Statistical Shape Model-Based Femur Kinematics From Biplane Fluoroscopy

Nora Baka, Marleen de Bruijne, Theo van Walsum, BL Kaptein, JE Giphart, Michiel Schaap, Wiro Niessen, BPF Lelieveldt

Research output: Contribution to journalArticleAcademicpeer-review

20 Citations (Scopus)

Abstract

Studying joint kinematics is of interest to improve prosthesis design and to characterize postoperative motion. State of the art techniques register bones segmented from prior computed tomography or magnetic resonance scans with X-ray fluoroscopic sequences. Elimination of the prior 3D acquisition could potentially lower costs and radiation dose. Therefore, we propose to substitute the segmented bone surface with a statistical shape model based estimate. A dedicated dynamic reconstruction and tracking algorithm was developed estimating the shape based on all frames, and pose per frame. The algorithm minimizes the difference between the projected bone contour and image edges. To increase robustness, we employ a dynamic prior, image features, and prior knowledge about bone edge appearances. This enables tracking and reconstruction from a single initial pose per sequence. We evaluated our method on the distal femur using eight biplane fluoroscopic drop-landing sequences. The proposed dynamic prior and features increased the convergence rate of the reconstruction from 71% to 91%, using a convergence limit of 3 mm. The achieved root mean square point-to-surface accuracy at the converged frames was 1.48 +/- 0.41 mm. The resulting tracking precision was 1-1.5 mm, with the largest errors occurring in the rotation around the femoral shaft (about 2.5 degrees precision).
Original languageUndefined/Unknown
Pages (from-to)1573-1583
Number of pages11
JournalIEEE Transactions on Medical Imaging
Volume31
Issue number8
DOIs
Publication statusPublished - 2012

Cite this