Surgical instrument for impact insertion of an intraosseous trocar-needle
First Claim
1. A surgical instrument for forcefully driving a trocar needle into a patient'"'"'s bone through the skin and the tissue by the force of an expanding helical spring, and for releasing said trocar needle for connection of a syringe, an infusion or medication set to said trocar needle, the instrument including:
- a longitudinal housing having a front end and a rear end, said housing being in the shape of a hollow cylinder including a smooth bore extending from its rear end to a stop close to its front end,a screw cap closing the rear end of said housing, said screw cap having a rear portion extending beyond the rear end of said housing,a trocar needle having a sharp front end for penetrating said bone and a rear end surrounded by an outstanding connecting flange, said needle being positioned, in a cocked state, in said housing with its sharp front end close to the front end of said housing,a bolt slidingly positioned in said housing, having a first front portion provided with means for releasably holding the rear end of said trocar needle, a second portion of a diameter coextensive with said smooth bore in said housing positioned to the rear of said stop, a third portion of smaller diameter, and a rear portion provided with means for being held in said rear portion of said screw cap in the cocked state,safety catch means positioned in said screw cap for engagement with said means for being held to releasably hold said rear portion of said bolt,a helical spring surrounding said third portion of said bolt and being held in a compressed state between said second portion of said bolt and said rear portion of said screw cap,whereby said bolt is shot in a forward direction by the force of said helical spring as it expands when said safety catch means releases said rear portion of said bolt, and is stopped by contact of said second portion with said stop in said housing, effecting release of said trocar needle from the front portion of said bolt.
1 Assignment
0 Petitions
Accused Products
Abstract
A surgical instrument serves to insert a trocar needle into the bone marrow of a patient for connection of a syringe, an infusion set or the like. The instrument includes a cylindrical housing containing a sliding bolt and the trocar needle configured to be forcefully shot through the bone material into the marrow by release of a compressed helical spring. The bolt holds the rear end of the needle in a releasable grip permitting the needle to be released and to remain in the bone. The helical spring is positioned in the rear of the housing and of the bolt and is held in compressed state by a catch which is releasable by pressure on a trigger. This shoots the bolt and the needle forwards, a collar in the housing stopping the bolt sharply and allowing the needle to be released from the device after its penetration and to be connected to a syringe or an infusion set for intraosseous injection, infusion or other treatment.
326 Citations
14 Claims
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1. A surgical instrument for forcefully driving a trocar needle into a patient'"'"'s bone through the skin and the tissue by the force of an expanding helical spring, and for releasing said trocar needle for connection of a syringe, an infusion or medication set to said trocar needle, the instrument including:
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a longitudinal housing having a front end and a rear end, said housing being in the shape of a hollow cylinder including a smooth bore extending from its rear end to a stop close to its front end, a screw cap closing the rear end of said housing, said screw cap having a rear portion extending beyond the rear end of said housing, a trocar needle having a sharp front end for penetrating said bone and a rear end surrounded by an outstanding connecting flange, said needle being positioned, in a cocked state, in said housing with its sharp front end close to the front end of said housing, a bolt slidingly positioned in said housing, having a first front portion provided with means for releasably holding the rear end of said trocar needle, a second portion of a diameter coextensive with said smooth bore in said housing positioned to the rear of said stop, a third portion of smaller diameter, and a rear portion provided with means for being held in said rear portion of said screw cap in the cocked state, safety catch means positioned in said screw cap for engagement with said means for being held to releasably hold said rear portion of said bolt, a helical spring surrounding said third portion of said bolt and being held in a compressed state between said second portion of said bolt and said rear portion of said screw cap, whereby said bolt is shot in a forward direction by the force of said helical spring as it expands when said safety catch means releases said rear portion of said bolt, and is stopped by contact of said second portion with said stop in said housing, effecting release of said trocar needle from the front portion of said bolt. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
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Specification