Medical delivery system

A medical delivery system comprising:

• a cartridge with a distal end closed by a flexible membrane and a proximal end connected by a wall forming a vessel containing a liquid medicament,
• a plunger received in the proximal end of the vessel and moved along the vessel in order to expel the fluid medicament, the plunger having a front wall in contact with the fluid medicament and an opposite back wall, which back wall is provided with a spherical or semi spherical shaped cavity fully encapsulated in the interior of the plunger and connected to the back wall of the plunger through an open orifice,
• a plunger rod which can be moved forward inside the vessel in order to move the plunger forward and which plunger rod is disconnectable connected to the plunger,
• the disconnectable connection between the plunger and the plunger rod being obtained by a spherical or semi spherical portion provided at a distal end of the plunger rod engaging the spherical or semi spherical shaped cavity of the plunger,
• characterized in that, the open orifice has a substantially circular cross section provided with protrusions.

A medical delivery system comprising:

• a cartridge with a distal end closed by a flexible membrane and a proximal end connected by a wall forming a vessel containing a liquid medicament,
• a plunger received in the proximal end of the vessel and moved along the vessel in order to expel the fluid medicament, the plunger having a front wall in contact with the fluid medicament and an opposite back wall, which back wall is provided with a spherical or semi spherical shaped cavity fully encapsulated in the interior of the plunger and connected to the back wall of the plunger through an open orifice,
• a plunger rod which can be moved forward inside the vessel in order to move the plunger forward and which plunger rod is disconnectable connected to the plunger,
• the disconnectable connection between the plunger and the plunger rod being obtained by a spherical or semi spherical portion provided at a distal end of the plunger rod engaging the spherical shaped cavity of the plunger,
• characterized in that, the open orifice has a non-circular cross section.