Morphological analysis of posterior malleolus fracture fragments under different injury mechanisms / 国际外科学杂志

ABSTRACT

Objective To explore the morphological characteristics and differences of posterior malleolus fracture fragments in ankle fracture combined with posterior malleolus fracture and spiral fracture of middle and lower third of tibial combined with posterior malleolus fracture,and to analyze the relationship between the posterior malleolus fracture fragments and the above two types of fracture injury.Methods A retrospective analysis was performed.One hundred patients with ankle fracture were admitted to Beijing Jishuitan Hospital from January 2011 to December 2011,including 59 males and 41 females,aged (42.0 ± 14.1) years,with an age range of 17-73 years.Among them,57 patients who were ankle fracture combined with posterior malleolus fracture were in Group A.Meanwhile,90 patients with spiral fracture of middle and lower third of tibial were admitted to Beijing Jishuitan Hospital from January 2013 to December 2013,including 42 males and 48 females,aged (45.2 ± 13.0) years,with an age range of 18-77 years.Among them,35 patients who were spiral fracture of middle and lower third of tibial combined with posterior malleolus fracture were in group B.A total of 92 patients in the two groups were examined by CT before operation.The patient's fracture classification was determined according to Haraguchi classification.On axial plane,the angle between posterior malleolus fracture line and medial and lateral malleolus axis was defined as Ⅰ a in Haraguchi Ⅰ,angles between posterior malleolus fracture line and medial and lateral malleolus axis were defined as Ⅱ a and H b in Haraguchi Ⅱ,and angle Ⅰ c and Ⅱ c were angles between posterior malleolus fracture line and tibial axis on sagittal CT.Measurement data were expressed as mean ± standard deviation (Mean ± SD).Mann-whitney and Chi-square test were used to compare the differences of different angles in type Ⅰ and type Ⅱ,and whether there were statistical differences in different angles between the two groups.Results In the 92 cases,75 were type Ⅰ,12 were type Ⅱ and 5 were type Ⅲ.The angle of Ⅰ a was (26.6 ± 5.6)°,the angle of Ⅰ c was (15.4 ±4.1)°,the angle of type Ⅱa was (22.1 ±3.3)°,and the angle of Ⅱc was (16.4 ±5.4)°.The difference between Ⅰ a and Ⅱa data was statistically significant (P=0.003),but there was no significant difference between Ⅰ c and Ⅱ c (P =0.667).In group A and group B,the angle of Ⅰ a was (26.6 ± 5.9)°and (26.6±5.1)°,the angle of Ⅰcwas (15.7 ±4.2)°and (14.9±3.9)°,the angle of Ⅱa was (22.0± 3.0)°and (22.2±4.3)°,the angle of Ⅱb was (45.4 ±9.0)°and (46.5 ± 10.0)°,the angle of Ⅱc was (17.0 ±5.4)°and (15.3 ±6.2)°,respectively.There were no significant differences in the angles of Ⅰ a,Ⅰ c,Ⅱ a,Ⅱ b and Ⅱ c between the two groups (P values were 0.862,0.387,1.000,0.932 and 0.444,respectively).Conclusion The posterior malleolar fragments is not associated with fracture type of ankle fracture combined with posterior malleolus frature and the spiral fracture of middle and lower third of tibial combined with posterior malleolus fracture.