Hand-piece for injection device with a retractable and rotating needle

摘要

An injection device is arranged and constructed to simultaneously rotate a needle during its forward translation as a therapeutic agent such as a liquid is ejected therefrom. In one embodiment the injection device is an automatic device including a pump forcing the liquid through a tube to a hand-piece. The needle has a first position in which it is disposed within a housing of the hand-piece, and a second position in which the needle extends outwardly of the hand-piece so that it can be used to eject the liquid, with the needle being automatically uni- or bi-directionally rotated as it is advanced between the first and second positions. In an alternate positions a syringe is provided with a barrel, a plunger extending into the barrel to eject the liquid through the needle, and a plunger which is pushed into the barrel by the operator.