housing 14 comprises a cannula 21 which projects outwardly of and forms a part of housing 14 this cannula is an inverted u shaped channel extension for channel 16 extending longitudinally outwardly of housing 14 channel 16 and its extension formed by cannula 21 provides a track for extender 11 which is arranged to be pushed by plunger 22 through channel 16 and cannula 21 underneath the edge of a toenail as hereinafter explained as noted from fig1 and 2 plungers 18 and 22 comprise a single structure secured together by a handle 23 and move in unison into and out of channels 15 and 16 handle 23 formed of a suitable plastic material is large enough to be comfortable in a practitioner 39 s hand and still allow sufficient grip to force the cannula between the nail and nail bed of the patient channels 15 and 16 of housing 14 should be large enough to contain adhesive 19 and nail extender 11 respectively for simultaneous application so as to reduce the steps of treatment to a minimum extender 11 is usually formed of a thin firm flexible plastic material which may be cut or filed without splitting the material now used for making artificial fingernails could be used for manufacturing these extenders thus the prosthetic device 10 comprises a dual purpose medical instrument for forcing a cannula between an edge of a toenail and the toe to retrieve the edge of a toenail from its position in the flesh of.