The invention relates to a medical instrument with a hollow shaft, a handle, and a tool, where at least one jaw member of the tool can be rotated in relation to the at least one other jaw member of the tool for purposes of opening and closing by means of one rotatably configured gripping member of the handle, and the rotatable jaw member and the gripping member of the handle that serves to rotate are connected to one another by means of a push pin installed in the hollow shaft. To create a simple construction ensuring the best possible power transmission along with a good cutting sensation for the operator, a rigid casing can be inserted into the push pin, at least partly in form-locking connection, which casing in turn can be inserted, at least partly in form-locking connection, into the hollow shaft and the push pin is mounted in the casing so that it is at least partly rotation-resistant.