A new single-use bone marrow biopsy needle.

Abstract

A new needle for taking a bone marrow biopsy sample from the posterior iliac crest is described. The needle comprises a hollow tube having a front-end portion formed to a reduced diameter. The front end is tapered by means of circumferentially spaced facets, forming a cutting edge. A series of flutes/serrations are introduced at the tapering transitional portion, between the main wider portion of the hollow tube and its reduced-diameter front-end portion. This design is new and is not available in any other conventional biopsy needle. These serrations help in its penetration through the hard cortical bone. A spacer guide, which is placed between the plastic dome of the needle and the stilette cap to enhance the ergonomics, is also new. The inside of the spacer guide is funnel shaped, through which the stilette is passed, thereby ensuring an easy and accurate alignment of the distal ends of the hollow needle and the stilette. This technique facilitates removal of the biopsy sample rearwardly out of the hollow needle particularly when the mouth (distal-end opening) of the needle is covered by extraneous bony soft tissue. In this technique, the same stilette that occupies the needle during its entry into the marrow cavity is used in sample removal. Thus, the need for an additional pusher to remove the biopsy sample from within the lumen of the needle has been eliminated.