a first exemplary embodiment of a device according to the invention that is represented in fig1 to 11 is denoted overall by the reference numeral 10 . the device 10 has a handle 12 , which has an approximately bar - shaped grip 14 . provided at one end of the handle 12 is an opening 16 , which serves for removably receiving a guiding sleeve 18 . as can be seen in particular from the sectional representation of fig7 , the guiding sleeve 18 is formed approximately in the form of a tube 20 , the distal end 22 of which is provided with a serrated rim 24 ( fig1 ). at the opposite end , the guiding sleeve 18 is provided with a rotatable clamping sleeve 26 . in the actual body 28 of the guiding sleeve 18 there is a first , central continuous guiding channel 30 , which in the present case is formed as a central bore passing through the body 28 . the clear inside diameter of the first guiding channel 30 is such that a first aiming wire 32 , as represented in fig1 , can be pushed snugly through it . the aiming wire 32 has an outside diameter of 2 . 4 mm . laterally offset in relation to the first guiding channel 30 there is a second guiding channel 34 , which represents the inner lumen of a guiding tube 36 . the guiding tube 36 is fitted in a recess ( not designated any more specifically here ) on the outer side of the body 28 of the guiding sleeve 18 and fastened therein , for example adhesively bonded or welded or soldered . it is evident from the sectional representation of fig7 that the central longitudinal axis 38 of the first guiding channel 30 runs parallel to and at a distance a from the central longitudinal axis 40 of the second guiding channel 34 . fig1 and the sectional representation of fig7 also reveal that on the outer side of the body 28 there is also a cannulation 42 , to be precise in the form of a cross - sectionally semicircular longitudinal groove 44 . the cannulation 42 is open to an outside laterally to the central longitudinal axis 38 . it can again be seen from the sectional representation of fig7 that a virtual central longitudinal axis 46 of the longitudinal groove 44 likewise lies at a distance a from the central longitudinal axis 38 of the first guiding channel 30 . furthermore , the central longitudinal axis 46 or the longitudinal groove 44 lies exactly diametrically opposite the second guiding channel 34 . in other words , the cannulation 42 or the central longitudinal axis 46 thereof is arranged offset in relation to the second guiding channel 34 or the central longitudinal axis 40 thereof in terms of the circumferential angle by 180 °. returning to the representation of fig1 and 2 , it is evident that an arm 48 , which is held in a mounting 50 , projects from the handle 12 at a distance from and approximately parallel to the guiding sleeve 18 . a clamping lever 54 keeps the arm 48 in the position represented ; pressing of the clamping lever 54 allows the removal of the arm 48 , and it can correspondingly be cleaned or replaced by a new or differently formed arm . the arm 48 has distally a bent region 54 , the distal end 56 of which has an opening 58 . the position of the opening 58 is such that it is in line with the first guiding channel 30 when the guiding sleeve 18 has been pushed into the opening 16 on the handle 12 , as is evident in particular from fig2 . this means that , if a first aiming wire 32 is pushed through the guiding sleeve 18 from proximally , that is a say in the region of the clamping sleeve 26 , it meets the opening 58 and can pass through it . as described and explained in more detail in particular by de 10 2007 057 075 . 0 a1 , the device 10 is set laterally inclined onto the outer side of a bone , for example onto the lower leg bone 64 represented in fig1 . the serrated rim 24 thereby facilitates the setting and holding of the guiding sleeve 18 at this site of the bone 64 or on the skin covering this bone . the distal end 56 of the bent arm 48 is thereby introduced into the opened knee joint and positioned on the tibial plateau 60 such that a first aiming wire 32 pushed through the bone 64 , as is evident in fig1 , passes through the tibial plateau 60 and is passed through the opening 58 . for the sake of overall clarity , the bone is not represented in fig2 , since this first working step is known per se from de 10 2007 057 075 . 0 a1 which is incorporated by reference . the handling and setting of the further aiming wires will now be described and explained in more detail on the basis of the sequence of images of fig3 to fig6 and the sectional representations of fig8 to fig1 . after setting of the first aiming wire 32 , as represented in fig2 , a further or second aiming wire 68 is set through the second guiding channel 34 , as is evident in fig3 or fig9 . it is evident that the first aiming wire 32 is significantly longer than the further , second aiming wire 68 . in its maximum advanced position , the distal tip ( not represented any more specifically here ) of the second aiming wire 68 reaches up to the marking 60 at the distal end 56 of the curved arm 48 . once it has reached this point , that is an indication to the surgeon that the second , further aiming wire 68 has been set in the correct position and in the correct line . then the clamping sleeve 26 is turned , so that the guiding sleeve 18 can be pulled off in the proximal direction ( see arrow 19 ) until the second , further aiming wire 68 has left the second guiding channel 34 , this structural state being represented in fig4 . the length of the pulling - off distance is intended to be represented by the arrow 19 . it is then possible to turn the guiding sleeve 18 about the first aiming wire 32 , as represented in fig4 by the arrow 21 . the turning is carried out through 180 °, so that then the cannulation 42 on the outer side of the guiding sleeve 18 lies in an alignment in which the second aiming wire 68 can enter the cannulation 42 during advancement of the guiding sleeve 18 . this situation is represented in fig5 . if the guiding sleeve 18 is then displaced in the distal direction in a way corresponding to the arrow 32 , the aiming wire 68 enters the cannulation 42 ( see fig1 ). subsequently , the guiding sleeve 18 is pushed through the opening 16 , this opening being designed such that the guiding sleeve 18 can be pushed through either in this position or in the position turned by 180 °. after fixing by the clamping sleeve 26 , a third aiming wire 70 is then pushed through the second guiding channel 34 or the guiding tube 36 , lying on the underside in the representation of fig5 . this situation is represented in fig6 and in fig1 . the third aiming wire 70 can also be advanced until it reaches the corresponding marking 62 at the distal end 56 of the arm 48 , so that again the surgeon can check whether this third aiming wire 70 also protrudes from the tibial plateau 66 at the correct site . subsequently , the guiding sleeve 18 is pulled off and the arm 48 is detached from the handle 12 , so that the entire device 10 is removed from the three set aiming wires 32 , 68 and 70 . this situation is represented in fig1 , that is to say the three aiming wires 32 , 68 and 70 have been pushed through into the lower leg bone 64 from “ below ” by means of the device 10 such that they all three stand up from the tibial plateau 66 aligned parallel to one another . the distance a between the three central longitudinal axes of the three aiming wires 32 , 68 and 70 is chosen such that they can be overdrilled with a 4 . 5 mm drill . this initially involves overdrilling the two outer aiming wires 68 and 70 and subsequently likewise overdrilling the middle aiming wire 32 . this then results in a drilled hole 72 , as represented in fig1 and 14 . if an exactly rectangular channel 74 , as represented in fig1 , is to be achieved , a correspondingly rectangular dilator may be pushed into the drilled hole 72 , in order to detach the protruding regions of bone remaining in the region of intersection . in the reconstruction of an anterior cruciate ligament , a rectangular tendon transplant , for example , with the correct fit and form can then be inserted into the channel 74 and anchored . in fig1 to 21 , a second exemplary embodiment of a device according to the invention is represented , the difference merely being that the guiding sleeve 78 , and correspondingly the opening into which the latter can be pushed into the handle 12 , are formed differently . it can be seen from the sectional representation of fig1 , which corresponds to the sectional representation of fig7 , that here too there is a central , first guiding channel 80 . at the previously described distance a and running parallel to it there is a second guiding channel 82 . here , too , in the outer side of the guiding sleeve 78 there is a first cannulation 84 , the central longitudinal axis of which again runs parallel to and at the same distance a from the central longitudinal axis of the first guiding channel 80 , as described above in conjunction with the first exemplary embodiment . as a departure from the first exemplary embodiment , in the case of the second exemplary embodiment a second and a third cannulation 86 and 88 are also cut out on the outer side of the guiding sleeve 78 . these cannulations again take the form of longitudinally running and laterally open grooves with an approximately semicircular cross section and the central longitudinal axes of which are again at the distance a from the central longitudinal axis of the first guiding channel 80 . as described above , with the second exemplary embodiment three aiming wires running parallel to one another and aligned in a row can be set . in addition , however , it is also possible now to achieve other geometries on resultant drilled holes . fig1 corresponds to a structural state such as that described in fig9 , that is the state after the first two aiming wires 32 and 68 have been set . as is evident from the transition from fig1 to fig1 , after pulling off of the guiding sleeve 78 from the second aiming wire 68 , the latter is turned only by 90 °, as indicated by an arrow 83 . subsequently , the guiding sleeve 78 is pushed in again axially . as a result , the second aiming wire 68 then enters the fourth cannulation 88 , angularly offset anticlockwise by 90 °. a third aiming wire 70 can then be pushed in through the second guiding channel 82 , so that the alignment of the three aiming wires 32 , 68 , 70 at the corners of a triangle resulting from fig1 is obtained . renewed detachment and pulling off of the guiding sleeve 78 from the third aiming wire 70 allows the guiding sleeve 78 to be turned once again by 90 °, as represented in fig2 by an arrow 85 . the third aiming wire 70 has then entered the third cannulation 88 ; the second aiming wire 68 lies in the first cannulation 84 . a fourth aiming wire 89 can then be set in the second guiding channel 82 , which has become free again . after removal of the device and overdrilling of the four aiming wires 32 , 68 , 70 and 89 , a drilled hole 90 with an approximately “ t ”- shaped profile , as represented in fig2 , then results in the bone 64 .
a device for preparing multiple channels in a bone comprises a handle , a single guiding sleeve mounted removable at said handle and an arm projected from said handle . said single guiding sleeve comprises a central first guiding channel for receiving a first aiming wire , a second guiding channel for receiving a further aiming wire , said channels have parallel axes . at least one cannulation is provided , a central longitudinal axis thereof runs at a distance and parallel to the guiding channels . said at least one cannulation being arranged offset in a circumferential direction to said second channel . an aiming wire introduced in said second channel can be replaced into a cannulation by pulling off the guiding sleeve turning it about the first aiming wire and reinserting the turned guiding sleeve into said handle .