Weight Bearing Cone Beam Computed Tomography (WBCT) in the Foot and Ankle: A Scientific, Technical and Clinical Guide

314 Pages·2020·14.627 MB·English

by  Martinus Richter, Francois Lintz, Cesar de Cesar Netto, Alexej Barg, Arne Burssens, Scott Ellis

Weight Bearing Cone
Beam Computed
Tomography (WBCT)
in the Foot and Ankle
A Scientific, Technical
and Clinical Guide
Martinus Richter
Francois Lintz
Cesar de Cesar Netto
Alexej Barg
Arne Burssens
Scott Ellis
123
Weight Bearing Cone Beam Computed
Tomography (WBCT) in the Foot and Ankle
Martinus Richter • Francois Lintz
Cesar de Cesar Netto • Alexej Barg
Arne Burssens • Scott Ellis
Weight Bearing Cone Beam
Computed Tomography
(WBCT) in the Foot
and Ankle
A Scientific, Technical and Clinical Guide
Martinus Richter Francois Lintz
Department for Foot and Ankle Surgery Foot and Ankle Surgery Centre
Hospital Rummelsberg Clinique de l'Union
Schwarzenbruck Toulouse
Germany France
Cesar de Cesar Netto Alexej Barg
Department of Orthopedics and Rehab University Orthopedic Center
University of Iowa University of Utah
Iowa City, IA Salt Lake City, UT
USA USA
Arne Burssens Scott Ellis
Department of Orthopedics and Trauma Department of Orthopedic Surgery
University Hospital of Ghent Hospital for Special Surgery
Ghent, OVL New York, NY
Belgium USA
ISBN 978-3-030-31948-9 ISBN 978-3-030-31949-6 (eBook)
https://doi.org/10.1007/978-3-030-31949-6
© Springer Nature Switzerland AG 2020
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Preface
Weight bearing cone beam computed tomography (WBCT) was introduced in 2012
for foot and ankle use as a new technology that allows 3D-imaging with full weight
bearing that should be not influenced by projection and/or foot orientation. From the
very beginning of device availability, scientific studies have been employed. In the
early stages of the scientific work-up in different institutions, different methodolo-
gies, especially for the angle measurements, were inaugurated. No standard for the
methodology for the image acquisition and measurement was defined, and different
methods have been published. After ongoing discussion about the optimal approach
for further research in this field, the International WBCT Study Group (WBCT ISG,
www.wbctstudygroup.com) was founded by five investigators from five different
institutions, who are the editors of this book. In the following two years, the group
grew in membership from 5 at the beginning in July 2017 to more than 50 at the end
of 2018. The scientific activities were extraordinary, resulting in 70 PubMed listed
publications dealing with WBCT in foot and ankle at the end of 2018. During the
same period, WBCT ISG organized scientific meetings at different foot and ankle
conferences to spread the acquired knowledge among foot and ankle surgeons.
Based on the fast-growing WBCT ISG and reflecting the increasing importance of
WBCT, the founders of WBCT ISG decided to found the International WBCT
Society (www.wbctsociety.org) and to transfer WBCT ISG into the International
WBCT Society. The society was registered in Belgium and a secretariat was
founded. Since then, the society is further growing and the member number as well
as the number of Pubmed-listed publications by members both reached more than
100 by the end of 2019. The International WBCT Society can be considered as one
of the most scientifically active societies. Meanwhile, the society also inaugurated
educational activities as for example hands-on workshops. At the beginning of
2019, the board of the society discussed how to further spread the knowledge of
WBCT in foot and ankle besides the scientific publications in all relevant scientific
foot and ankle journals and scientific sessions at the most important foot and ankle
conferences. The board then decided to write this book, which should be focused on
v
vi Preface
scientific, technical, clinical, and educational content. In contrast to standard text-
books, the scientific content is emphasized and placed at the beginning to reflect the
initial scientific approach of WBCT ISG and International WBCT Society.
The authors wish that this book serves all current and upcoming users of WBCT
in foot and ankle to answer all scientific and technical questions, to educate and
instruct the clinical use including measurements.
Schwarzenbruck, Germany Martinus Richter, MD, PhD
Toulouse, France Francois Lintz, MD, FEBOT
Iowa City, IA, USA Cesar de Cesar de Netto, MD, PhD
Salt Lake City, UT, USA Alexej Barg, MD
Ghent, OVL, Belgium Arne Burssens, MD
New York, NY, USA Scott Ellis, MD
Contents
Part I H istory and Scientific Overview of Weight Bearing Cone
Beam Computed Tomography
1 Background of Weight Bearing Cone Beam Computed
Tomography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Weight Bearing CT International Study Group (WBCT ISG) . . . . . . . . 6
International WBCT Society . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2 Scientific Overview of Weight Bearing Cone Beam Computed
Tomography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
General Thoughts on Foot and Ankle Imaging . . . . . . . . . . . . . . . . . . . . 9
Studies on Normal Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Studies on Pathologic Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Radiographic Measurements Using Weight Bearing CT . . . . . . . . . . . . 19
Future Directions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Standardization of Measurements Using WBCT . . . . . . . . . . . . . . . . 21
WBCT vs. Plain Films . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Part II S cientific Background of Weight Bearing Cone Beam
Computed Tomography
3 Weight Bearing CT Allows for More Accurate Bone
Position (Angle) Measurement than Radiographs or CT . . . . . . . . . 27
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Inclusion and Exclusion Criteria: Ethics . . . . . . . . . . . . . . . . . . . . . . . 29
Image Acquisition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Time Spent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
vii
viii Contents
Angle Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Time Spent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Angle Measurement: Differences Between Methods . . . . . . . . . . . . . 32
Angle Measurement: Intra- and Interobserver Reliability . . . . . . . . . 32
Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Time Spent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Angle Measurement: Differences between Methods . . . . . . . . . . . . . 33
1st–2nd Intermetatarsal Angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
TMT Dorsoplantar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
TMT Lateral . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Hindfoot Angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Calcaneal Pitch Angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Angle Measurement: Intra- and Interobserver Reliability . . . . . . . . . 35
Shortcomings of the Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Radiation Dose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Cost . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Approval for Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Standard Imaging? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
4 Combination of Weight Bearing CT (WBCT) with Pedography
Shows No Statistical Correlation of Bone Position
with Force/Pressure Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Inclusion and Exclusion Criteria: Ethics . . . . . . . . . . . . . . . . . . . . . . . 43
Image Acquisition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Pedography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Measurements of Bone Position (Angles and Distances) . . . . . . . . . . 44
Measurement of Pedographic Parameters . . . . . . . . . . . . . . . . . . . . . . 46
Correlation Analysis of WBCT Parameters with
Pedography Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Measurements of Bone Position (Angles and Distances):
Intra- and Interobserver Reliability . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Correlation of WBCT Parameters with Pedography Parameters . . . . 48
Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Angle Measurement: Intra- and Interobserver Reliability . . . . . . . . . 50
Correlation of WBCT Parameters with Pedography Parameters . . . . 51
Shortcomings of the Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Radiation Dose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Contents ix
5 Combination of Weight Bearing CT (WBCT) with
Pedography Shows Relationship Between Anatomy-Based
Foot Center (FC) and Force/Pressure-Based Center
of Gravity (COG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Inclusion and Exclusion Criteria, Ethics . . . . . . . . . . . . . . . . . . . . . . . 56
Image Acquisition: Foot Center (FC) . . . . . . . . . . . . . . . . . . . . . . . . . 57
Pedography: Center of Gravity (COG) . . . . . . . . . . . . . . . . . . . . . . . . 57
Comparison of FC/COG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Center of Gravity (COG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Foot Center (FC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Shortcomings of the Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Radiation Dose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
6 A New Concept of 3D Biometrics for Hindfoot Alignment
Using Weight Bearing CT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
Statistical Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
7 3D Biometrics for Hindfoot Alignment Using Weight Bearing
Computed Tomography: A Prospective Assessment of 249 Feet . . . 77
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Materials and Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
Study Population and Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
Patient Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
Statistical Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
8 Relationship Between Chronic Lateral Ankle Instability
and Hindfoot Varus Using Weight Bearing Cone Beam
Computed Tomography: A Retrospective Study . . . . . . . . . . . . . . . . 87
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
Material and Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Study Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Study Population . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
x Contents
Investigations and Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Statistical Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
9 Normal Hindfoot Alignment Assessed by Weight Bearing
CT: Presence of a Constitutional Valgus? . . . . . . . . . . . . . . . . . . . . . . 97
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Materials and Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Study Population and Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Patient Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Statistical Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Hindfoot Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
ROI Density Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
Hindfoot Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
10 Reliability and Correlation Analysis of Computed Methods
to Convert Conventional 2D Radiological Hindfoot
Measurements to 3D Equivalents Using Weight Bearing CT . . . . . . 107
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Materials and Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Study Population, Design, and Measurement Protocol . . . . . . . . . . . 108
Statistical Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Hindfoot Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Ankle and Hindfoot Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
11 The Hind- and Midfoot Alignment Analyzed After a Medializing
Calcaneal Osteotomy Using a 3D Weight Bearing CT . . . . . . . . . . . 121
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Material and Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Study Population, Design, and Measurement Protocol . . . . . . . . . . . 122
Surgical Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
Statistical Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Hindfoot Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Midfoot Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132