Abstract: An insertion instrument comprising an elongate shaft, a suction head provided at the front end thereof for connection to a joint socket, a suction device with a piston guided in the shaft, a suction line opening out at the suction head, and an actuating element which is guided along a guiding track on the shaft. The guiding track can be helically shaped and have a locking arrangement, preferably in the form of a recess, for the actuating element in a suction position. Due to the helical shape of the guiding track, the actuating element executes a rotational and longitudinal movement during its displacement. The longitudinal movement produces a negative pressure in the suction line ensuring maintenance of the pressure, while the rotating movement causes rotation of the actuating element such that it reaches its locking position at the end of the guiding track, providing simplified handling of the instrument.

Abstract: The present invention relates to surgical instruments and methods for the manufacture thereof, for facilitating the positioning of an implant in a socket of a ball-and-socket joint, by positioning an alignment element such as a pin, wire, screw or drill.

Abstract: An instrument for establishing orientation of a pelvic prosthesis comprises a tripod having an angularly adjustable guide rod on it. The tips of the legs define a plane, and the guide rod is set by the surgeon to a defined orientation with respect to this plane on the basis of preoperative studies. In use, two of the legs of the instrument are positioned by the surgeon at defined anatomical locations on the pelvis (e.g., a point in the region of the posterior/inferior acetabulum and a point on the anterior superior iliac spine). The third leg then lands on the pelvis at a point determined by the position of the first two points, as well as by the separations between the third leg and the other two legs. The position of the guide rod then defines with respect to the actual pelvis the direction for insertion of a prosthesis.

Abstract: An alignment guide is described that includes a shaft having a longitudinal axis and a housing attachable to the shaft and rotatable about a first axis that is substantially perpendicular to the longitudinal axis. A guide arm the extends from the housing at a predetermined angle along a second axis. A spirit level is connected to the housing on a plane aligned with the predetermined angle.

Abstract: A surgical instrument for implanting a prosthetic member. The instrument includes an orientation sensor that detects an initial orientation of the prosthetic member and an implanting orientation of the prosthetic member. The instrument further includes a memory module and an input device that receives a user input to transfer the initial orientation detected by the orientation sensor into the memory module for storage. Furthermore, the instrument includes an orientation feedback device that selectively provides an orientation feedback signal to a user. Moreover, the instrument includes a controller that causes the orientation feedback device to provide the orientation feedback signal when the implanting orientation detected by the orientation sensor is substantially equal to the initial orientation stored in the memory module.

Abstract: Methods, systems, and apparatus, including computer-readable storage media, for surgical alignment using references. In one general aspect, a method includes coupling a guide to a joint, the guide defining an axis and having an outer contour formed to substantially conform to a portion of the joint. The first reference is attached at a fixed position relative to the joint. A positioning system is used to determine a position of the axis relative to the first reference, where the position of the axis is determined based upon the position of the guide while the guide is coupled to the joint. The guide is removed from the joint, and after the guide is removed from the joint, an instrument is positioned relative to the axis based on a position of a second reference relative to the first reference.

Abstract: An instrument for positioning a cup component of an orthopaedic joint prosthesis includes a shaft, a housing attached to the distal end of the shaft, at least two flange portions carried on the shaft on which the cup component can be fixed, and a unitary spring element disposed about the shaft axis and disposed between the at least two flange portions and the axis of the shaft. The housing includes a base plate and extends from the shaft transversely relative to the shaft axis. The at least two flange portions can move relative to the base plate in a direction transverse to the shaft axis between an in-use position, where at least a portion of each of the at least two flange portions contacts the inner surface of the cup component, and a retracted position where the at least a portion of each of the at least two flange portions is moved towards the shaft axis so as to allow the cup component to be released from the instrument.

Abstract: An adapter for a crossbar surgical reamer having a base with an interface for connecting with another style of reamer such as a crossbar reamer. Intersecting axially facing recesses are provided on the end of the base for connection with a crossbar type of reamer. A pair of grips are pivotally mounted on the base and urged to a closed position by a cross spring to releasably hold the crossbar reamer within the recesses for installation and removal substantially in an axial direction.

Abstract: The invention relates to guiding instruments (1) for guiding an acetabular cup implant as well as to impactors (13) for press-fitting an acetabular cup implant, both of which are of use during reconstructive joint surgery, more specifically during reconstructive hip joint surgery. The guiding instruments are characterized in that they fit onto an acetabular cup implant (8) and are designed to fit onto specific areas of the pelvic bone ensuring a unique fit on the bone. The impactors are characterized in that a fixation element (15) is connected to the stem (14) of the impactor by a ball joint. The invention also relates to combined guiding and fitting elements for an acetabular cup implant, comprising a guiding instrument and an impactor.

Abstract: Orthopedic systems and methods are provided for use in preparing joints for implants. Specifically, hip preparation systems and methods are disclosed which can include a surgical orientation device. The hip preparation systems and methods can be used, for example, to orient the hip during the procedure, determine the orientation of an anatomical plane or planes, and orient a prosthetic component or components.

Abstract: A system for assisting in a surgical process, comprising: (a) a surgical device taken from a group consisting of a surgical tool and a surgical implant; (b) a positional sensor carried by the surgical device, the positional sensor including a wireless transmitter and associated circuitry for transmitting sensor data from the transmitter; and (c) a computer system including a wireless receiver and signal conditioning circuitry and hardware for converting sensor data received by the wireless receiver into at least one of (i) audio feedback of positional information for the surgical device and (ii) visual feedback of positional information for the surgical device.

Abstract: A surgical device for holding and rotating an acetabular reaming head is provided, comprising a shaft having a length which runs from a first end adapted for holding an acetabular reaming head to a second end. At least part of the shaft is divergent from the axis defined by the first and second ends of the shaft, for example the shaft may include a C-shaped divergent portion. A head held by the device can therefore access the acetabular in its true anatomical position while avoiding encroachment of the shaft on surrounding body parts.

Abstract: An orthopedic prosthetic inserter used for the implantation of an acetabular prosthetic cup implant. The inserter consists of a drive train, a C-shaped housing, and a collet mechanism used to attach a prosthetic cup implant. When activated by the drive train, the collet mechanism expands to draw the prosthesis towards the collet mechanism and create a substantially friction tight engagement therebetween.

Abstract: The present application relates to a system for navigation-assisted shoulder operations in which the humeral component is partially replaced with a prosthesis, comprising: a first tracking unit which is configured to be fastened to a section of a bone which is to be removed during the operation; a detection unit which is configured to detect landmarks on the bone; a second tracking unit which is configured to be attached to another section of the same bone; a camera unit which simultaneously detects the first and second tracking unit, in order to determine their respective location; and a computational unit which is connected to the camera unit and is configured to: determine a first relative location of the landmarks relative to the first tracking unit from data acquired by means of the detection unit; and calculate a second relative location of the landmarks relative to the second tracking unit on the basis of the first relative location; such that additional navigated treatment apparatuses can be exac

Abstract: A method of determining the pedicle base circumference and the pedicle isthmus to facilitate screw placement in a pedicle of a vertebral body during spinal surgery, comprising providing a series of first lines tangential to the outer cortical surface of the vertebral body in and near the pedicle on a transverse section from a three-dimensional image of the vertebral body, providing a series of second lines extending through the vertebral body in and near the pedicle thereof in perpendicular relation to the series of first lines, identifying the pedicle base circumference as the areas of the outer cortical surface where adjacent second lines are at the greatest angle with respect to one another, and identifying the pedicle isthmus as the areas of the outer cortical surface where the second lines that are opposed to each other are closest to being parallel to one another.

Abstract: A pre-assembled orthopaedic implant adapted for improved gas sterilization. The implant includes a first component adapted for assembly with a second component such that a mating surface of the first component is in close proximity with a mating surface of the second component. At least one gas conduit associated with the mating surface of the first component facilitates a sterilizing gas to penetrate into and dissipate from the interface defined by the mating surfaces.

Abstract: Provided is a preoperatively designed guidance tool for intraoperative use during acetabular cup replacement surgery, comprising: a patient-specific template having at least one surface that registers with a selected surface of the patient's acetabulum; and a guide portion that provides an orientation or a position and orientation of an acetabular cup according to a preoperatively planned orientation or position and orientation. The guidance tool may further comprise a verification tool that cooperates with the guide portion and includes at least one mating surface that registers with a selected surface of the patient's anatomy, wherein correct positioning of the verification tool on the patient's anatomy confirms correct orientation of the patient-specific template in the patient's acetabulum.

Abstract: An instrument for establishing orientation of a pelvic prosthesis comprises a tri-pod having an angularly adjustable guide rod on it. The tips of the legs define a plane, and the guide rod is set by the surgeon to a defined orientation with respect to this plane on the basis of preoperative studies. In use, two of the legs of the instrument are positioned by the surgeon at defined anatomical locations on the pelvis (e.g., a point in the region of the posterior/inferior acetabulum and a point on the anterior superior iliac spine). The third leg then lands on the pelvis at a point determined by the position of the first two points, as well as by the separations between the third leg and the other two legs. The separations are adjustable, but are preferably fixed percentages of the separation between the first and second legs. The position of the guide rod then defines with respect to the actual pelvis the direction for insertion of a prosthesis.

Abstract: A patient-specific acetabular guide can be used for preparing an acetabulum of a patient to receive an acetabular implant. The acetabular guide includes a patient-specific engagement surface designed to be complementary and mateable with a corresponding surface of the patient's pelvic anatomy. The acetabular guide is designed during a pre-operative plan for the patient by a three-dimensional reconstruction of the anatomy of the patient using two-dimensional medical images. The patient-specific engagement surface has a first portion mateable with a portion of the acetabulum of the patient. The acetabular guide includes a guiding element that extends from the acetabular guide opposite to the first portion of engagement surface. The guiding element defines a bore designed to be oriented along an alignment axis for an acetabular implant when the acetabular guide is engaged to the acetabulum.

Abstract: An expandable shoulder trial for a reverse shoulder system is described. The trial includes a rotatably adjustable insert housed within a humeral cup. The insert has a proximal end and a distal end, the proximal end having a concave recess therein adapted to receive a glenosphere prosthesis. The distal end of the insert includes a shaft, the shaft having a helical groove disposed on at least a portion thereof. A distal end of the humeral cup is inserted in a humeral stem. The humeral cup has a proximal end including a recess therein, the recess defined by a circular wall. A guide pin protrudes from the circular wall and is adapted to engage the helical groove of the shaft of the insert. The proximal end of the insert may rotate along an axis toward the proximal end of the humeral cup and along the same axis away from the proximal end of the humeral cup.

Abstract: A method for determining a depth of impaction of a prosthetic cup into an acetabulum using an end effector and a movable impactor shaft is provided, wherein the prosthetic cup may be positioned at a distal end of the impactor shaft. The method may position the distal end of the impactor shaft at a known pose relative to the end effector, track a spatial pose of the end effector relative to a spatial pose of the acetabulum, determine a spatial pose of the prosthetic cup based on the spatial pose of the end effector and the known pose between the distal end of the impactor shaft and the end effector, and determine the depth of impaction based on the spatial pose of the prosthetic cup and the spatial pose of the acetabulum.

Abstract: An adaptor/holder (40) is described which attaches to the front (18) of an existing orthopedic inserter/impactor handle (10) via the handle's existing threaded interface mechanism (22). The adaptor/holder (40) has an annular housing (42) that snaps onto the front (18) of the existing inserter (10), and has an internal yoke and pin assembly (70) that attached to the handle's interface mechanism (22). The holder (40) adapts the inserter (10) to much more easily and quickly release from a prosthetic component (12) after the component (12) is surgically implanted in a patient, and with less mechanical manipulation than could otherwise be accomplished using the inserter (10) alone. The adaptor/holder utilizes the inserter's existing mount tensioning (draw piston) mechanism (30) to quickly engage and disengage the prosthetic component (12). Upon activation of the inserter's tensioning mechanism (30), the holder (10) receives and fixes a prosthetic component (12) to the end (18) of the inserter (10).

Abstract: An acetabular inserter (10) aids a surgeon in controlling the installation of an acetabular cup prosthesis (11) having a central, female aperture (13). The inserter includes an inserter head (20), a housing (12) and a locking mechanism. The housing (12) is attached to the inserter head, the housing enclosing a drive train (14) having, at a far end (134), a prosthesis engaging thread (124), and at the opposite end (42?), a handle (20) 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 (42?) of the drive train has a latch device which enables quick removal from the housing for cleaning and sterilization.

Abstract: A surgical tool device for effecting implantation of an implant such as an acetabular cup during a hip replacement surgery is described. The surgical tool holder has a strike plate, a body, a proximal fixed handle, a distal rotate handle, an insert handle with threads, an impactor head, a shaft, the shaft pin, a shaft ring, and a spring. In use, when a surgical implant device is threaded onto the shaft, the surgeon merely rotates the assembly comprising the distal rotate handle and the insert handle with threads in one direction, which causes a distal threaded area of the shaft to rotate in a second, opposite direction to act as a lock-nut for the surgical implant. This movement simultaneously pulls the shaft toward the surgical tool holder proximal end. The pulling motion ensures the surgical implant device is positioned against the impactor head's contacting surface to provide a rigid assembly for good tactile feel during the implantation of the cup.

Abstract: The present disclosure provides an improved osteotome instrument for removing an acetabular cup from an acetabulum, including an explant adapter connectable to an elongated handle shaft of the instrument. The explant adapter is sized and shaped to connect any one of a set of a plurality of different sized interchangeable pivot elements, such as spherical heads, to the osteotome instrument for use in removing the acetabular cup from the acetabulum. The pivot heads may be relatively large diameter pivot heads.

Abstract: An acetabular component alignment device for total hip arthroplasty comprises a calibration component (9) allowing for aligning a main instrument axis (5) of the acetabular component depending on a set of two patient specific calibration parameters relating to rotational offsets of the acetabular component, whereas the device is constructed in such a way that calibration parameters may be chosen such that a second parameter of the set of calibration parameters is adjustable independently from a first parameter of the set of calibration parameters by rotating the acetabular component around the main instrument axis (5) of the acetabular component.

Abstract: A cap for use during the insertion of a prosthesis comprising: an impaction plate; an least one cable loop for connecting the impaction plate to a prosthesis; clamping means for attaching the at least one cable means to the impaction plate; and cutting means for severing the at least one loop at one point along its length.

Abstract: A prosthetic acetabular cup inserter and impactor has a body, and a cup engaging element disposed at a first end of the body and adapted to engage an inner surface of a cup with which it is used via outward biasing of the cup engaging element. The cup engaging element increases in cross-sectional area from an inner end thereof to a fullest transverse section, and decreases in cross-sectional area from said fullest transverse section to an outer end thereof. The cup engaging element has a tapered central bore engaged by a conically tapered actuation element moveable in the bore. The cup engaging element has a slot therethrough allowing the element to resiliently expand on movement of the actuator in the bore.

Abstract: A prosthetic acetabular cup inserter and impactor has a body, a cup engaging element disposed at a first end of the body which is adapted to engage an inner surface of a cup with which it is used. An operating system is adapted to axially rotate the cup engaging element in relation to the body in use. An impaction plate that is adapted to engage an undulating rim of the cup is disposed between the body and the cup engaging element. The impaction plate is connected to the operating system by a linkage which acts to axially rotate the impaction plate in unison with the cup engaging element in use.

Abstract: A system and method for detecting and measuring changes in angular position with respect to a reference plane is useful in surgical procedures for orienting various instruments, prosthesis, and implants with respect to anatomical landmarks. One embodiment of the device uses dual orientation devices of a type capable of measuring angular position changes from a reference position. One such device provides information as to changes in position of an anatomical landmark relative to a reference position. The second device provides information as to changes in position of a surgical instrument and/or prosthesis relative to the reference position.

Abstract: The present disclosure relates to a guide. The guide includes a handle and a shaft coupled to the handle, the shaft including a lip located at a distance from the longitudinal axis of the shaft and extending a distance from an end of the shaft. A method of tissue repair is also disclosed.

Abstract: An alignment device comprises a guide having a tangible guide component, said guide being configured for arranging the guide component at an angle with respect to a reference element; and a positioning means; the positioning means and the guide component being operable to cooperate to position an item at the angle set by the guide component. The alignment device is particularly useful in surgical procedures for the alignment of surgical tools and implants.

Abstract: A method for inserting an acetabular cup into an acetabulum of a patient includes inspecting a preoperative plan including a three-dimensional image of a patient's acetabulum, selecting at least one of a patient-specific anteversion angle and a patient-specific abduction angle, and approving the preoperative plan. The method also includes preparing the patient's acetabulum for implantation, positioning a patient-specific first surface of an acetabular guide around a matched acetabular rim surface of the patient, and inserting an acetabular cup through an opening of the acetabular guide, the opening having a cylindrical inner surface oriented at the selected at least one of the patient-specific anteversion angle and patient-specific abduction angle.

Abstract: A surgical apparatus includes an orientation sensor that detects an actual orientation of a surgical tool. The apparatus also includes an orientation feedback device that selectively provides an orientation feedback signal. Moreover, the apparatus includes a controller that causes the orientation feedback device to provide the orientation feedback signal when the actual orientation of the surgical tool detected by the orientation sensor is substantially equal to a predetermined target orientation of the surgical tool.

Abstract: A trial head and shell for use in trial reduction of hip implants, and particularly bipolar implants, having locking features that prevent the head from dissociating from the shell during trialing, yet which allow the head and shell to be readily assembled and disassembled in the operating room. A cut-out region is formed in an outer bearing surface of the head. The cut-out region allows the head to pass through a trial shell opening and into the shell, yet is oriented such that when the head is associated with a femoral neck, the head cannot disassociate from the shell. Orientation indicators can be provided for use in assembly and disassembly. The trial head and associated shells can be provided in the form of a surgical kit including hip implants. Methods of use are provided.

Abstract: A method of connecting an impactor to an orthopaedic implant includes the steps of: providing the impactor including a shaft having a proximal end and a distal end, a trigger pivotably connected to the distal end, the trigger including a cam end, a push rod within the shaft and connected to the cam end of the trigger and a threaded pair connected to an end of the push rod opposite the trigger; providing the orthopaedic implant including a threaded hole; locating the threaded pair within the threaded hole; pivoting the trigger; linearly displacing the push rod; and radially expanding the threaded pair to engage the threaded hole.

Abstract: An acetabular system includes an acetabular guide having a first surface and a second surface opposite to the first surface, the first surface made to conform to an acetabular rim surface around an acetabulum of a patient in accordance with a three-dimensional image of the acetabulum of the patient. The acetabular guide includes an aperture having an inner surface oriented at selected anteversion and abduction angles relative to the first surface for guiding an acetabular implant into the acetabulum at the selected anteversion and abduction angles.

Abstract: A system and method for placing an implant into or onto supporting bone, or between adjacent bones, without impaction is disclosed. The system includes an implant, a distracter, and a sleeve. Optionally, the invention includes an alignment guide, a surgical navigational tracker, and a bone displacer. The sleeve is structured to interpose the implant and supporting bone and provide a differential engagement force between the sleeve-implant interface and the sleeve-bone interface to preferentially move the implant into, onto or between supporting bone structures.

Abstract: An orthopaedic prosthetic inserter used for the implantation of double mobility cup implants is described. The inserter consists of a drive train, a C-shaped housing, and a prosthetic cup engaging subassembly. The subassembly comprises an impaction plate, a grasping plate and a domed nose. When activated by the drive train, a plurality of hook ends extending from the grasping plate latch onto the cup of the prosthetic to hold and manipulate the prosthetic cup during implantation.

Abstract: An instrument for gripping a cup component of an orthopaedic joint prosthesis comprises a drive plate having a spiral track formed on it and at least two jaw members. Each of the jaw members has a formation on it which can engage the spiral track, and a guide in which the jaw member is a sliding fit. The formations on the jaw members cause the jaw members to translate in their respective guides when the drive plate is rotated.

Abstract: An instrument for preparing a cavity for a stem of a prosthetic implant for use in performing joint arthroplasty on a head of a long bone is provided. The instrument includes a body and a punch extending from the body. The punch includes a portion of the punch having a shape similar to the stem of the implant.

Abstract: Systems, devices, and methods are provided for orthopedic implants. The implants may include a base member, such as an acetabular shell or an augment, that is configured to couple with an augment, flange cup, mounting member, or any other suitable orthopedic attachment. An implant component may be expandable to allow for adjustment and custom fitting during implantation. An expandable implant may have a first portion and a second portion separated by a slit. An expansion member can be disposed between the first and second portions and can be actuated to displace the two portions relative to each other, increasing the size of the implant. Any number of slits and expandable sections can be included in the implant to provided more flexibility in the expansion of the implant.

Abstract: An expandable shoulder trial for a reverse shoulder system is described. The trial includes a rotatably adjustable insert housed within a humeral cup. The insert has a proximal end and a distal end, the proximal end having a concave recess therein adapted to receive a glenosphere prosthesis. The distal end of the insert includes a shaft, the shaft having a helical groove disposed on at least a portion thereof. A distal end of the humeral cup is inserted in a humeral stem. The humeral cup has a proximal end including a recess therein, the recess defined by a circular wall. A guide pin protrudes from the circular wall and is adapted to engage the helical groove of the shaft of the insert. The proximal end of the insert may rotate along an axis toward the proximal end of the humeral cup and along the same axis away from the proximal end of the humeral cup.

Abstract: Disclosed herein are systems and methods for performing total hip arthroplasty with patient-specific guides Pre-operative images of a pelvic region of a patient are taken in order to predefine the structure of the guides and corresponding implants. From the obtained image data an insertional vector for implanting an acetabular implant or component into an acetabulum of the patient is determined, wherein the insertional vector is coaxial with a polar axis of the acetabular component. Also from the obtained image data, a superior surface of the guides and implants can be shaped to match the acetabulum of the patient. A nub portion extending outwardly from the superior surface of the guides and implants is shaped to substantially match the shape of a fovea of the acetabulum. A guide portion of the guides forming a slot has a longitudinal axis coaxial with the determined insertional vector of a corresponding acetabular component.

Abstract: A system and method for detecting and measuring changes in angular position with respect to a reference plane is useful in surgical procedures for orienting various instruments, prosthesis, and implants with respect to anatomical landmarks. One embodiment of the device uses dual orientation devices of a type capable of measuring angular position changes from a reference position. One such device provides information as to changes in position of an anatomical landmark relative to a reference position. The second device provides information as to changes in position of a surgical instrument and/or prosthesis relative to the reference position.

Abstract: A method of aligning an alignment guide relative to a reamed acetabulum of a patient is provided. The method includes the step of manipulating an alignment guide comprising a shaft having a longitudinal axis and a guide arm having a first portion, a second portion and a third portion, the first portion attached to the shaft and configured to be rotatable about a first axis substantially perpendicular to the longitudinal axis, the second portion extending from the first portion at a first predetermined angle along a second axis, and the third portion extending from the second portion at a second predetermined angle. The guide arm is rotated about the first axis relative to the shaft. A cup or trial is attached to the distal end of the shaft and positioned to contact the reamed acetabulum. The third portion of the guide arm is then oriented with respect to the long axis of the patient and the surface of the table on which the patient is positioned.

Abstract: An acetabular reamer (10, 10?, 10?) is intended in particular for the shaping of the cotyloid cavity in the event of a replacement of a hip joint by total prosthesis. The reamer (10, 10?, 10?) is typically of a truncated hemispherical form and is adapted for attachment to a reamer spindle in order to be driven in rotation about a cutter axis (11). The ability to cut a full, continuous hemisphere to the apex (12) of the hemispherical body (14) is suppressed, so as to attain the principal advantage of the invention, namely, to adequately prepare the acetabulum for receipt of a prosthesis while minimizing the possibility of breakthrough of the fovea/acetabular fossa. The reamer (10, 10?, 10?) has an interface 16 typically made tip of cross bars (20) which a holder engages for rotationally activating the reamer for cutting.

Abstract: A hip cup extraction apparatus (101) comprising a shaft (402), a handle (404), a semicircular cutting blade (406), a spring loaded latching member (408), and a head (100) for removing a hip cup (405) from a pelvic bone (401). The head (100) includes a semispherical section (102) terminating in a substantially planar surface (104), a hip cup extraction apparatus aperture (106), a retaining sleeve (108), and a three sided void (110). The head (100) may be configured for selective attachment to the hip cup extraction apparatus (101). The hip cup extraction apparatus (101) is inserted into the hip cup extraction apparatus aperture (106), and an optional spring loaded latching member (408) retains the head (100) in place. As the head (100) is being attached to the hip cup extraction apparatus (101), the semicircular cutting blade (406) may pass through the three sided void (110). Once the head (100) is attached to the hip cup extraction apparatus (101), the head (100) is inserted into the hip cup (405).

Abstract: An acetabular shell or cup removal instrument is disclosed. The instrument includes a first end capable of being received within an acetabular cup and a cutting element pivotally attached. Cutting motion is provided to the instrument by a powered handpiece, so that the cutting element is capable of cutting a bone surface adjacent to an outer surface of the acetabular cup when the first end is within the acetabular cup.

Abstract: A cup for a hip replacement is disposed in a first relationship in an operating room with an object providing a sighting for the cup rotation in a first plane. The cup is thereafter rotated in the first plane through a first angle (e.g., 20°-30°). The cup is then disposed in a planar relationship in the operating room with another object providing a sighting for the cup rotation in a second plane transverse (e.g. perpendicular) to the first plane. The cup is subsequently rotated through a second angle (e.g. 40°-45°) in the second plane. In this way, the cup is properly positioned in the acetabulum socket. The length of the leg receiving the hip rotation is then adjusted so that the leg length matches the length of the patient's other leg. This adjustment is provided without affecting the offset position of the center of the ball on the femur.