A cannula (1) comprising a central axis (2), a front end (3) and a through channel (5) coaxial or parallel to said central axis (2) and defining a peripheral wall (12) of said cannula (1), wherein A) said cannula (1) further comprises at least two perforations (8) penetrating said peripheral wall (12) transversely to said central axis (2); B) said through channel (5) is open at said front end (3); and C) the cross section of said through channel (5) has a contraction (6) with a diameter di located between the front most of said at least two perforations (8) and said front end (3) which is formed as a guidance for a wire (7). A device (10) for liquid jet irrigation of bone comprising such a cannula (1) and a wire (7).