A surgical instrument includes a housing, an outer shaft, an inner shaft, a trial sizer, a rod, and a head. The outer shaft is operatively coupled with the housing such that rotation of the housing causes axial displacement of the outer shaft. The outer shaft includes a keel cutter configured to form a channel in a vertebral body. The inner shaft disposed within the outer shaft. The trial sizer is configured to be received in intervertebral space. The trial sizer includes a pair of wings transitionable between a retracted position and an extended position in which the pair of wings extends transversely outward. The head is connected to the rod, wherein the head is operatively coupled with the pair of wings such that axial displacement of the rod causes transition of the pair of wings between the retracted and extended positions.