[Ossicular chain injury due to the head trauma].

Nineteen cases of ossicular chain separation and ossicular dislocation due to head injury were presented. These cases were operated at an early stage after the trauma. The malleus was almost always involved in ossicular chain injury, while the incus was involved in 42% of our cases. The stapes was involved in 21%. The incudo-mallear joint is always separated while the incudo-stapedial joint is separated less than 50% of our cases. We thought that the incudo-mallear joint suffered some damage from the dynamic action due to the warp of temporal bone fracture and the shock given to the tympanic membrane transmitted to the malleus directly. The surface of incudo-mallear joint is wide, therefore, complete separation of this joint is thought to hardly occur. The malleus does not dislocate so widely because it is fixed with tympanicmembrane and the tensor tympanic muscle. We get the different results from the past reports. By doing early surgery, we could observe the change of the ossicular chains before natural recovery occured.