Abstract: A method for assessing the orthopaedic performance of a joint of a patient can comprise implanting at least a first and second RF wirelessly detectable markers in first and second bones associated with a site and determining and storing their positions before a surgical procedure is performed. The procedure can be carried out on the site and the positions of the first and second markers can be detected and stored after the procedure has been completed. The detected positions can be used to generate a representation of the orthopaedic performance of the joint after the procedure.

Abstract: A method for assessing the orthopaedic performance of a joint of a patient can comprise implanting at least a first and second RF wirelessly detectable markers in first and second bones associated with a site and determining and storing their positions before a surgical procedure is performed. The procedure can be carried out on the site and the positions of the first and second markers can be detected and stored after the procedure has been completed. The detected positions can be used to generate a representation of the orthopaedic performance of the joint after the procedure.

Abstract: An implantable medical device, which comprises a device substrate, a coating on the substrate which includes a drug, and a protective layer which overlies the coating. The protective layer comprises a polymer selected from the group consisting of polylactic acid, polyglycolic acid and a lactic acid/glycolic acid copolymer having a weight average molecular weight of not more than 40,000.

Abstract: A method for assessing the orthopaedic performance of a joint of a patient can comprise implanting at least a first and second RF wirelessly detectable markers in first and second bones associated with a site and determining and storing their positions before a surgical procedure is performed. The procedure can be carried out on the site and the positions of the first and second markers can be detected and stored after the procedure has been completed. The detected positions can be used to generate a representation of the orthopaedic performance of the joint after the procedure.

Abstract: A bone broach is formed from a plurality of substantially planar members which are positioned adjacent to each other with each of the substantially planar members attached to at least one other substantially planar member. At least some of the substantially planar members defines at least one cutting profile at its perimeter. The plurality of substantially planar members include a first group of substantially planar members defining planes which are substantially parallel to each other, and at least one additional substantially planar member defining a plane which is angled relative to the planes defined by the first group of substantially planar members.

Abstract: A knee joint prosthesis which comprises a tibial component (4, 6) and a femoral component (2). The femoral component has condyles (14, 16) which act against the tibial component, directly or indirectly, during flexing of the knee. A cam (20) on the femoral component acts against a post (26) on the tibial component at high flex angles. The surface of the post which is contacted by the cam at high flex angles is convex when the post viewed generally perpendicular to the tibial bone contact and bearing surfaces, and the femoral bearing surface which is provided by the cam, where it contacts the convex surface of the post at high flex angles, is locally concave (32) when viewed along the surface of the post which contacts the cam so that the area of contact between the post and the cam is greater at high flex angles than at lower flex angles.

Abstract: An implantable medical device, which comprises a device substrate, a coating on the substrate which includes a drug which is highly soluble in water, and a protective layer which overlies the coating. The protective layer comprises a polymer selected from the group consisting of polylactic acid, polyglycolic acid and a lactic acid/glycolic acid copolymer having a weight average molecular weight of not more than 40,000.

Abstract: A surgical instrument system includes a tool (2) including an elongate shaft which defines the tool axis. The shaft bears a plurality of marker rings (10, 11, 12) arranged in a predetermined pattern on the surface of the shaft so that they extend around the shaft axis. The system includes at least two receiving devices (14) which are spaced apart for receiving stereoscopic signals from the rings on the tool, and a data processor (16) for analyzing the signal from the rings and generating information relating to the position and orientation of the tool relative to the receiving device.

Abstract: A computer assisted surgery method and apparatus for determining a change in a property of a joint of a patient caused by an arthroplasty procedure is described. The relative position of a first bone and a second bone of the joint is determined with the joint in a first position. The position of a pre-operative center of motion of the joint relative to the first bone is determined. The position of the second bone relative to the pre-operative center of motion is determined using the relative position of the first and second bones. The position of a post-operative center of motion resulting from a prosthetic component to be used in the joint is determined. The position of the second bone relative to the post-operative center of motion is determined. Any change in the property of the joint. is determined from the difference between the position of the second bone relative to the pre-operative center of motion and the position of the second bone relative to the post-operative center of motion.

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 bone broach is formed from a plurality of substantially planar members which are positioned adjacent to each other with each of the substantially planar members attached to at least one other substantially planar member. At least some of the substantially planar members defines at least one cutting profile at its perimeter. The plurality of substantially planar members include a first group of substantially planar members defining planes which are substantially parallel to each other, and at least one additional substantially planar member defining a plane which is angled relative to the planes defined by the first group of substantially planar members.

Abstract: A surgical instrument alignment guide comprising a mount (2) arranged to be coupled to a bone of a patient, an alignment rod (4), a guide rod (24) and an indicator (26). The alignment rod (4) has a first end pivotally coupled to the mount (2) such that the inclination of the alignment rod (4) relative to the mount (2) is adjustable. The guide rod (24) is couplable to a second end of the alignment rod (4) at an adjustable angle and orientation such that the guide rod (24) can extend transverse to the alignment rod (4). The indicator (26) is coupled to the guide rod (24) to indicate when the guide rod (24) lies at a desired angle relative to a horizontal axis. Also disclosed is a method of aligning a surgical instrument using the surgical instrument alignment guide.

Abstract: A distractor instrument for use in knee joint surgery is provided that includes a tibial plate, a femoral plate, a tibial arm having a plate end and a control end, wherein the tibial plate is fastened to the plate end of the tibial arm at its anterior edge, and wherein, when the tibial plate is engaged with the tibia, the tibial arm is configured to extend from the tibial plate generally medially or laterally of the knee joint. The distractor instrument also includes a femoral arm having a plate end and a control end, wherein the femoral plate is fastened to the plate end of the femoral arm, and wherein, when the femoral plate is engaged with the femur, the femoral arm extends from the femoral plate generally aligned with the tibial arm.

Abstract: A method for assessing the orthopedic performance of a joint of a patient can comprise implanting at least a first and second RF wirelessly detectable markers in first and second bones associated with a site and determining and storing their positions before a surgical procedure is performed. The procedure can be carried out on the site and the positions of the first and second markers can be detected and stored after the procedure has been completed. The detected positions can be used to generate a representation of the orthopedic performance of the joint after the procedure.

Abstract: An alignment guide is provided having a shaft having a longitudinal axis. The guide includes a housing configured to be attached to the shaft and rotatable about a first axis substantially perpendicular to the longitudinal axis. The housing includes a base and a plate. The base is attached to the shaft, and the plate is rotatable about the first axis relative to the base. The guide also includes a guide arm having a first portion and a second portion, the first portion being attached to the housing and extending from the housing along a second axis, the second portion extending from the first portion at a first predetermined angle.

Abstract: A knee joint prosthesis which comprises a tibial component (4, 6) and a femoral component (2). The femoral component has condyles (14, 16) which act against the tibial component, directly or indirectly, during flexing of the knee. A cam (20) on the femoral component acts against a post (26) on the tibial component at high flex angles. The surface of the post which is contacted by the cam at high flex angles is convex when the post viewed generally perpendicular to the tibial bone contact and bearing surfaces, and the femoral bearing surface which is provided by the cam, where it contacts the convex surface of the post at high flex angles, is locally concave (32) when viewed along the surface of the post which contacts the cam so that the area of contact between the post and the cam is greater at high flex angles than at lower flex angles.

Abstract: A tool for extracting a pin from a substrate comprises a first lever arm with a body part having a cavity in which the free end of a pin can be received, and a second lever arm which can pivot relative to the first lever arm. A jaw component is provided within the body part which can be actuated from an unlocked position in which a pin within the jaw component can slide freely past the jaw component, and a locked position in which the pin is gripped by engagement of the jaw component with the side wall of the pin, and a support is provided which can slide relative to the body part, in a direction towards the substrate from which the pin is to be extracted. Initial movement of the first lever arm relative to the second lever arm causes the jaw component to be actuated from its unlocked position to its locked position so that an inserted pin is gripped by the jaw component.

Abstract: An alignment guide is provided having a shaft with a longitudinal axis and a guide arm having a first portion, a second portion and a third portion. The first portion is attached to the shaft and configured to be rotatable about a first axis substantially perpendicular to the longitudinal axis. The second portion extends from the first portion at a first predetermined angle along a second axis. The third portion extends from the second portion at a second predetermined angle.

Abstract: A surgical instrument alignment guide comprising a mount (2) arranged to be coupled to a bone of a patient, an alignment rod (4), a guide rod (24) and an indicator (26). The alignment rod (4) has a first end pivotally coupled to the mount (2) such that the inclination of the alignment rod (4) relative to the mount (2) is adjustable. The guide rod (24) is couplable to a second end of the alignment rod (4) at an adjustable angle and orientation such that the guide rod (24) can extend transverse to the alignment rod (4). The indicator (26) is coupled to the guide rod (24) to indicate when the guide rod (24) lies at a desired angle relative to a horizontal axis. Also disclosed is a method of aligning a surgical instrument using the surgical instrument alignment guide.

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.