[Diagnosis and therapy of stapes fractures and luxations]

Injuries of the ossicular chain have various etiologies. Skull traumas from blows to the temporal, parietal or occipital region with or without fracture of the temporal bone are the main causes of the ossicular injury; other modes of injury are rare. It depends on the type of trauma which kind of injury occurs. Mainly subluxations, luxations and fractures are to be observed. The incus is the ossicle which is the most often injured. Mostly, only one ossicle is injured, rarely two or all of them.

From January 1997 to June 1999 we operated 19 patients with traumatic lesions of the membrane and the middle ear. In 4 cases the reason for the operation was an injury of the stapes. We observed 2 cases with broken stapes crura, 1 case with an impression of the stapes into the vestibulum with perilymphatic fistula and 1 case with subluxation of the stapes in the direction of the promontorium. By presenting 4 cases we want to point out the diagnostic possibilities and the operative management of such rare injuries. In all cases we applied the transmeatal approach for the operation of the middle ear. In 2 cases it was possible to place the stapes back in their anatomic position in order to re-establish the ossicular chain. In the other 2 cases we had to use middle ear prostheses which were interpositioned between the manubrium of the malleus and the footplate of the stapes.

In all cases the immediate post-operative hearing results and the long-term hearing results after 10 to 28 months were satisfying. We did not notice any post-operative complications, especially no vestibular symptoms. One patient's tinnitus was the same as before the operation.

The diagnosis of a stapes injury is despite the use of sophisticated technology, especially the CT-scan of the temporal bone, often very difficult. A sensitive anamnesis seems to be very important. It depends on the kind of injury which operative technique is to be applied in order to re-establish the ossicular chain. In our opinion, it is useful to take - if it is possible - the autolog stapes for the surgical re-establishment of transmission.