An apparatus for targeting and forming drill channels in the tibia in the area of a knee joint during reconstruction of an anterior cruciate ligament, having a handle, which includes a drill sleeve for configuring a first target point on the tibia and an arm extending beyond the distal end of the drill sleeve for determining a second target point on the tibial plateau. To provide an apparatus for targeting and forming drill channels in the tibia that is adaptable to the patient's individual anatomical idiosyncrasies, it is proposed that at least one portion of the arm should be configured as elastically reshapable.