Device for mixing and injecting a composition, in particular a bone cement

A device to mix and inject a composition, comprising:

• a vessel comprising a cylindrical wall, a first end and a second end, the vessel defining an inner chamber and having a longitudinal axis, the vessel further comprising a tapped opening at the first end and an outlet at the second end;
• a piston assembly comprising a threaded rod, a handle located at a first end of the threaded rod and a piston head located at a second end of the threaded rod;
• the threaded rod cooperating with the tapped opening of the vessel, the thread rod extending along the longitudinal axis of the vessel, and the threaded rod comprising two longitudinal ends and a longitudinal internal channel between the two longitudinal ends;
• the piston head being arranged in the inner chamber of the vessel, the piston head comprising a cross-section whose shape is complementary to that of a cross-section of the cylindrical wall of the vessel, the piston head comprising a through-hole in a continuation of the longitudinal internal channel of the threaded rod;
• the handle of the piston assembly comprising a through-cavity in an extension of the longitudinal internal channel of the threaded rod;
• a mixing assembly comprising a rod, a handle located at a first end of the rod, and a mixing paddle located at a second end of the rod, the rod of the mixing assembly extending into the longitudinal internal channel of the threaded rod and into the through-hole of the piston head of the piston assembly, the mixing paddle being arranged in the inner chamber of the vessel;
• wherein the rod of the mixing assembly is an elongate body comprising an outer helical groove;
• and
• wherein the longitudinal internal channel of the threaded rod of the piston assembly comprises an inner helical rib, the outer helical groove cooperating with the inner helical rib of the longitudinal internal channel of the threaded rod of the piston assembly.

Device to mix and inject a composition, comprising:

• a vessel comprising a cylindrical wall, a first end and a second end, the vessel defining an inner chamber and having a longitudinal axis, the vessel further comprising a tapped opening at the first end and an outlet at the second end;
• a piston assembly comprising a threaded rod, a handle located at a first end of the threaded rod and a piston head located at a second end of the threaded rod;
• the threaded rod cooperating with the tapped opening of the vessel, the thread rod extending along the longitudinal axis of the vessel, and the threaded rod comprising two longitudinal ends and a longitudinal internal channel between the two longitudinal ends;
• the piston head being arranged in the inner chamber of the vessel, the piston head comprising a cross-section whose shape is complementary to that of a cross-section of the cylindrical wall of the vessel, the piston head comprising a through-hole in a continuation of the longitudinal internal channel of the threaded rod;
• the handle of the piston assembly comprising a through-cavity in an extension of the longitudinal internal channel of the threaded rod;
• a mixing assembly comprising a rod, a handle located at a first end of the rod, and a mixing paddle located at a second end of the rod, the rod of the mixing assembly extending into the longitudinal internal channel of the threaded rod and into the through-hole of the piston head of the piston assembly, the mixing paddle being arranged in the inner chamber of the vessel;
• wherein the rod of the mixing assembly is an elongate body comprising an outer helical groove;
• and
• wherein the longitudinal internal channel of the threaded rod of the piston assembly has a smooth appearance and a cross-section larger than a cross-section of the rod of the mixing assembly, the through-cavity of the handle of the piston assembly has a cross-section smaller than the cross-section of the longitudinal internal channel of the threaded rod of the piston assembly and comprises an inner helical rib, the outer helical groove cooperating with the inner helical rib of the through-cavity of the handle of the piston assembly.