[History of the reflex hammer].

The knee jerk was first described by Erb and Westphal in 1875. In subsequent years neurologists used direct finger taps and light-weight chest percussion hammers, but these proved to be inadequate for eliciting muscle stretch reflexes. The first hammer specially designed for eliciting such reflexes was the triangular reflex hammer introduced by John Madison Taylor in 1888. Over the next 25 years several popular reflex hammers were designed, some of which are still in use. These include the Babinski hammer with a round head fixed perpendicular to the shaft, and Rabiner's modification where the head can also be attached parallel to the shaft.