A diameter sizing tool for use in reversion of total knee arthroplasty, the diameter sizing tool including a body having an upper surface, a lower surface, and a peripheral edge, a central cutout disposed through the body from the upper surface to the lower surface, and a plurality of sizing through-holes circumferentially disposed in the body and radially towards the peripheral edge.

A reverse shoulder system can include, for example, a glenoid baseplate comprising a longitudinal axis, the glenoid baseplate further including a stem and a central channel within a sidewall of the stem. The stem can include a longitudinal axis. The longitudinal axis of the glenoid baseplate can be angled with respect to the longitudinal axis of the stem, wherein the longitudinal axis of the glenoid baseplate is not perpendicular with respect to the longitudinal axis of the stem. Other components including a glenosphere, tools, and methods of use are also disclosed.

Described herein are reverse shoulder devices and related systems, methods, and kits useful in implanting a humeral implant in the humerus bone. In some embodiments, a humeral implant device is described that includes a liner, a tray, and an adaptor. In some embodiments, the humeral implant further includes a stem. In some embodiments, the liner is configured to receive a glenosphere. In some embodiments, an offset tool is described that comprises a distal portion configured to interface with a humeral implant stem and a proximal portion configured to interface with a humeral implant tray. In some embodiments, an offset tool is described for determining a desired size of an adapter for use with a humeral implant. In some embodiments, the offset tool includes a trial tray assembly, an outer shaft, and an inner shaft.

A system for sizing the resected surface to provide metaphyseal referencing and to properly guide a tool into a central portion of the canal in the diaphysis. The system can include a sizing feature to approximate the size of the metaphysis. The system can also include a base configured to contact the metaphysis and a guide feature configured to guide a tool along a central portion of the canal in the diaphysis.

A diameter sizing tool for use in reversion of total knee arthroplasty, the diameter sizing tool including a body having an upper surface, a lower surface, and a peripheral edge, a central cutout disposed through the body from the upper surface to the lower surface, and a plurality of sizing through-holes circumferentially disposed in the body and radially towards the peripheral edge.

Apparatus for measuring size of a cup for hip arthroplasty according to the present disclosure includes a scale plate marked with a scale to measure size, a first leg portion fixed to one end of the scale plate, and a second leg portion slidably moved relatively to the first leg portion along the scale plate, in which the second leg portion is marked with reading line. First and second jaws for contacting the cup are provided with 180 rotational symmetry on ends of the first and second leg portions, respectively. Central portions of the first and second jaws are bent to protrude in direction in which the first and second leg portions are farther away from each other, so that when contacting inner diameter of the cup, the jaws form one-point contact with the cup, and when contacting outer diameter of the cup, form two-point contact with the cup.

A system for sizing the resected surface to provide metaphyseal referencing and to properly guide a tool into a central portion of the canal in the diaphysis. The system can include a sizing feature to approximate the size of the metaphysis. The system can also include a base configured to contact the metaphysis and a guide feature configured to guide a tool along a central portion of the canal in the diaphysis.

A hip arthroplasty system, intended to improve anatomic placement and maintain bone stock, includes a nail for insertion into an intramedullary canal of a femur, screw holes generally perpendicular to the nail, and a hole having a transverse axis. The system also includes a bone anchor having an opening for a cut-off femoral neck, a neck component having a longitudinal body and a seat for the femoral head, a femoral head, and an acetabular cup assembly. A jig is provided for implanting the system and includes a guide that orients relative to the nail, attachment hardware, a rail adapted to extend parallel to the transverse axis of the nail, and a second guide slidably displaceable along the rail. The system provides significant adjustability and retains maximum bone for the possibility of revision.