Fracture of the distal radius is the most common wrist injury. Treatment of complex intra-articular fractures of the distal radius requires an accurate diagnosis of the fracture pattern and a thoughtful approach to fixation. We propose a new term, sustentaculum lunatum, for the palmar lunate facet. The sustentaculum lunatum deserves specific attention because of its importance in load transmission across the radiocarpal joint. It is also key to restoring the anatomy of the palmar distal radial metaphysis during internal fixation. We provide a review of the structure and function of the sustentaculum lunatum and describe fixation techniques. This article is intended to promote awareness of this fragment in the treatment of fractures of the distal radius.