A computer-assisted external fixation apparatus and method comprises an external fixation application for assisting, guiding, and planning an external fixation procedure. The external fixation application cooperates with a tracking system to acquire kinematic data corresponding to a selected joint during manipulation of the selected joint and/or acquire image data of patient anatomy and determine a kinematic parameter for the selected joint using the kinematic and/or image data, such as an axis of rotation or plane of movement. The external fixation application may then be used with the tracking system to provide real-time alignment information for alignment of an external fixator based on the information associated with the determined kinematic parameter.