Open AccessDirect assessment of 3D foot bone kinematics using biplanar X‐ray fluoroscopy and an automatic model registration method
Author(s) -
Ito Kohta,
Hosoda Koh,
Shimizu Masahiro,
Ikemoto Shuhei,
Kume Shinnosuke,
Nagura Takeo,
Imanishi Nobuaki,
Aiso Sadakazu,
Jinzaki Masahiro,
Ogihara Naomichi
Publication year - 2015
Publication title -
journal of foot and ankle research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.763
H-Index - 39
ISSN - 1757-1146
DOI - 10.1186/s13047-015-0079-4
Subject(s) - fluoroscopy , kinematics , translation (biology) , artificial intelligence , rotation (mathematics) , calcaneus , computer vision , computer science , image registration , gait , cadaver , cuboid , medicine , biomedical engineering , anatomy , mathematics , radiology , geometry , image (mathematics) , surgery , physiology , biochemistry , chemistry , physics , classical mechanics , messenger rna , gene
Background Quantifying detailed 3‐dimensional (3D) kinematics of the foot in contact with the ground during locomotion is crucial for understanding the biomechanical functions of the complex musculoskeletal structure of the foot. Biplanar X‐ray fluoroscopic systems and model‐based registration techniques have recently been employed to capture and visualise 3D foot bone movements in vivo , but such techniques have generally been performed manually. In the present study, we developed an automatic model‐registration method with biplanar fluoroscopy for accurate measurement of 3D movements of the skeletal foot. Methods Three‐dimensional surface models of foot bones were generated prior to motion measurement based on computed tomography. The bone models generated were then registered to biplanar fluoroscopic images in a frame‐by‐frame manner using an optimisation technique, to maximise similarity measures between occluding contours of the bone surface models with edge‐enhanced fluoroscopic images, while avoiding mutual penetration of bones. A template‐matching method was also introduced to estimate the amount of bone translation and rotation prior to automatic registration. Results We analysed 3D skeletal movements of a cadaver foot mobilized by a robotic gait simulator. The 3D kinematics of the calcaneus, talus, navicular and cuboid in the stance phase of the gait were successfully reconstructed and quantified using the proposed model‐registration method. The accuracy of bone registration was evaluated as 0.27 ± 0.19 mm and 0.24 ± 0.19° (mean ± standard deviation) in translation and rotation, respectively, under static conditions, and 0.36 ± 0.19 mm and 0.42 ± 0.30° in translation and rotation, respectively, under dynamic conditions. Conclusions The measurement was confirmed to be sufficiently accurate for actual analysis of foot kinematics. The proposed method may serve as an effective tool for understanding the biomechanical function of the human foot during locomotion.