Frank's Needle

Needle Franca ( lat. Acus Franki ) - a medical tool for piercing the skin and taking blood. At present, they are not used, since scarifiers are primarily used for taking. Using an Frank needle, on average about 1 ml of capillary blood was collected. The name of the needle comes from the name of the German physician K.E. Frank (KE Francke, 1859-1920), who patented the device.

Frank's needle consists of a tubular body to which a trigger is attached to the side. Both ends of the tubular body are threaded. From the side of the sharp part of the tool (tip, hammer), the tip is screwed onto this thread, and on the other hand, the coupling . Using the tip, the protruding point of the striker is controlled, that is, the Frank needle is made in such a way that it is possible to adjust the depth of injection by screwing or unscrewing the tip. The sleeve serves as a stop for the coil spring, which is placed inside the tubular body. At the opposite end from the tip, a head is wound, which is directly involved in the platoon of the striker before the injection. Blood is drawn by pulling the trigger, in which the compressed spring is straightened and, therefore, delivers an injection with the tip of the hammer, the force of which is also adjustable ^[1] .

Frank's needle has many drawbacks. They are related to the fact that the Frank needle refers to reusable instruments, and before each use it must be sterilized , and, as practice has shown, sterilization with alcohol is insufficient (the risk of infection is significantly increased), the instrument must be boiled in water before treatment with alcohol. From frequent boiling, the spring rusts, the point of the striker becomes dull. ^[2]

Most modern blood glucose meters come with similar plastic devices with disposable lancets.