An anchor can be coupleable to a bone, where the anchor includes a head, a shank, a first extension, and a second extension. The head can include a distal head portion and a proximal head portion, where the proximal head portion can be open at a proximal end of the head. The shank can extend distally from the distal head portion, where the shank including a threaded portion configured to engage the bone. The second extension can be opposing the first extension, and the second extension can include a second proximal support coupled to a second end of a first elongate portion, where a first proximal support can extend transverse to the longitudinal axis, and the first proximal support portion and the second proximal support portion can be separated in a first condition and can be engaged to transfer forces there between in a second.
