Needle for invasive medical use and needle assembly

An injection needle for invasive medical use, comprising:

• a needle shaft having a distal end forming a tissue piercing beveled end and a proximate end having a hub;
• a flexible joint with a notch forming a gap within the needle shaft, the gap positioned a distance away from the beveled tip not more than the diameter of the shaft;
• a displacement sensor associated with the notch for detecting and signaling a displacement of the beveled end relative to the rest of the shaft resulting from a force applied to the beveled end when the beveled end is moved into contact with body tissue;
• and
• a signal conductor to transmit detected signals from the displacement sensor.

An injection needle for invasive medical use, comprising:

• a needle shaft having a hollow body with opposed distal and proximal ends and a lumen, the distal end forming a tissue piercing beveled end, and the proximate end having a hub;
• a notch extending through an outermost exterior surface of the body towards a central axis of the body, the notch in fluid communication with the lumen, the notch positioned adjacent the beveled end whereby the beveled end is displaceable relative to a remainder of the body by flexible bending of the body at the notch when the beveled end is pressed against body tissue;
• a displacement sensor associated with the notch to detect and signal a displacement of the beveled end relative to the remainder of the body;
• and
• a signal conductor extending away from the notch to transmit detected signals from the displacement sensor exterior to the body when the beveled end is pressed against body tissue inside the body.