A surgical instrument for use in a knee joint replacement operation includes a reference block with a block rear face configured to bear on a resected femur, a stylus arranged on the reference block, a stylus tip configured to bear on the femur, and two reference feet that are spaced apart mediolaterally from one another and arranged on the reference block. Each reference foot has a foot upper face protruding beyond the block rear face. The foot upper faces are arranged in a common reference plane and are configured to bear on the femur. At least two reference bores extend from the block rear face. Each reference bore is configured to receive a reference pin. A compensation element is configured for form-fitting and/or force-fitting releasable connection to one of the reference feet. The compensation element has an upper face which comes to bear against a posterior condyle.

An orthopaedic joint replacement system is shown and described. The system includes a number of prosthetic components configured to be implanted into a patient's knee. The system also includes a number of surgical instruments configured for use in preparing the bones of the patient's knee to receive the implants. A method or technique for using the surgical instruments to prepare the bones is also disclosed.

A kinematic-axis locating device for knee arthroplasty includes two spoon-shaped arms and a linking piece. The two spoon-shaped arms are to be placed between a proximal tibia and a distal femur. Due to checking effects of ligaments on the proximal tibia and the distal femur, a medial condyle femur and a lateral condyle femur hold the two spoon-shaped arms on the tibial plateau using their respective curvatures. The linking piece provides a reference axis that is naturally defined by the two inserted and positioned spoon-shaped arms. The reference axis is roughly parallel to a kinematic axis upon which the medial condyle and the lateral condyle pivot against the tibial plateau. Articular surface resection can then be performed between the proximal tibia and the distal femur with reference to the reference axis.

In one embodiment, a method of planning implantation of a knee prosthesis is performed. Data is collected that is representative of a position of a tibia relative to a femur at a plurality of positions of the tibia relative to the femur through a range of motion of the knee. The data at each position of the plurality of positions includes: a medial maximum convergence of a low point on a medial femoral condyle and a medial tibial articular surface of the tibia and a lateral maximum convergence of a low point on a lateral femoral condyle and a lateral tibial articular surface of the tibia. The medial and lateral convergence locations from the plurality of positions are analyzed to determine a kinematic pattern that is then used to determine an implant position and an implant orientation for a tibial implant to be placed on a resected tibial surface.

Methods and apparatuses including apparatuses that can be used in a unicompartmental knee replacement procedure, a bicompartmental knee replacement procedure comprised of two unicompartmental knee replacements, a knee replacement procedure that utilizes a single femoral component and two unicompartmental tibial components, and other types of knee replacement procedures are disclosed. According to one example, an apparatus for guiding a tibial bone cut during knee replacement surgery is disclosed. The apparatus can comprise a mounting portion and a cutting portion. The mounting portion can be configured to couple with an alignment mechanism. The cutting portion can be connected to the mounting portion and can define a capture for a proximal cut. The cutting portion can have an aperture disposed adjacent a first end of the capture.

A modular system for total knee arthroplasty includes a modular trial implant assembly. The modular implant assembly includes an elongate shaft configured for insertion into an elongate cavity in a bone, a reamer removably coupleable to the elongate shaft via a connection that allows the reamer to rotate while the elongate shaft remains in a substantially fixed angular orientation. The reamer has an outer surface that tapers toward the distal end configured to form a tapered cavity in an end of a bone in which the reamer is inserted and rotated. The modular trial implant assembly further includes a trial implant removably coupleable to a proximal end of the reamer. A modular final implant assembly includes an elongate stem, a tapered body and an implant body, each having a size and shape that can substantially correspond to a size and shape of the elongate shaft, the reamer and the trial implant, respectively.

A patient-specific arthroplasty system comprising a database comprising preoperative data, ligament balancing tool data, and postoperative data associated with a plurality of patients, a preoperative evaluation module that receives preoperative data for a given patient, an analysis engine that analyzes the database, receives the preoperative data, and generates a surgical recommendation based on the preoperative data of the given patient and the analysis of the database, and a pin positioning block module that receives the surgical recommendation and determines a pin positioning block based on the surgical recommendation.

A unicompartmental orthopedic knee implant may include a tibial tray including a body having a joint-facing side, a bone-facing side opposite the joint-facing side, a side wall extending about a periphery of the body, and a channel extending through the bone-facing side from one of the joint-facing side or the side wall, the channel being angled relative to the bone-facing side of the body. The implant may also include a fixation element coupled to the body. The fixation element may include a rail for insertion into the channel of the body, a support extending from the rail, and a bone engagement feature connected to the support, the bone engagement feature including an edge operable to penetrate the tibia, wherein the bone engagement feature is inserted through the channel.

A distal femoral joint replacement system includes a femoral component having condylar articular surfaces, a stem extending from the femoral component, and a void filler for filling a bone void within a femur. The void filler includes a body and a plurality of legs extending from the body. The body has a sidewall defining an opening for receipt of the stem which extends along a length of the body and extends through the sidewall so as to form a side-slot in the sidewall that extends along an entire length of the sidewall. The plurality of legs each have a first end connected to the body and a second end remote from the body. The legs each have an outer surface that tapers between the first and second ends and is configured to register with a corresponding inner surface of a bone void when implanted in an end of the femur.

An apparatus comprising: a medical tool moveable to a desired orientation relative to a bone region for implantation of a medical implant; and an electronic orientation sensor transitionable between a first location fixed relative to the bone region of the patient and a second location on the medical tool; wherein, at the first location, the orientation sensor is adapted to record a reference orientation of the bone region of the patient, and, at the second location, the orientation sensor is adapted to determine an orientation of the medical tool relative to the reference orientation, wherein recording the reference orientation comprises measuring a gravity vector relative to the orientation sensor.