Abstract: Surgical knives are disclosed, for initiating percutaneous access to a surgical site. The knife has a body with a rear handle and a front cutter portion. It may have a central cannulation to receive a guide wire, along a front-to-rear operating axis. The cutter portion has first and second blades opposed across the axis, each having an outward cutting edge directed laterally outwardly relative to the operating axis and a flat outward face also directed laterally outwardly relative to the operating axis and transversely to the respective outward cutting edge. The first and second outward faces of the two blades converge forwardly to their tip points, which lie close to the axis, and their cutting edges are oppositely directed. Alternatively a single blade may be used, forwardly convergent with the axis.

Abstract: The present application relates to a system (10) for anatomical reduction of bone fractures in which first and second manipulators (12, 14), and optionally a third manipulator (16), are attached to fragments of the fracture to be reduced by percutaneous attachment devices such as Schanz pins. An underlying processing system determines, from one or more medical images of the fracture, manipulations such as rotations and translations of the bone fragments required to correctly reposition and align the fragments for optimum healing of the fracture. The processing system provides motion reference signals (position, speed, acceleration and force) for a controller, which in turn causes the first, second and third manipulators (12, 14, 16) to effect the calculated manipulations.