Abstract Thirty-one patients with displaced intra-articular fracture of the os calcis who were admitted to Queen Mary Hospital, Hong Kong from 1989 to 1991 and who underwent open reduction and internal fixation and bone grafting of the os calcis, were followed up for at least 30 months. Pre- and postoperative X-rays were taken. Functional results were assessed clinically in terms of pain, deformities, activities and motion loss. The majority of the patients had acceptable functional outcome. The results were analysed in an attempt to correlate with the fracture pattern.