Abstract: 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.

Abstract: An expandable augment system is provided for use with an acetabular cup. The expandable augment system can include an expandable augment module that is adjustable in size and that can be adjusted incrementally between a fully collapsed state and an expanded state. A first portion of the expandable augment module is attachable to an outer surface of an acetabular cup and a second portion of the expandable augment module is attachable to bone or to a fixed augment module (e.g., a fixed angle augment module) that is attached to bone and interposed between the adjustable augment module and bone.

Abstract: Off-center liners can be used with an acetabular cup in hip replacement or revision surgical procedures. The liners (of metal or plastic) can be laterally spaced from the acetabular cup, angled relative to the acetabular cup and/or have an opening that is offset relative to the axis of the acetabular cup. The liners have an orientation indicator that identifies where the liner should be impacted (e.g., impaction location or point) by the impactor to ensure the liner is impacted in a square manner relative to the acetabular cup.

Abstract: A method for generating intraoperative surgical guidance during a knee arthroplasty includes: preceding resection of a first bone and a second bone in a knee of a patient, generating a first ligament tension curve for a first ligament in the knee; generating a second ligament tension curve for a second ligament in the knee; storing a first target tension curve for the first ligament based on the first ligament tension curve; and, succeeding resection of the first bone and succeeding placement of a first test implant on the first bone, generating a third ligament tension curve for the first ligament; characterizing a first phase difference between the third ligament tension curve and the first target tension curve; and in response to the first phase difference exceeding a threshold negative phase difference, outputting a first prompt to a surgeon to further resect the first bone proportional to the first phase difference.

Abstract: 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.

Abstract: One variation of a method includes: accessing a virtual patient model defining a target resected contour of a hard tissue of interest; after resection of the hard tissue of interest during a surgical operation, accessing an optical scan recorded by an optical sensor facing a surgical field occupied by a patient, detecting a set of features representing the patient in the optical scan, registering the virtual patient model to the hard tissue of interest in the surgical field based on the set of features, and detecting an actual resected contour of the hard tissue of interest in the optical scan; and calculating a spatial difference between the actual resected contour of the hard tissue of interest and the target resected contour of the hard tissue of interest represented in the virtual patient model registered to the hard tissue of interest in the surgical field.

Abstract: One variation of a method includes: accessing a virtual patient model defining a target resected contour of a hard tissue of interest; after resection of the hard tissue of interest during a surgical operation, accessing an optical scan recorded by an optical sensor facing a surgical field occupied by a patient, detecting a set of features representing the patient in the optical scan, registering the virtual patient model to the hard tissue of interest in the surgical field based on the set of features, and detecting an actual resected contour of the hard tissue of interest in the optical scan; and calculating a spatial difference between the actual resected contour of the hard tissue of interest and the target resected contour of the hard tissue of interest represented in the virtual patient model registered to the hard tissue of interest in the surgical field.

Abstract: One variation of a method includes: accessing a virtual patient model defining a target resected contour of a hard tissue of interest; after resection of the hard tissue of interest during a surgical operation, accessing an optical scan recorded by an optical sensor facing a surgical field occupied by a patient, detecting a set of features representing the patient in the optical scan, registering the virtual patient model to the hard tissue of interest in the surgical field based on the set of features, and detecting an actual resected contour of the hard tissue of interest in the optical scan; and calculating a spatial difference between the actual resected contour of the hard tissue of interest and the target resected contour of the hard tissue of interest represented in the virtual patient model registered to the hard tissue of interest in the surgical field.

Abstract: 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.

Abstract: One variation of a method for augmenting a surgical field with virtual guidance content includes: accessing a scan representing a tissue of a patient; combining the scan with a generic virtual anatomical model to define a custom virtual anatomical model of the tissue; defining a cut trajectory along an intersection between a virtual model of a surgical implant and the custom virtual anatomical model of the tissue; aligning a virtual cut surface to the cut trajectory to locate the virtual model of the surgical guide relative to the custom virtual anatomical model; accessing an image of a surgical field; detecting the tissue in the image; aligning the custom virtual anatomical model to the tissue detected in the image; defining a target real location for a real surgical guide in the surgical field; and generating a frame depicting the target real location of the surgical guide in the surgical field.

Abstract: 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.