The Rinne test is a clinical screening examination used to quickly assess a person’s hearing. It differentiates between conductive and sensorineural hearing loss. The test compares a patient’s perception of sound transmitted by air against sound transmitted directly through the skull bone. This comparison provides insight into where a potential issue in the auditory system might be located.
Understanding Air and Bone Conduction
The human ear uses two distinct pathways to transmit sound energy to the inner ear: air conduction (AC) and bone conduction (BC). Air conduction is the primary and most efficient method, involving sound waves traveling through the ear canal, vibrating the eardrum and middle ear bones. This mechanical vibration is then passed on to the fluid-filled cochlea in the inner ear, where it is converted into electrical signals for the brain.
Bone conduction is a secondary pathway where vibrations bypass the outer and middle ear structures entirely. Sound is transmitted directly through the bones of the skull, such as the mastoid process, to stimulate the cochlea. In a person with normal hearing, the outer and middle ear acts as an amplifier, making air-conducted sound significantly louder and longer-lasting than bone-conducted sound. This difference, where AC is perceived as better than BC, establishes the normal reference point for the Rinne test.
Step-by-Step Guide for Performing the Test
The Rinne test requires a quiet environment and a 512 Hz tuning fork. This frequency is preferred for evaluating hearing loss. The examiner activates the tuning fork by striking it against a firm surface, such as their knee or elbow, to set the tines into vibration.
The initial step involves testing bone conduction (BC) by placing the stem of the vibrating fork firmly against the mastoid process, the bony prominence just behind the ear. The patient indicates when they can no longer hear the sound transmitted through the bone.
Once the patient signals the sound has stopped, the examiner immediately lifts the still-vibrating fork and moves it to the external auditory canal. This second position measures air conduction (AC), with the tines held one to two centimeters from the ear canal opening. The patient is asked if they can hear the sound again. The examiner compares the duration or loudness of the sound perceived via AC and BC for the tested ear, and the sequence is repeated on the opposite ear.
Analyzing the Rinne Test Results
The interpretation of the Rinne test relies on the patient’s comparison of air conduction (AC) and bone conduction (BC).
Rinne Positive Result (AC > BC)
When a patient reports hearing the sound longer or louder next to the ear canal than on the mastoid bone, this is a “Rinne positive” result. This is the normal finding, reflecting the auditory system’s natural efficiency in transmitting sound through the outer and middle ear structures. A positive result can also occur with sensorineural hearing loss (damage to the inner ear or auditory nerve). In this scenario, both AC and BC are diminished, but AC remains perceived as better than BC because the outer and middle ear pathway is structurally intact.
Rinne Negative Result (BC > AC)
A “Rinne negative” result occurs when the patient hears the sound longer or louder on the mastoid bone than next to the ear. This abnormal result indicates conductive hearing loss in that ear. Conductive hearing loss involves a problem in the outer or middle ear—such as fluid, a perforated eardrum, or wax buildup—that physically blocks the efficient transmission of sound waves to the inner ear. Since the bone conduction pathway bypasses this blockage, the sound transmitted through the skull is perceived as louder than the sound traveling through the obstructed air pathway.