Considering that the neural pathways involved in hearing at no point enter the spine, the claim that chiropractic manipulation can treat neural hearing loss and deafness is both biologically and medically implausible. “Cervicogenic hearing loss”, is a condition which is argued to restrict vertebral arterial blood flow leading to hearing impairment, however there is little empirical evidence for the existence of this condition, and would likely be very rare indeed if it does even exist.
I have reviewed the studies in chiropractic journals most frequently cited by straight (conservative) chiropractors as evidence of the efficacy of chiropractic manipulation of the cervical vertebrae to treat hearing impairments (Alcantara, Plaugher, Klemp, & Salem, 2002; Cowin & Bryer, 2002; Di Duro, 2006; Hülse, 1994; Kessinger & Boneva, 2000; Terrett, 2002), and they are without exception poorly designed, each scoring a 0 out of a possible 5 on the Jadad scale (an independent scoring system for assessing the scientific rigour of clinical studies; Jadad et al., 1996), indicating methodologically “very poor” studies.
These papers typically document the anecdotal account cited by “Dr” Cohen of the first chiropractic manipulation conducted by D.D. Palmer to cure a hearing loss in a janitor of the name of William Harvey Lillard in 1895. Emphasising just why anecdotes are the weakest form of evidence in the scientific arena, details in accounts of the event by D.D. Palmer and Lillard’s daughter, Valdeenia, who reported being present during the first manipulation vary wildly.
As for what is the best treatment for hearing loss and deafness – that depends on the cause. Hearing loss is broadly divided into 2 types – conductive (caused by blockages in the outer to middle ear) and sensorineural (typically nerve damage in the cochlea, but may also include damage to the neural pathways in the brain). A conductive hearing loss may recover over time or with the aid of medical intervention, however a sensorineural hearing loss is usually permanent.
In the case of long-term /permanent hearing losses beyond a certain level of severity, the best proven means of intervention is amplification, either through hearing aids or assistive listening devices such as a set of headphones for watching the TV. For more severe hearing losses, cochlear implantation may be the best course of action in certain individuals. Whether or not a hearing impaired individual receives amplification, there are also a variety of strategies that individuals can be counselled on such as lip reading, recovery tactics, and manipulating the environment to make it easier to hear and understand speech.
Jessica Bennett – Clinical Audiologist