Abstract: A surgical navigation method utilizing a computer system. The method includes the steps of: (a) fixing a camera relative to a surgical site on a patient such that the camera does not move relative to the surgical site; (b) restraining the body portion of the patient which includes the surgical site relative to an operating table supporting the patient, such that the body portion does not move relative to the operating table; and (c) detecting with the camera the position of a medical instrument having a tracker array.

Abstract: A length adjustable modular screw includes a neck assembly and a shank. The neck assembly has proximal and distal ends and includes an expander component and a collet component that are slidably engagable by insertion of the expander component in a through channel of the collet component along a common axis. The length adjustable modular screw also includes a shank suitable for insertion and retention within a bone, the shank including a threaded portion between proximal and distal ends and a socket adapted to coaxially receive at least a portion of the distal end of the neck assembly. The length adjustable modular screw has a length that is selected by splaying at least a portion of the distal end of the engaged expander and collet components of the neck assembly within the socket of the shank.

Abstract: A surgical guidance device is cannulated for passage of a guidewire or pin and includes a hand grip and differential control assembly for driving the guidewire or pin and differentially driving a screw, such as but not limited to a pedicle screw, into bone. The differential control assembly resides in a housing, and includes a differential control assembly for gripping and locking or releasing the guidewire or pin and effecting directional movement (relative to the user holding the surgical guidance device) either distally into the bone or proximally away from bone to thereby drive or retract the guidewire. The differential control assembly also allows distal or proximal drive of a screw, such that one or both the guidewire and screw can be passed proximally or distally alone or together.