System, including methods, apparatus, and kits, for expanded bone fixation with bone plates. A bone plate and an extension plate may be provided. The bone plate may be secured to a proximal portion of a humerus and overlapping the greater tuberosity of the humerus using fasteners received in openings defined by the bone plate. The extension plate may be attached to the bone plate and the humerus using (a) a fastener disposed in an aperture defined by the first end region and in threaded engagement with the bone plate and (b) a fastener received in an aperture defined by the second end region and extending into the humerus. The attached extension plate may extend from a position over the greater tuberosity to a position over the lesser tuberosity of the humerus such that the intermediate region is disposed over a biceps tendon.