The authors describe a new method of radiologic measurement of "Haglund's deformity", based on a radiologic study of 31 feet operated for posterior heel pain and more especially for calcaneal tendinopathies related to deformity of the calcaneus, and on a series of 60 asymptomatic feet. This angular approach requires a lateral weight-bearing view and proved positive in 85% of symptomatic feet, with only 14% of false-positives in the control group. It thus proves markedly superior to previously described radiologic formulations, since it allows not only for the size and site of the deformity of the posterosuperior part of the calcaneus but also for the angle of verticalization of the latter.