Copyright by Stryker






Sterilization

The parts, once sealed, are sent to the Irish or French vendor for sterilization where they are exposed to a predefined gamma radiation dose. The sterilization process is used to destroy bacteria or other contaminants that may harm cells or tissue when the implant is placed in a patient’s body.

Gamma radiation:

The main advantage of sterilizing medical devices by gamma radiation lies “in its ability to penetrate thick walled packaging materials without inducing radioactivity in the material which is being irradiated”[1]. Gamma radiation is the most energetic form of electromagnetic radiation, having very short wavelengths. It kills microorganism by destroying the DNA bond of molecules and hence prevent their further survival. Gamma rays are usually emitted from a cobalt-60 source.

Industrial sterilization

The figure below shows a typical construction of a pallet irradiation process. Pallets of Stryker products are entering the building (1), are inspected (2) and then automatically transported to the sterilization chamber (3). Once arrived, they are passing a labyrinth system(4), composed of a belt conveyor with several loops. Thereby, the pallets are dipped into a pool, the ionization unit (5), where the packages are sterilized. Finally, the products are stored (6) and are waiting for transportation.

 

[2]

  

[1] Tarpley W., Ilavsky J., Manowitz B., Horrigon R., “Radiation sterilization - The effect of high energy radiation from kilocurie radioactive sources on bacteria”, Journal of Bacteriology, 65 (3): 226 – 354, 1953

[2] Ionisos - Sterilization Company and Partner of Stryker, http://www.ionisos.fr, visited on 07.08.2007