A needle shield is provided for a medical device having a needle cannula. The needle shield includes a guard (40) that is slidably movable along the needle cannula from a proximal position where the tip of the needle cannula is exposed to a distal position where the tip of the needle cannula is shielded. A hinged arm (51) connects the guard to the proximal end of the needle cannula. The hinged arm can be collapsed upon itself, such that the guard is adjacent to the proximal end of the needle cannula. The hinged arm can be extended to cause the guard to move distally along the needle cannula and into a position for shielding the tip of the needle cannula. Structure is provided to prevent excessive additional rotation of the hinged elements of the hinged guard after the tip of the needle cannula is shielded.
