Patent ID: 7081123

Claim:
A bone marrow aspiration instrument comprising: an elongated tubular cannula having an axially extending lumen therethrough and having distal and proximal ends; a handle body secured to the proximal end of said cannula, said handle body being provided with wing portions extending outwardly from to the axis of said cannula and defining a rounded cavity aligned with and open to the proximal end of said cannula, said handle further defining a stem positioned opposite said rounded cavity and extending away from said cavity and surrounding said cannula, each wing portion defining a lower outwardly curved lower surface and an upper planar surface, a stylet comprising a solid metal elongated shaft having a sharpened tip on one end and an anvil striking portion formed on its other end, said anvil portion being generally cylindrical with one end tapering to said shaft and the other end forming a planar striking surface, a stylet handle secured to said stylet on its proximal end, said stylet handle defining a rounded projection which seats in said cannula handle cavity and wing portions seated upon said cannula handle body wing portions upper planar surface, said elongated stylet shaft being slidably received within said cannula lumen, said stylet sharpened distal tip extending distally from the distal end of said cannula when said stylet is mounted in cannula lumen, locking means mounted in said cannula handle retaining said stylet in said cannula so that force may be applied to the striking surface of said elongated stylet positioned in said cavity without relative rotation between said elongated stylet and said elongated cannula, said handle body and said stylet handle when mounted together having a greater surface area located on one side of said cannula axis and a minor surface area located on an opposite side of said cannula axis so that both handle bodies are eccentrically mounted on the axis of said cannula.