Subchondral hematomas have been found with arthroscopy in one third of patients with dislocated distal radial fractures. The aim of the present, prospective study was to determine whether these hematomas might cause radiographic osteoarthrosis. We studied 41 patients (age 20-57 years, 22 women) with a dislocated distal radial fracture. At the time of fracture, 12 patients had subchondral hematomas in a radiocarpal compartment without a fracture line, as defined by arthroscopy. The 1-year follow-up included clinical and radiographic examinations. At follow-up, radiographic subchondral bone plate changes occurred in unfractured compartments in 8 patients, of whom 7 had had a previous arthroscopically diagnosed subchondral hematoma (p = 0.02) in the same compartment. Of the 8 patients with radiographic changes, 4 had also developed joint space narrowing (osteoarthrosis (OA) grade 1) after 1 year and 6 after 3 years. All but 1 had had a hematoma in the same compartment. More importantly, 3 of the 16 patients with entirely extra-articular fractures had subchondral bone plate changes in a compartment corresponding to a previous subchondral hematoma (p = 0.02). One of these had also developed joint space narrowing. The patients with radiographic changes had a worse outcome, as measured with the Gartland and Werley wrist score (p = 0.06). In conclusion, subchondral hematomas in distal radial fractures can lead to early onset of mild OA and worse outcome after 1 year.