Radiologic Morphology of the Calcaneus

Abstract

The Fowler-Philip, calcaneal pitch, and total calcaneal angles define the radiologic morphology of the rearfoot. We studied these angles in healthy adolescents. We studied 141 feet. Patients with inflammatory or traumatic injuries were excluded. The mean participant age was 11.5 years. The Fowler-Philip, calcaneal pitch, and total calcaneal angles were measured on lateral weightbearing radiographs. The statistics included descriptive, sample size (α=0.05 and β=0.20), the Student t test, and analysis of variance; P < .05 was considered significant. The samples were 141 and 35 radiographs for the Fowler-Philip and calcaneal pitch angles, respectively. Ninety percent, 25.1%, and 97.4% of the adolescents had normal Fowler-Philip, calcaneal pitch, and total calcaneal angles, respectively. In addition, 9.9%, 74.9%, and 2.6% of the values were outside the reference ranges, respectively. The Fowler-Philip angle decreased and the calcaneal pitch angle increased significantly with age (P = .0005). The total calcaneal angle did not change with age (P = .65). The mean angle values in a pediatric population did not differ from those in adults. We found a high percentage of calcaneal pitch angles outside the reference range. Age influenced the Fowler-Philip and calcaneal pitch angles but not the total calcaneal angle.