The radius is one of two bones in your forearm. When holding your hands out in front of you with palms up, the radius is the bone on the outside or on the side your thumb is pointing to. This bone may break from falling on an outstretched hand or from blunt force trauma. Symptoms include pain, swelling, bruising, and/or weakness with wrist movement. The goal of treatment is to realign the bone to allow for proper bone healing.