BÖHLER AND GISSANE ANGLES OF THE CALCANEUSWHAT ARE THE NORMAL RANGES?

Abstract

Introduction: Identifying normal ranges for calcaneal angles is important for the assessment of morbidity after calcaneal fractures. We have evaluated the distribution and normal ranges of calcaneal angles.

Method: A retrospective study was performed to review 105 lateral radiographs of 87 patients (62 female, 43 male). Radiographs with fractures, deformities and fusion were excluded. The mean age was 42.6 (18–79). Böhler and Gissane angles were measured by the same surgeon with the macros of the Hipax program. T test and Pearson correlation coefficients were used for statistical analysis with SPSS software with a significance level of P< 0.05.

Results: The mean Böhler angle was 34.4±4.12º (range 23–44), the Gissane angle was 116.4±6.23º (range 103–133). There was no statistically significant difference between the mean Böhler angles of women (34.9º±4.5) and men (33.9º±3.79) (t test: p> 0.05). There was no correlation between the two angles (r=−0.044; p> 0.05). There was a negative correlation between the Böhler angle and age (R=−0.36; P< 0.01). The regression equation of this correlation was y=−0.01x+38.51. There was no significant correlation between the Gissane angle and age (r=−0.046; p> 0.05).

Discussion: The reported ranges for Böhler and Gissane angles are widely spread (14–50 and 95–130, respectively). Our results were consistent with 4 (Hauser; Loucks; Didia; Igbigbi) of the 5 previous studies. However, unlike the other studies Böhler angle results did not show sex dimorphism and revealed a negative correlation with aging. Posterior facet collapse may be the cause of this correlation.