Abstract: A torque-limiting driver (10) for orthopedic surgical use has a housing (16) to which a torque force may be applied and transferred to a driver output shaft (18). The housing (16) encloses a cam bearing assembly (52) having a ball cage (54) disposed so that balls (56) of the ball cage (54) moves along a first vector path (Vr) radial to the axis of rotation (20). The bearing assembly also has an inner race (58) abutting the ball (56) and which inner race (58) travels along a second vector path (F) parallel to the axis of rotation (20). The first vector path (Vr) and the second vector path (F) are not co-axial. A bearing load assembly (70) applies a bias force (F) to the inner race (58) of the cam bearing assembly (52) to set the calibrated maximum amount of torque that can be transmitted via the housing (16) through the cam bearing assembly (52) to output shaft (18) of the torque-limiting driver (10).

Abstract: An adjustable reamer spindle is provided to aid the surgeon in controlling the instrument. The reamer spindle is easily disassembled for cleaning. The spindle has a repositionable handle, a locking ring, and an elastic device. The elastic device biases against a handle locking mechanism that locks the repositionable handle at angular positions about an axis of the spindle. The elastic device further biases a locking ring into a locked position. The locking ring aids in holding the reamer spindle together. Removal of the locking ring against an elastic bias of the elastic means unfastens an end of the assembly in order to facilitate disassembly and/or cleaning. Adjustment of the position of the handle about the spindle enables the palm/grip of each hand to be changed in order to provide maximum control in different orientations.

Abstract: A bone plate (10) is described which is adapted for use in situ to fix a spatial relationship of at least two bone parts (80). The bone plate (10) has at least one pair of the bone screw apertures that are adjoined by a relief-space contiguous with the open space of the screw apertures themselves. An adjoined aperture pair forms a complex aperture and has a center-to-center distanced of the apertures along an axis running through the centers of the apertures. The center-to-center distance d is equal to or greater than the sum of the radii (r1+r2) of the heads of the individual bone screw used with the aperture pair. At least one of the screw apertures (24) has a screw head seat (34) having at least one relief notch (84) set into a surface of the screw head seat (34). The relief notch 84 provides desirable advantages that are not similarly accomplished in their absence, such as a clearance passage for a tensioning wire 88 or a receiver for a self-locking insert 92.

Abstract: A bone plate is described which is adapted for use in situ to fix a spatial relationship of at least two bone parts. The bone plate has at least one pair of the bone screw apertures that are adjoined by a relief-space contiguous with the open space of the screw apertures themselves. An adjoined aperture pair forms a complex aperture and has a center-to-center distance d of the apertures along an axis running through the centers of the apertures. The center-to-center distance d is equal to or greater than the sum of the radii (r1+r2) of the heads of the individual bone screw used with the aperture pair.

Abstract: A rotary surgical reamer assembly for removing bone and tissue from a joint to facilitate the installation of a prosthetic device. The assembly includes a hollow reamer body having an opening and a base portion. The base portion includes a first pivoting link member, a wall with a surface defining a central cavity, and a plurality of spaced apart cutting sites defining apertures through said wall. A shaft is configured to be de-mountably attached to a rotary source of power. The shaft has a rotary axis and a second pivoting link member coupled to the first pivoting link member. The axis of the shaft forms an angle to the base portion. A mechanism adjusts the angle of the hollow reamer body from an un-deployed position to a deployed position.

Abstract: A flexible torque-transmitting coupling assembly and method is disclosed, as well as flexible surgical reamers having such assemblies. The reamers employ a fitting with radially flexible member, e.g., a split collet or a super-elastic collar that receives an elongated tubular shaft of super-elastic alloy. A compression sleeve is applied to the collet, in one embodiment, while the collar is located within a counter-bore of the fitting in another embodiment. Relative motion between the shaft, fitting and collet (or collar) induces a super-elastic activation in the shaft to form the desired coupling.

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 bone plate(s) of complex form is provided, particularly suited to tibial plateau-leveling osteotomy and a distal femoral osteotomy. The bone plate has a main longitudinal axis, a bone-contacting bottom side (not shown) and a top side with at least three sets of overlapping holes which communicate through the plate from the top to the bottom side. The sets of overlapping holes define threaded apertures having multifaceted surfaces. When applied to a bone, two sets of such overlapping holes are located so as to lie on opposite sides of an osteotomy site and on the tibial plate; a third is aligned at approximately 60 degrees with the longitudinal axis. The configuration of this complex bone plate vary, depending on the physiology of the patient. An object of the invention is to provide an orthopaedic surgeon greater flexibility of choice in that a threaded peg providing secure fixing can be positioned at any interval along the bone plate, including at its extreme ends or on its elbow.

Abstract: An instrument holder (10) for surgical use has a remote locking mechanism (12) and is elongated having a proximal end (14) and a distal end (16). The holder (10) has an elongated shank (20), a ring (22), a locking component (28) and a spring (32). The elongated shank (20) is equipped, at the distal end (16), with a head (26) adapted to receive an instrument (24). The locking component (28) is substantially cylindrical, elongated and is biased in a first direction (30) toward the head (26) by a spring (32). The locking component (28) includes structures (34) capable of locking the instrument (24) onto the distal end (16). The ring (22) is biased by the spring (32) in a second direction (36) against the locking component (28) towards the proximal end (14) constrained to slide longitudinally on the shank (20), at the proximal end.

Abstract: A surgical instrument holder has a shank having a coupling end, a handle attached to an opposite end of the shank, a coupling device, and a locking mechanism. The coupling end has an interface thereon for receiving an instrument. The locking mechanism has an annular locking component, a spring, a ring which slides on the shank, and a locking device. The annular locking component is mounted so as to slide along the shank. The locking device cooperates with the locking component so as to lock the instrument onto the interface. The spring biases the locking component in a locking direction and bears on the ring. The ring is disengageably lockable to the shank via a connection device so as to enable quick disassembly for cleaning and component sterilization.

Abstract: A surgical tool holder comprises a shank having first driveable end and second coupling end, the second end comprising a coupling device having interfaces for mating with corresponding structures on the inside of a hollow surgical tool, a first interface mating with a centering structure near a base end of the tool and a second interface mating with a second structure adjacent to a forward end of the tool, the tool being held in functional assembly to the shank by a releasable locking mechanism comprised of a locking sleeve slideably disposed about the shank, a spring biased against the coupling device by the locking sleeve, and a connection device retaining the locking sleeve in a fixed position during use, whereupon release of the connection device enables quick disassembly of the locking sleeve, spring and coupling device for cleaning and component sterilization.

Abstract: Disclosed is a torque-transmitting coupling assembly and method, as well as flexible surgical reamers having such assemblies. The reamers employ a fitting with radially flexible member, e.g., a split collet or a super-elastic collar that receives an elongated tubular shaft of super-elastic alloy. A compression sleeve is applied to the collet, in one embodiment, while the collar is located within a counter-bore of the fitting in another embodiment. Relative motion between the shaft, fitting and collet (or collar) induces a super-elastic activation in the shaft to form the desired coupling.

Abstract: A modular tool connection assembly includes a housing which defines the main axis of assembly with a linear bore for containing the components of the assembly. The housing contains a connector component presenting a first taper portion. The connector is retained in the linear bore of the housing with a spring interposed between the connector and the housing. A tool containing a second taper portion is placed in axial engagement with the first taper causing the components to be securely connected. The spring limits the force applied between the taper portions allowing them to be disconnected easily.

Abstract: A surgical tool holder has a shank having a central axis, a first driveable end and second coupling end. The second end has a coupling device having interfaces each for mating with corresponding structures on the inside of a hollow reamer. The interfaces mate with centering structures at or near a base end of each tool, the tool being held in functional assembly to the shank by a releasable locking mechanism.

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: Instrument holder comprising a shank (1) equipped with a head (2) designed to receive an instrument and a locking component (4) pushed against the head by a spring (9) bearing on a ring (11) sliding on the shank, and having means of connection (8, 12) on the shank which is engaged by rotation of the ring, in such a way that the release of the ring allows the locking component, the spring and the ring to slide freely in order to permit cleaning of the instrument holder.

Abstract: An acetabular reamer (10?) for cutting a required cut shape. The reamer has a cutting shell (12?) having a series of doubly curved cutting teeth (16?) thereon of a quantity to substantially reduce a cutting pressure on each tooth as well as to reduce a size of a typical chip generated upon cutting. Substantially all the teeth each have a matched arc cutting edge (20?) of substantial length that has a cutting profile which substantially matches a profile of a shape to be cut. The apertures in which the cutting edges are formed has at least one flat edge by which a punch, used in the process of forming the edge may be oriented. Such a configuration reduces the number of teeth required to cut the shape.

Abstract: An adjustable reamer spindle is provided to aid the surgeon in controlling the instrument. The reamer spindle is easily disassembled for cleaning. The spindle has a repositionable handle, a locking ring, and an elastic device. The elastic device biases against a handle locking mechanism that locks the repositionable handle at angular positions about an axis of the spindle. The elastic device further biases a locking ring into a locked position. The locking ring aids in holding the reamer spindle together. Removal of the locking ring against an elastic bias of the elastic means unfastens an end of the assembly in order to facilitate disassembly and/or cleaning. Adjustment of the position of the handle about the spindle enables the palm/grip of each hand to be changed in order to provide maximum control in different orientations.

Abstract: An elongated cutting tool (10, 110) intended to plunge cut a blind form in a bone using a plurality of teeth (30, 130) arranged on the tool. At least one of the teeth is an undercut tooth (30, 130) having a cutting edge (470, 570). The undercut tooth (30, 130) has a profile defined substantially along a primary relief angle (480, 580) measured from a vertical reference plane (477, 577) passing though the cutting edge (470, 570) and by a positive rake angle (485, 585) measured from a horizontal reference plane (472, 572) passing through the cutting edge (470, 570). The undercut tooth (30, 130) has a parabolic, non-circular relief (490, 590) along which bone chips are guided substantially away from the bone being cut, thereby avoiding capturing debris in the teeth and, consequently, avoiding overstressing the bone during cutting.