The calcaneal angle in indigenous Malawian subjects

Abstract

Background: The calcaneus is an important tarsal bone which is configured in such a way that it forms the calcaneal angle when a person stands erect. This angle is assessed in the evaluation of calcaneal fractures but literature is scanty on African subjects.Objective: To establish values for Malawians and compare them with those for Ugandans and Nigerians previously studied.Methods: 220 lateral radiographs of the ankle comprising 118 male and 102 female indigenous Malawians aged 18–54 years were examined and the angle measured.Results: The highest frequency of the angle occurred in the 30°–34° class limit with a mean and SD of 30.11°±6.29° (range, 14° to 45°). There was no difference in the angle between left and right feet (P>0.5) and between male and female subjects (P>0.5) as was the case with Nigerians. Significant differences were, however, observed between Malawian and Ugandan men, Malawian and Nigerian men, Malawian and Nigerian women (P<0.001); and differences also occurred between Malawian and Ugandan women (P<0.01).Conclusion: Our study reinforces the need to establish the normal range of the angle in a given population. Also stressed is the clinical importance of the angle in orthopaedic practice. We recommend that the lower limit of the angle in a given population be represented by the mean–2SD, which was found to be 17.53° in our study.