Abstract: Apparatus for aligning a surgical instrument, such as an acetabular cup inserter, with a direction guide that defines an orientation in space for insertion of the cup. The apparatus comprises a parallel guide having a first arm for alignment with the direction guide and a second arm spaced from the first arm but maintained in parallel relationship with it. The cup inserter can be aligned with the first arm by aligning it with the second arm.

Abstract: An adapter for a tripodal stereotactic reference frame for use in arthroplastic surgery mounts a third leg of the frame at an angle with respect to the other two legs to facilitate use of said frame with varying surgical exposures.

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: A system and method receive a request for a patient-specific surgical plan, create the requested plan, and provide it to a surgeon. A Planning server may receive information regarding a patient, such as one or more files or objects, such as an image of the part of the patient's anatomy that is to be operated on, and an order from a surgeon for a surgical plan. A Plan Development client may include a surgical planning module that accesses the digital image from the Planning Server, and creates a computer-generated, three-dimensional model of the patient anatomy. The planning module of the Plan Development client also may create an electronic surgical plan, and may transmit the plan to the Planning server. The ordering surgeon may be notified of the availability of the plan, and may access the plan stored at the Planning server through a surgeon client. The ordering surgeon may utilize the remotely generated surgical plan during the surgical procedure on the patient.

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 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 pelvic coordinate system is produced from a single near AP intra-operative image of the patient, obviating the need for use of a patient tracker.

Abstract: A system and method for use during hip surgery includes a position frame that is removably secured to the patient's femur. The system further includes a tracking unit and navigation engine that establish a pelvic coordinate system and, with the patient's leg placed in a predetermined orientation, capture the location of the femoral position frame within the pelvic coordinate system. The system further includes an image generator configured to display one or more images for directing the surgeon to return the patient's leg to the predetermined orientation following a trial reduction based upon the previously captured position. A leg change determination engine compares the current, post-reconstruction position of the femoral position tracking frame with the previously captured, pre-reconstruction position to derive leg length, offset, and anterior-posterior change values. The change values are then provided to the surgeon for evaluating the suitability of the trial reduction.

Abstract: A surgical retractor comprising a retractor body having a site portion and handle portion, and an impactor body on the retractor body. The impactor body is positioned and configured for use in impacting the site portion of the surgical site. An impaction axis of the impaction body is preferably substantially aligned with an axis of the site portion of the impactor body. The impactor body is preferably attached to the retractor body at a junction between the site portion and the handle portion of the retractor body. In one embodiment, the impactor portion is configured to selectively mate with an impactor extension member to thereby optionally receive direct impaction on the impactor portion or indirect impaction through the impactor extension member.

Abstract: A system and method for use during hip surgery includes a position frame that is removably secured to the patient's femur. The system further includes a tracking unit and navigation engine that establish a pelvic coordinate system and, with the patient's leg placed in a predetermined orientation, capture the location of the femoral position frame within the pelvic coordinate system. The system further includes an image generator configured to display one or more images for directing the surgeon to return the patient's leg to the predetermined orientation following a trial reduction based upon the previously captured position. A leg change determination engine compares the current, post-reconstruction position of the femoral position tracking frame with the previously captured, pre-reconstruction position to derive leg length, offset, and anterior-posterior change values. The change values are then provided to the surgeon for evaluating the suitability of the trial reduction.

Abstract: A surgical retractor comprising a retractor body having a site portion and a handle portion, and an impactor body on the retractor body. The impactor body is positioned and configured for use in impacting the site portion in the surgical site. An impaction axis of the impaction body is preferably substantially aligned with an axis of the site portion of the impactor body. The impactor body is preferably attached to the retractor body at a junction between the site portion and the handle portion of the retractor body. In one embodiment, the impactor portion is configured to selectively mate with an impactor extension member to thereby optionally receive direct impaction on the impactor portion or indirect impaction through the impactor extension member.

Abstract: A modular hip prosthesis includes a femoral stem, a spherical head and a coupling member extending from the head defining a neck whose lower end forms a base which plugs into a socket at the top of the stem to form a tapered neck/stem junction. That junction is aligned with the stem axis and has a cross-section with opposite sides that extend generally parallel to the sides of the stem. With such an arrangement, that junction may be relatively long and have a relatively large cross-sectional area thus making a strong junction even in smaller femoral implants.

Abstract: Systems, methods and processes for computer-assisted soft tissue balancing, including ligament balancing, determining surgical cuts, and positioning or placement of the components of the prosthetic knee during TKR. The improved methods, systems, and processes consider and correlate anatomical landmarks and dynamic interactions of the knee bones and soft tissues. The improved methods, systems and processes resolve several problems related to the prosthetic knee component positioning and soft-tissue balancing during computer-assisted TKR. The improved methods, systems and processes are flexible and versatile, provide reliable recommendations to the surgeon, and improve restoration of the knee function and patient recovery.

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 system and method for determining tibial rotation is disclosed. The system includes a first fiducial, a second fiducial, a position and orientation sensor, a computer, and a monitor. The first fiducial is connected to a first part, and the second fiducial is connected to a second part. The position and orientation sensor tracks the first fiducial and the second fiducial. The computer has a memory, a processor, and an input/output device. The input/output device receives data from the position and orientation sensor. The processor processes the data to identify a first axis of the first part and a second axis of the second part. The processor constructs a reference plane through the second axis and orthogonal to the first axis. The monitor is connected to the input/output device and displays a rendering of the reference plane.

Abstract: A modular hip prosthesis includes a femoral stem, a spherical head and a coupling member extending from the head defining a neck whose lower end forms a base which plugs into a socket at the top of the stem to form a tapered neck/stem junction. That junction is aligned with the stem axis and has a cross-section with opposite sides that extend generally parallel to the sides of the stem. With such an arrangement, that junction may be relatively long and have a relatively large cross-sectional area thus making a strong junction even in smaller femoral implants.

Abstract: A minimally invasive hip replacement surgical procedure that is also tissue preserving is disclosed. By making a superior incision, rather than a posterior incision, neither the posterior hip capsule, nor the gluteus medius or minimus are dissected. This results in improved post-operative results in the form of less dislocations and better healing.

Abstract: An improved acetabular impactor, especially suitable for use in minimally invasive hip surgeries, is disclosed. The impactor is simple in design and operation and spatially optimized. In particular, the impactor is designed to remotely detach the acetabular shell from the impactor via different potential mechanical connections.

Abstract: A modular prosthesis allows two portions to be secured together with a selectable discrete relative angular orientation. A spline secured to one portion has projections which engage grooves in a cavity of the other portion to prevent angular motion between the portions. The spline and the cavity may be tapered to allow a pressure fit. Teeth secured to each portion may be used instead of a spline to secure the two portions in a selected discrete angular orientation. Alternatively, a pin may secure the portions together to prevent their relative angular movement. An additional securing means may also be used in combination with each of the above embodiments to further secure the two portions together.

Abstract: An electrically heated knife blade is mounted on a carriage for moving the blade across a strip of elastomeric material. The carriage is propelled by a constant force provided by a pneumatic cylinder in communication with a source of constant air pressure so that the cutting speed is automatically increased at sections of strip material which are relatively thin and the cutting speed is automatically decreased at sections of strip material which are relatively thick. Sensors for determining the position of the relatively thick sections may be connected to the source of electricity for heating the knife blade to increase the voltage while cutting the relatively thick sections and thereby provide for a substantially constant cutting speed across the strip of elastomeric material. A tire tread is bent at the location the knife blade is moved across the tread to provide matching cut ends for splicing on a tire building drum.