Valgus deformity is a relatively common occurrence in rheumatic or degenerative disease of the tarsus. Frequently the angular deformity can exceed 25° ; in these situations dislocations of talo-calcaneal and/or talo-navicular joints can be observed. These conditions are usually progressive and affect the walking ability of the patient The goal of the study is to present a series of patients surgically treated in order to evaluate the best solutions and the problems of the surgical technique. In the period 1996–2002, 22 patients were treated for significant valgus deformity of the rearfoot; 16 were affected by rheumatoid arthritis and six by a degenerative pathology. In all cases combined talo-navicular and talo-calcaneal arthrodesis was performed. In seven patients a bone graft was used to fill bone defects. The follow-up was 5.3 years. The results were evaluated using the AOFAS score for rearfoot; fusion was achieved in all but one case (talo-navicular joint). All patients were satisfied regarding subjective results (pain and function). Combined arthrodesis of talo-calcaneal and talo-navicular joints is an effective method of treating significant valgus deformity of the hindfoot; fixation by screws for talo-calcaneal joint and by staples or screw for talo-navicular joint is the recommended method for synthesis.