Analysis of Normal Ankle Radiographic Angles

Abstract Background Understanding the position of the normal ankle is the key before every successfully surgical planning. The aims of our study were to quantify the normal ankle angles, measures and reference points systematically on ankle radiographs. Methods A total of 900 angles and 300 basic information were measured on 100 healthy ankles. The radiographic measurements were performed on standard weight-bearing anteroposterior (AP) and lateral view of the ankle. A total of 6 angles were made from the AP view, 3 angles from the lateral view. All angles were measured by 2 foot and ankle surgeons, independent of each other. For intraobserver reliability, after six weeks, the same angles were measured by each observer. Results A total of 900 angles and 300 basic information were measured on 100 healthy ankles. The mean age of the subjects was 33.0 ± 9.1years, with 57 females(57%) and 43 males(43%), with 44 left feet(44%) and 56 right feet(56%). Intraobserver is reliability greater than 0.8 and the interobserver reliability greater than 0.8. The following angles were measured from the AP of ankle: TAS’s angle, TT’s angle, TC’s angle, TMM’s angle, TLM’s angle, MA’s angle. The following angles were measured from the lateral view: TLS’s angle, Kite angle, TTA’s angle. Conclusions Our study will provide a set of standard angle measures. The range of angles can be used as a reference for preoperative design and intraoperative and postoperative evaluations.