanical devices for sensorineural hearing loss. Implantable electro-mechanical devices are a valuable solution for patients with sensorineural hearing loss who do not tolerate a conventional hearing aid. The currently available devices are the result of technological progress and clinical experiments over the last 30 years. The advantages observed during early clinical trials are nowadays confirmed. Some issues – specifically the coupling of the device to the human auditory system – are still open for improvement.