Patent ID: 7300416
Filing Date: 2007-11-27
Classification: A61M

Abstract:
1. A method for providing an injection from a medical device, comprising the steps of: providing a medical device comprising a barrel, a retractable needle, a mounting stem having a connector that is cooperable with a cartridge containing a quantity of medicinal fluid, wherein the mounting stem is spaced apart from the barrel to provide an annular passage, the mounting stem extending longitudinally within the barrel along a majority of a length of the barrel, and the device comprises a radial member connected with the mounting stem and releasably engaging a recess in the barrel to retain the stem in a fixed axial position relative to the barrel during an injection; providing a cartridge containing a quantity of medicinal fluid, comprising a fluid container and a seal comprising a connector cooperable with the connector on the stem; attaching the cartridge to the mounting stem by connecting the seal connector with the stem connector; displacing the fluid container forwardly through the annular passage until the fluid container engages the radial member, whereby while the fluid container is displaced forwardly the stem maintains the seal in a fixed axial position, relative to the barrel; displacing the fluid container further forwardly after the fluid container engages the radial member so that the fluid container displaces the radial member, disengaging the radial member from the recess and effecting release of the needle; and retracting the needle after release via a biasing element biasing the needle rearwardly.