title: Automatic Detection of Calcaneal-Fifth Metatarsal Angle Using Radiograph: A Computer-Aided Diagnosis of Flat Foot for Military New Recruits in Taiwan.
abstract: Flatfoot (pes planus) is one of the most important physical examination items for military new recruits in Taiwan. Currently, the diagnosis of flatfoot is mainly based on radiographic examination of the calcaneal-fifth metatarsal (CA-MT5) angle, also known as the arch angle. However, manual measurement of the arch angle is time-consuming and often inconsistent between different examiners. In this study, seventy male military new recruits were studied. Lateral radiographic images of their right and left feet were obtained, and mutual information (MI) registration was used to automatically calculate the arch angle. Images of two critical bones, the calcaneus and the fifth metatarsal bone, were isolated from the lateral radiographs to form reference images, and were then compared with template images to calculate the arch angle. The result of this computer-calculated arch angle was compared with manual measurement results from two radiologists, which showed that our automatic arch angle measurement method had a high consistency. In addition, this method had a high accuracy of 97% and 96% as compared with the measurements of radiologists A and B, respectively. The findings indicated that our MI registration measurement method cannot only accurately measure the CA-MT5 angle, but also saves time and reduces human error. This method can increase the consistency of arch angle measurement and has potential clinical application for the diagnosis of flatfoot.
authors.affiliation: Department of Radiology, Tao Yuan General Hospital, Ministry of Health and Welfare, Taoyuan City, Taiwan; Department of Biomedical Engineering and Environment Science, National Tsing Hua University, Hsinchu City, Taiwan.
authors.forename: Chin-Hua
authors.initials: CH
authors.lastname: Yang
authors.affiliation: Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung City, Taiwan.
authors.forename: Kuei-Ting
authors.initials: KT
authors.lastname: Chou
authors.affiliation: Department of Radiology, Tao Yuan General Hospital, Ministry of Health and Welfare, Taoyuan City, Taiwan.
authors.forename: Mu-Bai
authors.initials: MB
authors.lastname: Chung
authors.affiliation: Department of Biomedical Engineering and Environment Science, National Tsing Hua University, Hsinchu City, Taiwan.
authors.forename: K S
authors.initials: KS
authors.lastname: Chuang
authors.affiliation: Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung City, Taiwan; Department of Biomedical Informatics, Asia University, Taichung City, Taiwan.
authors.forename: Tzung-Chi
authors.initials: TC
authors.lastname: Huang
mesh_terms: D000328:Adult; D000465:Algorithms; D002111:Calcaneus / Q000000981:diagnostic imaging*; D005413:Flatfoot / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D005528:Foot / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008682:Metatarsal Bones / Q000000981:diagnostic imaging*; D008889:Military Personnel; D011857:Radiographic Image Interpretation, Computer-Assisted; D013624:Taiwan; D055815:Young Adult