Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Aug 23.
doi: 10.1007/s10439-025-03831-x. Online ahead of print.

Accuracy and Reliability of Synthetic Computed Tomography for Model-Based Tracking of Biplane Videoradiography Data

Seth J Kussow  1   2 , Jared L Zitnay  1 , Penny R Atkins  3 , Andrew E Anderson  4   5   6   7
Affiliations

Accuracy and Reliability of Synthetic Computed Tomography for Model-Based Tracking of Biplane Videoradiography Data

Seth J Kussow et al. Ann Biomed Eng. .

Abstract

Purpose: Biplane videoradiography (BVR) accurately measures hip kinematics in vivo. One downside of BVR is that it typically requires a pelvic computed tomography (CT) scan to reconstruct surfaces for model-based tracking (MBT), increasing the radiation burden to participants. Synthetic CT (sCT) from magnetic resonance imaging (MRI) provides similar volumetric image-based data. The purpose of this study was to assess the effect sCT has on the accuracy and reliability of in vivo hip kinematics from BVR data.

Methods: Three asymptomatic participants received CT and MRI scans and were imaged with BVR while standing and during gait. Kinematics were calculated from femur and pelvis surfaces reconstructed from CT and sCT scans. Accuracy and inter-/intra-reviewer reliability of hip kinematics using sCT were assessed against CT as the reference using mean absolute error (MAE), mean difference (MD), precision, and inter-/intra-class correlation coefficients (ICCs). Kinematics were represented with and without correction for standing posture.

Results: MAE, MD, and precision of posture-corrected sCT kinematic results were 0.85, 0.60, and 0.71° for rotations and 0.40, 0.23, and 0.39 mm for translations, respectively. Accuracy of posture-corrected joint angles was within 0.17° of prior MBT validation in the hip, while translation accuracy and precision were greater herein. Kinematic results using CT and sCT had similar reliability.

Conclusion: The results of this study establish novel reliability metrics for in vivo hip kinematics from BVR. Findings indicate that sCT can be used in lieu of CT to measure in vivo hip kinematics, reducing radiation burden of BVR hip kinematic protocols by up to 73%.

Keywords: Bone-to-bone distance; Hip kinematics; Limits of agreement; Magnetic resonance imaging; Radiation-free; Repeatability.

PubMed Disclaimer

Conflict of interest statement

Declarations. Conflict of interest: The authors report no financial conflicts of interest in regard to the research reported herein. Ethical Approval: This study and consent materials were approved by the University of Utah Institutional Review Board (IRB #51053) and the procedures conducted adhere to the 1964 Declaration of Helsinki. Informed Consent: Participants in this study provided voluntary informed consent to participate in this research.

References

    1. Kapron, A. L., S. K. Aoki, C. L. Peters, S. A. Maas, M. J. Bey, R. Zauel, and A. E. Anderson. Accuracy and feasibility of dual fluoroscopy and model-based tracking to quantify in vivo hip kinematics during clinical exams. J. Appl. Biomech. 2014. https://doi.org/10.1123/jab.2013-0112 . - DOI - PubMed - PMC
    1. Lin, H., S. Wang, T.-Y. Tsai, G. Li, and Y.-M. Kwon. In vitro validation of a non-invasive dual fluoroscopic imaging technique for measurement of the hip kinematics. Med. Eng. Phys. 2013. https://doi.org/10.1016/j.medengphy.2012.10.004 . - DOI - PubMed
    1. Martin, D. E., N. J. Greco, B. A. Klatt, V. J. Wright, W. J. Anderst, and S. Tashman. Model-based tracking of the hip: implications for novel analyses of hip pathology. J. Arthroplasty. 2011. https://doi.org/10.1016/j.arth.2009.12.004 . - DOI - PubMed
    1. Atkins, P. R., N. M. Fiorentino, and A. E. Anderson. In vivo quantification of hip arthrokinematics during dynamic weight-bearing activities using dual fluoroscopy. J. Vis. Exp. 2021. https://doi.org/10.3791/62792 . - DOI - PubMed
    1. Bey, M. J., R. Zauel, S. K. Brock, and S. Tashman. Validation of a new model-based tracking technique for measuring three-dimensional, in vivo glenohumeral joint kinematics. J. Biomech. Eng. 2006. https://doi.org/10.1115/1.2206199 . - DOI - PubMed

LinkOut - more resources