Abstract: A device and a method for establishing a position and orientation for a preliminary saw cut in a distal end of a femur to prepare the femur for installation of a prosthetic knee joint. A guide block defining a cutting plane is carried on an adjustably positioned locating arm that is supported on an alignment body that can be mounted on a femur either with or without an intramedullary rod in place in the distal end of the femur. Adjustment screws and horizontal slots in the alignment body provide for varus/valgus angular adjustment of the position of the alignment body. An adjustment guide block may have a saw guiding face defining a differently oriented cutting plane.

Abstract: A medical device for preparing an elongated bone, such as a proximal femoral bone, for receiving an implant includes a patient-specific femoral guide and an elongated alignment element. The femoral guide has a patient-specific three-dimensional bone-engaging surface configured according to a preoperative plan based on a three-dimensional image model of the femoral bone to mate complementarily with the surface of the proximal femoral bone extending between the greater trochanter, the femoral neck and the femoral shaft of the proximal femur. The femoral guide includes a first guide end forming a planar guide configured for guiding a neck resection. The alignment member can be removably attached to the femoral guide and defines a reference axis for guiding a cutting tool into the femoral bone through a resected surface of the femoral neck.

Abstract: A guided reamer (10) has a central cannulation (12, 12a) adapted to receive a drill pin (14) secured in a manner which is axially aligned with the stem (22) of the bulbus bone joint (20). The reamer (10)has a profile cutting form (24) with cutting teeth (40) formed therein for cutting a form of a defined profile. The reamer (10) has a circumferential rim (34) having rim cutting teeth (36) disposed to cut to an outside of the rim and an inside of the rim, having face cutting teeth (37) adapted to cut an annular channel into bone and a plurality of planing teeth (52) radially disposed on an internal surface adjacent an axial end boss (44). The cannulation (12, 12a) is supported at the apex of the cutting form (24) and is formed in a guide assembly (70, 70?) affixed to the apex. The guide assembly (70, 70?) is adapted for imparting rotation to the reamer (12).

Abstract: A method of applying a femoral head resurfacing prosthesis to a selected femoral head includes mounting a jig on a femur corresponding to the selected femoral head. The jig includes an applicator adapted to engage the femoral head resurfacing prosthesis and push said prosthesis toward the femoral head without damaging an outer surface of the prosthesis. The jig is biased against the femur while moving the applicator from a first position in which the applicator is spaced from the head by a first distance to a second position in which the applicator is spaced from the head by a second distance shorter than said first distance thereby pushing the femoral head resurfacing prosthesis into position on the selected femoral head without damaging the outer surface of the prosthesis with the jig. The jig is removed from the femur once the resurfacing prosthesis is in position on the selected femoral head.

Abstract: In an embodiment, the methodology of the present invention is based on the use of an intraoperative navigation system and of a compact alignment guide for alignment of implant components. In an embodiment, an alignment guide of the present invention includes a first component fixable to a bone element; a second mobile component, and a third mobile component, wherein the second mobile component and two control mechanisms form a first link, wherein the two control mechanisms are working in parallel to perform adjustments in two degrees of freedom, wherein the third mobile component and three control mechanisms form a second link, wherein the three control mechanisms are working in parallel to perform adjustments in three additional degrees of freedom, and wherein the first link adjustments and the second link adjustments are performed in series to provide a total adjustment of five degrees of freedom relative to the first component.

Abstract: A system and method may be used for accessing an articular surface and for preparing an implant site on the articular surface. The method may include locating a portion of the articular. An access passage may be drilled towards the articular surface though bone behind the articular surface. An implant site may be excised in the articular surface relative to an axis defined by the access passage.

Abstract: Methods and devices for performing hip replacement surgery are described. According to one embodiment, a method comprising providing an incision locator, the incision locator comprising at least one location indicator and at least one incision indicator, the location indicator configured to align with a central axis of the femur, and the incision indicator configured to guide a proper placement of a surgical incision when the location indicator is aligned, aligning the location indicator with at least one anatomical feature of the patient, making an incision in the proper location as guided by the incision indicator, and completing the surgical procedure is described.

Abstract: A femoral head center locating mechanism and method for using same. The femoral head center locating mechanism may include a frame and a plurality of lasers which emit laser beams which intersect to identify a reference point relative to a center of a femoral head.

Abstract: A system for harvesting an implantable graft from the femur of a human having a cartilage overlying a condyle, according to which an overlay extends over the femur and is positioned relative to the femur by an articulating arm assembly.

Abstract: A total knee prosthesis comprises a femoral component and a patellar component. The femoral component has a patellar flange into which is built a twist or roller coaster configuration. The patellar component has an off-set dome with respective lateral and medial facets. The configuration of the patellar flange resists forces from a medial to a lateral direction, whilst the lateral and medial facets of the patellar component are respectively shaped to allow area contact and line contact respectively with the femoral component. Also disclosed is a device for intra-operative checking of patellar tracking to allow correct insertion of the femoral and patellar components.

Abstract: Surgical guiding tools for surgery on a bone head which include a cutting component, a guiding component and a collar having a patient-specific component are disclosed. The surgical guiding tools are interconnected which ensures secure and accurate placement of the guiding tool and thus guarantees accurate implementation of the pre-operative planning of the surgical intervention.

Abstract: Methods and apparatus for performing knee arthroplasty, including, but not limited to, bicruciate retaining knee arthroplasty, are described herein. Methods and apparatus for preparing a distal femur for a femoral implant as well as methods and apparatus for preparing a proximal tibia for a tibial implant are described. These methods and apparatus, in at least some embodiments and uses, facilitate decreasing the complexity of knee arthroplasty procedures such as bicruciate retaining procedures, while maintaining, if not improving on, the safety, accuracy and/or effectiveness of such procedures.

Abstract: A sizing caliper for determining the optimum size of a femoral component of a knee prosthesis includes a caliper body, a drill guide body, a stylus tower and a graduated stylus slidably coupled to the stylus tower. The caliper body, the drill guide body and the stylus tower are slidably linked to each other by a linkage pin laterally extending there through in a manner thereby when the caliper body and the stylus tower are linearly displaced in opposite directions in reference to the drill guide body, the caliper body and the stylus tower are linearly displaced at an equal rate with respect to the drill guide body.

Abstract: The present invention relates to a tool attachment for medical applications, comprising: a connecting section which is at rest relative to the part of the bone while the part of the bone is being machined; at least one machining section for machining a part of the bone; a fastening facility for fastening the tool attachment to a control device, wherein the connecting section is designed to connect the tool attachment, such that it is stationary, to a tool attachment guide.

Abstract: A femoral condyle cutting and shaping device includes a first bone shaping and cutting tool and at least one assistant shaft which are mounted in a sliding gearbox; at least one driven shaft mounted in a sliding gearbox; a first connecting member and a second connecting member, with one end of the first connecting member joining with one end of the second connecting member so as to form a hinge fitting; at least one other bone shaping and cutting tool mounted on the relevant driven shaft; an adjusting mechanism, which is connected with one driven shaft to change the relative position between the first bone shaping and cutting tool and the at least one other bone shaping and cutting tool. A bone shaping and cutting tool is also disclosed, which has flat or helical structure.

Abstract: An alignment guide for aligning instrumentation along a proximal femur includes a neck portion configured to wrap around a portion of the neck of the femur, a head underside portion configured to abut a disto-lateral portion of the femoral head and a medial head portion configured to overlie a medial portion of the head. Portions of the guide can have an inner surface generally a negative of the femoral bone of a specific patient that the guide overlies; such surfaces can be formed using data obtained from the specific patient. The neck portion can be configured to rotationally stabilize the guide by abutting and generating a first gripping force on the neck. The femoral head portions can be configured to grip the head portion of the femur and can support a bore guide that is configured to guide an instrument to the femur in a specified location and along a given axis.

Abstract: A hip stem centralizer datum guide and method are provided for positioning a proximal portion of a hip stem component within bone cement in an intramedullary canal of a femur. The datum guide is positionable in a predetermined position relative to the intramedullary canal and is able to create a datum that records the predetermined hip stem component position relative to the intramedullary canal. The datum is able to be referenced to position the hip stem component in the predetermined hip stem component position in the bone cement in the intramedullary canal.

Abstract: A device for indicating the location of the anteroposterior femoral axis has a spike or needle that engages the anterior-most point in the intercondylar notch and a rounded or spherical surface is placed on the trochlear groove of the femur and urged in a posterior direction. That is, the rounded surface or ball is urged toward the bottom of the trochlear groove. This causes the rounded surface or ball to self-locate into the deepest point of the trochlear groove. The anterior-most point in the intercondylar notch and the deepest part of the trochlear groove anteriorly are points that accurately determine the anteroposterior femoral axis, and the device includes a marking device or guide member that is fixed perpendicular to this axis. A surgeon, therefore, has an accurate indication of the correct femoral component rotation for proper implant position in a knee replacement or other surgical procedure.

Abstract: A system for modeling the pelvic anatomy of a person comprises an apparatus and method for using the apparatus. The apparatus includes a support and a sizing assembly. The support comprises a base and upstanding member. The sizing assembly is movable along the upstanding member to various heights. The sizing assembly includes a pubis stop arm with a pubis stop, and a pelvic seat arm. The pelvic seat arm supports a pair of opposed ischial seats. The pubis arm extends generally horizontally from the upstanding member. The pelvic seat arm has a horizontal ledge for receiving a patient's ischial tuberosity and an adjoining vertical wall for receiving a patient's medial aspect of the ischial ramus. The distance between the pubis stop and pelvic seats is adjustable, the distance between the pelvic seats is adjustable, and the relative angle between the vertical arms of the pelvic seat is adjustable to accommodate for different anatomies.

Abstract: Systems and methods are provided for navigated placement of bone engaging elements, such as support pins used to support a cutting block on a bone for resection. In one embodiment, a guide apparatus is configured to be mounted to a bone and provides multi-degree of freedom gross and fine adjustments of a pin guide. The pin guide carries a position tracking element so that its real-time spatial position relative to a location on the bone can be evaluated.

Abstract: The present invention relates to systems and methods for preparing the trochlear groove of a patient's femur to receive a prosthesis thereon. In the system, a combination drill-and-alignment guide includes at least a proximal and intermediate section, and preferably also includes a distal section. Guide holes for receiving guide pins therein are located in the proximal and distal sections of the guide. After the guide is positioned using at least one of several visual and/or tactile references in the system, the guides pins are placed through the guide holes of the guide and into bone. The guide may then be removed and replaced by cannulated reamers that are rotated and used to resect a predetermined amount of bone around the guide pins. A prosthesis having at least a portion of an outer surface that substantially matches the trochlear groove of the patient in a pre-degenerated state is then implanted on the resected bone.

Abstract: An apparatus and method are provided for aligning an extramedullary femoral cut guide by referencing the anterior cortex of a femur. An anterior cortex referencing extramedullary femoral cut guide is provided to guide an osteotomy device to prepare the femur to receive a prosthesis. An alignment gauge is included in the cut guide to determine proper and improper alignment of the cut guide with respect to the anterior cortex of the femur.

Abstract: The present invention relates to systems and methods for preparing the trochlear groove of a patient's femur to receive a prosthesis thereon. In the system, a combination drill-and-alignment guide includes at least a proximal and intermediate section, and preferably also includes a distal section. Guide holes for receiving guide pins therein are located in the proximal and distal sections of the guide. After the guide is positioned using at least one of several visual and/or tactile references in the system, the guides pins are placed through the guide holes of the guide and into bone. The guide may then be removed and replaced by cannulated reamers that are rotated and used to resect a predetermined amount of bone around the guide pins. A prosthesis having at least a portion of an outer surface that substantially matches the trochlear groove of the patient in a pre-degenerated state is then implanted on the resected bone.

Abstract: An instrument for controlling the distribution of bone cement on the surface of the head of a bone to prepare the bone to receive a re-surfacing prosthesis comprises a hollow shell which can be fitted on to the head of the bone to define a space around the head. The shell is rotationally symmetrical and has a spike like projection extending axially from the internal surface of the shell. At least one rib is located on the internal surface of the shell, extending from the spike like projection or from close to it, towards the open face of the shell, which contacts cement on the head of the bone in a sweeping action when the shell is rotated around its axis on the head of the bone.

Abstract: A femoral adjustment device to balance a flexion gap. The device includes a body attachable to a distal femur, the body having a cutting guide and an adjustment mechanism operable to balance the flexion gap, wherein upon balancing the flexion gap, the cutting guide is operable to guide at least one cut in the distal femur.

Abstract: A method for forming a tunnel in a bone. The method includes forming a first tunnel in the bone, the tunnel having a longitudinal axis, inserting a first drill guide into the first tunnel, supporting a first tunnel-forming device along an axis defining a first offset relative the longitudinal axis of the first tunnel with the first drill guide, and forming a second tunnel alongside the first tunnel with the first tunnel-forming device, the second tunnel communicating with the first tunnel and defining a single elongated opening.

Abstract: A precision adjustable surgical tool holder/driver is provided which is easily disassembled for cleaning and precisely reassembled. The holder/driver has a positionable handle allowing adjustment of the position of the handle about the spindle of the holder to enable the “handedness” of the holder to be changed in order to accommodate a user while operating from the left or right side of the patient, standing behind or in-front of the patient, or for use in different surgical methods. The holder/driver includes a “limited-play” capture mechanism, which connects the drive end of the housing to its locking sleeve via a limited-play locking device. The limited-play locking device utilizes a disengageable, precision fitted bayonet pin and seat combination in part to accomplish the precision reassembly feature of the present invention.

Abstract: An instrument system for setting the internal-external rotation of a prosthetic femoral component with respect to a proximal tibia has a bone resection instrument having a planar surface for engaging a planar surface of a resected distal femur. The bone resection instrument system has a cutting guide for guiding a tool for resecting a posterior surface of the distal femur and forming a cylindrical surface on the posterior condyle intersecting the planar surface. The cylindrical surface defined by an axis extending in a direction generally perpendicular to the resected planar surface. The system includes a trial component having a planar surface for engaging the planar surface of the resected distal femur and having posterior condyles having a cylindrical anteriorly facing surface engagable with the resected cylindrical surface on the posterior condyle.

Abstract: Disclosed herein are unicompartmental femoral and tibial arthroplasty jigs for respectively assisting in the performance of unicompartmental femoral and tibial arthroplasty procedures on femoral and tibial arthroplasty target regions. The femoral and tibial unicompartmental arthroplasty jigs each include a first side, a second side and a mating surface. Each second side is generally opposite its respective first side. For the femoral jig, the mating surface is in the first side of the femoral jig and configured to matingly receive and contact a generally planar area of an anterior side of a femoral shaft generally proximal of the patellar facet boarder and generally distal an articularis genu. The first side of the femoral jig is configured to be oriented towards the femoral arthroplasty target region surface when the mating surface of the femoral jig matingly receives and contacts the planar area.

Abstract: There is described a jig for identifying a point on the femoral head which is in alignment with a central axis of the femoral neck. The jig comprises a first member which defines a plane and has means for at least partially receiving the femoral neck. The jig also comprises a guide member which is mounted apart from the first member and which defines an axis at right angles to the plane defined by the first member. The axis of the guide member intersects the plane at a point which is a predetermined distance away from the means receiving the femoral neck. In addition, the jig comprises an elongate alignment means which is mounted with respect to the first member and which is spaced apart from, but extends parallel to, the axis of the guide member. There is also described a kit for use in the resurfacing of the femoral head. The kit comprises at least one jig as previously described.

Abstract: A jig for resurfacing the head of a femur comprises a centering guide defining a centering axis. It further comprises: a support suitable for fitting on a head of the femur and defining an envelope surface forming a portion of a sphere, the centering guide being fastened to the support with the centering axis aligned on a diameter of the sphere; and at least one abutment arm for coming into abutment against a predefined portion of a neck of the femur, the abutment arm being connected to the support and having a distal end that bears against the corresponding predefined portion when the support is fitted on the head of the femur with the centering axis aligned on the central axis of the neck of the femur or with a small amount of valgus.

Abstract: A jig and a system for supporting artificial hip joint with which an artificial shelf can be arranged at an ideal arranging position more easily at reduced facility cost. Since existing arthroscope (3) and a medical drill generally used in an operating room are fixed to and held on a small jig (4) for supporting artificial hip joint replacement of simple arrangement which can be fixed to the shell of a patient, correct profile of the shell HC of the patient at current moment in time can be recognized easily and surely with an arthroscope (3). Furthermore, since drilling position and direction of the medical drill can be determined using a first two-dimensional coordinates and a second two-dimensional coordinates, the shell HC of the patient can be shaped into ideal profile accurately without using an expensive special device for exclusive use and thereby the artificial shell can be arranged at an ideal position more easily.

Abstract: A bone fixation system including a bone plate and surgical drill guide is provided. The drill guide assembly includes one or more alignment drill tubes that are remotely aligned with corresponding fastener holes in the bone plate, and a plate holder to engage a hole in the bone plate. The surgical drill guide is releasably lockable to the plate holder.

Abstract: A method of reducing hair growth includes topical application of a TRPM8 and/or a TRPA1 agonist, alone or in conjunction with heat.

Abstract: A method of resecting a distal femur is disclosed. The method includes attaching a first block to the distal femur, the first block having a first surface providing a guiding surface for making an anterior chamfer cut on the femur, and a second surface providing a guiding surface for making a posterior chamfer cut on the femur, and making anterior and posterior chamfer cuts on the distal femur. The method further includes attaching a second block to the first block, the second block having a first surface providing a guiding surface for making an anterior cut on the femur, and a second surface providing a guiding surface for making a posterior cut on the femur, and making anterior and posterior cuts on the distal femur.

Abstract: A femoral neck fixation prosthesis and method of using same which reduces bone loss and the avoids the other shortcomings of the prior art by allowing the fixation of a stable femoral head replacement while reducing the amount of the femur which must be reamed for the insertion of the prosthesis. The preferred embodiment provides that the femoral head is attached to a fixation prosthesis, which extends coaxially through the canal of the femoral neck, into the femur, and is then attached to the opposite lateral wall of the femur. In this manner, the prosthesis serves to imitate the original structure of the femoral neck. No other support members, either crosspins or arms extending into the length of the femur, are required.

Abstract: A guide clamp for clamping a femur and guiding placement of a guide wire relative to the femur. The guide clamp includes a body supporting a pair of clamping surfaces at the end of a pair of clamping arms that are spring-biased to move with respect to each other into a closed position to grip the femur. Defined by the body is a guide opening that guides insertion of the guide pin once the femur has been gripped. One of the clamping arms of the guide clamp may have proximal and distal portions that are slidably adjustable with respect to each other to allow a controlled repositioning of the guide opening with respect to the femur. The guide clamp may also include an engagement member which is supported by the body of the clamp and is capable of advancing into abutting contact with the head of the femur.

Abstract: A device and method for resecting a distal portion of a femur comprises a distal cutting guide [98], a valgus guide [102], and a variable collet [10]. The distal cutting guide [98] is configured to overlie an anterior portion of the femur and comprises a slot for guiding a cutting tool across a distal portion of the femur. The valgus guide [102] is configured to connect to the distal cutting guide [98]. The valgus guide [102] is configured to align the slot of the distal cutting guide[98] at the proper varus/valgus angle. The variable collet [10] is configured to attach to an intramedullary rod and the valgus guide [102]. The variable collet [10] comprises a port [30] for receiving the intramedullary rod. The port [30] is angularly adjustable with respect to the valgus guide [102] such that adjusting the port [30] adjusts the varus/valgus angle of the distal cutting guide [98].

Abstract: A femoral sizer. The femoral sizer includes a stylus arm, and a stylus finger coupled to the stylus arm and movable relative to the stylus arm between a first configuration for insertion under soft tissue of a femur and a second configuration for sizing the femur.

Abstract: An acetabular impactor aids a surgeon in controlling the installation of an acetabular cup prosthesis having a central, female aperture. The impactor includes an impactor head, housing and a locking mechanism. The housing is attached to the impactor head, the housing enclosing a drive train having, at a far end, a prosthesis engaging thread, and at the opposite end, a handle which facilitates turning of the drive train by the operator. The locking mechanism is associated with the housing which selectively locks the drive train, and thus the prosthesis, in position. The opposite end of the drive train has a latch device which enables quick removal from the housing for cleaning and sterilization.

Abstract: A method of preparing a knee joint for receiving a unicondylar knee implant includes preparing a first seating surface at a proximal end of a tibia, and providing a combination bur template and spacer block, the bur template having an upper end, a lower end and a curved surface extending between the upper and lower ends thereof that is adapted to conform to a femoral condyle of a femur and the spacer block extending from the lower end of the bur template and having top and bottom surfaces. The method includes flexing the knee joint so that the prepared first seating surface at the proximal end of the tibia opposes a posterior region of the femoral condyle and inserting the combination bur template and spacer block into the knee joint so that the top surface of the spacer block engages the posterior region of the femoral condyle and the bottom surface of the spacer block engages the first seating surface at the proximal end of the tibia.

Abstract: A cutting block having a base, and a top connected to the base via four walls is disclosed. Each wall has an outwardly facing surface to guide a cutting tool. Each wall also has an attachment hole where a tracker may be attached. The cutting block is floated on the bone using the navigation system to position it at correct locations for the bone resection. After correctly locating the cutting block for each required cut, cutting block is fixed to the bone using pins and the bone resected. Same cutting block is suitable for resection of bone for installation of any size prosthetic device. For certain resections, the rotation angle may be mechanically set and need not be navigated.

Abstract: A guide for positioning a femoral tunnel during an ACL repair. The device may include a shaft having a lumen, the lumen defining a longitudinal axis, and a distal offset projection, at least a portion of the distal offset projection extending distally from the elongated shaft, wherein the distal offset projection and the shaft are moveable relative to each other.

Abstract: A guide for positioning a femoral tunnel during an ACL repair. The device may include a shaft having a distal end and a femoral surface engagement member. The femoral surface engagement member may be selectively deployable relative to the distal end of the shaft. The femoral surface engagement member may have a relatively sharp distal end, that is configured to alter, e.g., pierce, a surface of the femur.

Abstract: A device for positioning a femoral tunnel during ACL reconstruction, the device comprising: a shaft having a lumen, the lumen defining a longitudinal axis; and a distal offset projection, at least a portion of the distal offset projection extending distally from the elongated shaft; and a single lateral reference member configured to reference a portion of a patient's anatomy, e.g., a PCL or a portion of the femoral notch, the lateral reference member located on one of the left or the right side of the device, wherein, on a second one of the left or the right side of the device, the device defines a void. Two devices may be employed to provide a set.

Abstract: A guide for positioning a femoral tunnel during an ACL repair. The device may include a shaft having two or more lumen extending longitudinally therethrough. The device may also include a distal offset projection, at least a portion of the distal offset projection extending distally from the elongated shaft.

Abstract: A method and instrumentation for performing a patellofemoral arthroplasty orthopaedic procedure includes coupling an anterior cutting block to a femur of a patient such that the cutting block references local anatomy of the femur. The anterior cutting block is used to perform a number of bone cuts to establish a trochlear cavity in the femur. The trochlear cavity is formed such that a trochlear prosthesis may be inset into the cavity and substantially flush with the surrounding cartilage. A finishing burring guide and burr bit may be used to detail the shape and/or size of the trochlear cavity. Additionally, a trochlear drill guide may be used to facilitate establishing peg holes in the patient's femur to receive corresponding pegs of the trochlear prosthesis.

Abstract: A multi-positionable cut guide including a bone attachment device, base, and guide member. Bone attachment device is adapted to be coupled to the bone and has a base receiving portion. Base includes a mounting portion slideably coupled to base receiving portion such that base is slideable relative to attachment device along at least one dimension. Guide housing is pivotally mounted to base and guide member is rotatably mounted to guide housing. Guide member defines an axis about which it is rotatable. Guide member defines an elongated guide slot extending along the axis and adapted to receive and guide a saw for resecting the end of the bone. Guide slot defines a cut guide plane, the position of which is adjustable relative to the bone via sliding of base along at least one dimension, pivoting of the guide housing relative to base, and rotation of guide member about the axis.

Abstract: Tools for resecting the femur include an anchoring device, a three-way alignment guide and a six way alignment guide attachable to the anchoring device, a resection guide attachable to the three-way alignment guide and equipped with couplings for trackers, an A-P sizer, a femoral sizing block bushing attachable to the six-way alignment guide, a 4-in-i femoral cutting block, a 5-in-i positional alignment guide attachable to the six-way alignment guide, a pair of diodes, and a 5-in-one cutting block. Methods of utilizing the apparatus are also disclosed.

Abstract: The present invention relates to a femoral condyle cutting and shaping center (10), which comprises a main driving shaft (15) provided in a transmission gearbox (4), and a main driving gear (14) mounted on the main driving shaft (15). At least a first driven gear (12) is engaged with the main driving gear (14), said first driven gear (12) being mounted on a first driven shaft (13), said first driven shaft (13) being supported in the transmission gearbox (4). One end of the first driven shaft (13) extends towards the outside of the transmission gearbox (4), and a bone shaping mill (21) is mounted on an extending end (22) of the first driven shaft (13).