Patent ID: 7691087

Claim:
An injection device for use with a probe having a longitudinally-extending passageway to treat muscle tissue of a mammalian body comprising a tubular member adapted for use with the probe and having an external diameter for permitting insertion into the passageway of the probe and an internal diameter, a needle assembly slidably disposed in the tubular member and having a central portion provided with an external diameter, the tubular member and needle assembly having respective proximal and distal extremities, the distal extremity of the needle assembly being provided with a needle and being extendable from the distal extremity of the tubular member and means carried by the proximal extremities of the tubular member and needle assembly for locking the proximal extremity of the needle assembly relative to the proximal extremity of the tubular member, the external diameter of the central portion of the needle assembly approximating the internal diameter of the tubular member and the needle assembly having a column strength when locked within the tubular member so that the needle assembly does not buckle within the tubular member during puncture of the muscle tissue by the needle and thereby limit retraction of the needle assembly relative to the tubular member during puncture of the muscle tissue and provide substantially one-to-one movement between the proximal and distal extremities of the needle assembly.