In a series of 260 fractures of one or both tibial condyles that were treated at the Department of Orthopaedic Surgery I, Sahlgren Hospital, Goteborg, Sweden, between 1959 and 1965, the main indication for surgical treatment was clinical evidence of instability of the extended knee joint. Two hundred and four of the patients were followed for 7.3 years and the results were presented in 1973. A longer follow-up of twenty years on 102 of these 204 patients is reported in this paper. The distributions of fracture types and treatments were similar in the two series and, in general, the results were unchanged. Ninety per cent of the patients achieved an excellent or good result and 10 per cent achieved a fair or poor result. The inferior results were seen in the unstable split-depressed and depressed fractures in which a depression of the articular surface of more than ten millimeters persisted. The results of this study support the conclusions that were made in 1973: that patients without clinical impairment of lateral or medial stability of the extended knee joint should be treated non-operatively, irrespective of the roentgenographic appearance of the fracture, and that those with an unstable knee joint should be treated operatively. We have achieved satisfactory results after percutaneous cerclage wiring in split fractures and after open reduction and bone-grafting in split-depressed and depressed fractures.