Weber's test demystifiedBMJ 2002; 325 doi: https://doi.org/10.1136/bmj.325.7372.1117 (Published 09 November 2002) Cite this as: BMJ 2002;325:1117
Physics renders Weber's test not so mysterious …
- Chima E Mbubaegbu, consultant orthopaedic surgeon. (firstname.lastname@example.org)
- Homerton University Hospital NHS Trust, London E9 6SR
- Department of Otorhinolaryngology, Faculty of Health Sciences, University of Stellensbosch, 7505 South Africa
EDITOR—Weatherall's mystery—a positive Weber's test in the normal ear in unilateral sensorineural hearing loss but in the affected ear in unilateral conductive hearing loss—has baffled many neurologists and ear, nose, and throat surgeons for some time; I wonder whether my explanation would convince him.1
The word conduction is used confusingly by ear, nose, and throat surgeons and neurologists to describe normal transmission of sound from the outside world to the ear. Everything apart from the sensorineural aspect of the hearing is thought to be conductive. The sound is normally conducted (transmitted) through the air through the external ear into the middle ear. This makes air a better sound conductor (when defined this way) than a solid object.
It is, however, clear to any engineering student that bone or any denser object is a better conductor of sound than is air. When the tuning fork is placed directly …