Three-Dimensional Printed Anatomical Models Help in Correcting Foot Alignment in Hallux Valgus Deformities

Category: Basic Sciences/Biologics, Bunion, Midfoot/Forefoot Introduction/Purpose: The progression of the hallux valgus (HV) deformity demonstrates dorsiflexion and abduction; concomitant pronation has not received adequate documentation and the extent of pronation in the pathology is unknown even though correction of the deformity may need to address all three angles. To overcome the inability of standard radiographs to capture pronation, we have developed a means to assess the three dimensional deformity using CT scans. Our goal was to document the extent of pronation/supination both of the first phalanx with respect to the first metatarsal and of the first metatarsal with respect to the second metatarsal. Furthermore, we wanted to regress pronation against the intermetatarsal (IMA) angle of hallux valgus patients. Methods: Three-dimensional models were reconstructed from loaded and unloaded CT files of patients (10 HV, 10 normal). The orientations of specific bones, in anatomic directions, were determined by selecting landmarks on the surface of the phalanx and of the first and second metatarsals. The resulting calculations output a set of angles to determine the pronation/supination of the first metatarsal relative to the second and of the first phalanx relative to the first metatarsal. A regression analysis was conducted to extrapolate any relationship between adduction and pronation (known intermetatarsal and pronation). Results: The average pronation of the first metatarsal relative to the second metatarsal was 19.8 ± 7.1 and 28.3 ± 10.8 in the normal and HV groups respectively (p < 0.05). The influence of weightbearing demonstrated pronation angle differences that were greater in the normal group than in the HV group for both the IM pronation and the HV pronation (p < 0.05) (Figure 1). The differences in HV angles and IM angles between normal and HV patients were 22° and 7° respectively. The regression analysis of the pronation and intermetatarsal angle was not found to be significant, with a weak correlation (r2 = 0.26). Conclusion: The pronation of the first metatarsal relative to the second metatarsal between normal and HV patients is significantly different. While the first metatarsal had measurable pronation in patients with hallux valgus but that value was not predicted by the IMA. The findings of this study indicate pronation should be considered in any surgical technique that seeks to restore native configurations.

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Classification of Hallucal Sesamoid Bone Correlated with Hallux Valgus Severity

BioMed Research International ◽

10.1155/2020/9658916 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Lei Zhang ◽

Junqiu Wang ◽

Jiaju Liu ◽

Jiangqin Luo

Keyword(s):

Hallux Valgus ◽

Statistical Difference ◽

Three Dimensional ◽

Morphological Characteristics ◽

Metatarsophalangeal Joint ◽

Metatarsal Head ◽

Type I ◽

Sesamoid Bone ◽

First Metatarsophalangeal Joint

The hallucal sesamoid bones (HSBs), having an important role in reducing load per unit area on the first metatarsal head, can be injured commonly which also affected the first metatarsophalangeal joint and the surrounding structure. Meanwhile, differences among each HSB type may be a major factor affecting the occurrence and development of HV. So far, many researchers had learned that there are three different conditions in hallucal sesamoid bone affecting the choice of clinical surgery corresponding to different solutions in clinic. Thus, it is necessary to study the anatomical morphological characteristics of the HSB which can be helpful in clinical diagnosis and treatment, especially hallux valgus (HV). 150 X-ray and three-dimensional (3D) computed tomographic (CT) images consist of 72 left and 78 right metatarsals were applied in this anatomic study between two variables and showed by a simple scatter plot. The first metatarsophalangeal joint is divided into four different types: type I (no HSB, 1.3%), type II (with one HSB, 0.07%), type IIIa (with two HSBs when THB is bigger, 28%), type IIIb (with two HSBs when FHB is bigger, 65.3%), and type IV (with three HSBs, 4.7%). There was no statistical difference between the left and right sides, except HVA, Meary, and pitch (P<0.05); all a, b, c, d, and i have statistical difference between male and female (P<0.05). Meanwhile, HVA and IMA and HVA and type group have a significant correlation. In summary, HVA and IMA and HVA and classification of HSBs have significant correlations. The classification and location of HSBs can be an important basis to choose operation methods and postoperation evaluation.

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Sharing and reusing cardiovascular anatomical models over the Web: a step towards the implementation of the virtual physiological human project

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2010.0025 ◽

2010 ◽

Vol 368 (1921) ◽

pp. 3039-3056 ◽

Cited By ~ 23

Author(s):

Daniele Gianni ◽

Steve McKeever ◽

Tommy Yu ◽

Randall Britten ◽

Hervé Delingette ◽

...

Keyword(s):

Three Dimensional ◽

Data Access ◽

Disease Diagnosis ◽

Web Pages ◽

Anatomical Models ◽

Current Sharing ◽

Preliminary Version ◽

Cardiovascular Models ◽

Rendering Engine ◽

The Web

Sharing and reusing anatomical models over the Web offers a significant opportunity to progress the investigation of cardiovascular diseases. However, the current sharing methodology suffers from the limitations of static model delivery (i.e. embedding static links to the models within Web pages) and of a disaggregated view of the model metadata produced by publications and cardiac simulations in isolation. In the context of euHeart—a research project targeting the description and representation of cardiovascular models for disease diagnosis and treatment purposes—we aim to overcome the above limitations with the introduction of euHeartDB, a Web-enabled database for anatomical models of the heart. The database implements a dynamic sharing methodology by managing data access and by tracing all applications. In addition to this, euHeartDB establishes a knowledge link with the physiome model repository by linking geometries to CellML models embedded in the simulation of cardiac behaviour. Furthermore, euHeartDB uses the exFormat—a preliminary version of the interoperable FieldML data format—to effectively promote reuse of anatomical models, and currently incorporates Continuum Mechanics, Image Analysis, Signal Processing and System Identification Graphical User Interface (CMGUI), a rendering engine, to provide three-dimensional graphical views of the models populating the database. Currently, euHeartDB stores 11 cardiac geometries developed within the euHeart project consortium.

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Custom Patient-Specific Three-Dimensional Printed Mitral Valve Models for Pre-Operative Patient Education Enhance Patient Satisfaction and Understanding

Journal of Medical Devices ◽

10.1115/1.4043737 ◽

2019 ◽

Vol 13 (3) ◽

Author(s):

Kay S. Hung ◽

Michael J. Paulsen ◽

Hanjay Wang ◽

Camille Hironaka ◽

Y. Joseph Woo

Keyword(s):

Patient Education ◽

Mitral Valve ◽

Three Dimensional ◽

3D Models ◽

Patient Specific ◽

Imaging Data ◽

Anatomical Models ◽

Mitral Valves ◽

Flexible Polymer ◽

3D Printed

In recent years, advances in medical imaging and three-dimensional (3D) additive manufacturing techniques have increased the use of 3D-printed anatomical models for surgical planning, device design and testing, customization of prostheses, and medical education. Using 3D-printing technology, we generated patient-specific models of mitral valves from their pre-operative cardiac imaging data and utilized these custom models to educate patients about their anatomy, disease, and treatment. Clinical 3D transthoracic and transesophageal echocardiography images were acquired from patients referred for mitral valve repair surgery and segmented using 3D modeling software. Patient-specific mitral valves were 3D-printed using a flexible polymer material to mimic the precise geometry and tissue texture of the relevant anatomy. 3D models were presented to patients at their pre-operative clinic visit and patient education was performed using either the 3D model or the standard anatomic illustrations. Afterward, patients completed questionnaires assessing knowledge and satisfaction. Responses were calculated based on a 1–5 Likert scale and analyzed using a nonparametric Mann–Whitney test. Twelve patients were presented with a patient-specific 3D-printed mitral valve model in addition to standard education materials and twelve patients were presented with only standard educational materials. The mean survey scores were 64.2 (±1.7) and 60.1 (±5.9), respectively (p = 0.008). The use of patient-specific anatomical models positively impacts patient education and satisfaction, and is a feasible method to open new opportunities in precision medicine.

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Impact of Inflow Boundary Conditions on the Calculation of CT-Based FFR

Fluids ◽

10.3390/fluids4020060 ◽

2019 ◽

Vol 4 (2) ◽

pp. 60 ◽

Cited By ~ 2

Author(s):

Ernest Lo ◽

Leon Menezes ◽

Ryo Torii

Keyword(s):

Boundary Conditions ◽

Coronary Arteries ◽

Three Dimensional ◽

Patient Specific ◽

Fractional Flow ◽

Anatomical Models ◽

Diastolic Phase ◽

Flow Reserve ◽

Population Average ◽

The Impact

Background: Calculation of fractional flow reserve (FFR) using computed tomography (CT)-based 3D anatomical models and computational fluid dynamics (CFD) has become a common method to non-invasively assess the functional severity of atherosclerotic narrowing in coronary arteries. We examined the impact of various inflow boundary conditions on computation of FFR to shed light on the requirements for inflow boundary conditions to ensure model representation. Methods: Three-dimensional anatomical models of coronary arteries for four patients with mild to severe stenosis were reconstructed from CT images. FFR and its commonly-used alternatives were derived using the models and CFD. A combination of four types of inflow boundary conditions (BC) was employed: pulsatile, steady, patient-specific and population average. Results: The maximum difference of FFR between pulsatile and steady inflow conditions was 0.02 (2.4%), approximately at a level similar to a reported uncertainty level of clinical FFR measurement (3–4%). The flow with steady BC appeared to represent well the diastolic phase of pulsatile flow, where FFR is measured. Though the difference between patient-specific and population average BCs affected the flow more, the maximum discrepancy of FFR was 0.07 (8.3%), despite the patient-specific inflow of one patient being nearly twice as the population average. Conclusions: In the patients investigated, the type of inflow boundary condition, especially flow pulsatility, does not have a significant impact on computed FFRs in narrowed coronary arteries.

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Hallux Valgus—An Acquired Deformity of the Foot in Cerebral Palsy

Foot & Ankle ◽

10.1177/107110078000100112 ◽

1980 ◽

Vol 1 (1) ◽

pp. 33-38 ◽

Cited By ~ 18

Author(s):

Arthur Holstein

Keyword(s):

Hallux Valgus ◽

Gait Pattern ◽

Valgus Deformity ◽

Lateral Border ◽

Posterior Tibial ◽

Tibial Lengthening ◽

Below The Knee ◽

Hallux Valgus Deformity ◽

The One ◽

Foot Alignment

In this series, acquired hallux valgus deformity occurred in those cerebral palsied children who, when initially seen as prewalkers, had neutral foot alignment and then developed a stance and gait pattern of flexion-adduction at the hips, flexion at the knees, and equinus of the feet, with external torsional effect in the leg below the knee forcing the foot into relative equinovalgus. This resulted in an abducted forefoot manifested primarily as a hallux valgus. The one variation to this premise was the equinovarus heel and adducted forefoot. Here, the resultant thrust was on the lateral border of the foot, and hallux valgus did not occur. In all instances where the response to surgery is incomplete, the foot deformity will develop. Finally, it is noted that a posterior tibial lengthening added to the surgical procedures done for the equinovarus foot has the potential ability in the cerebral palsied child to convert an equinovarus, which does not produce an acquired hallux valgus, into equinovalgus, which does produce this deformity.

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Etiological factors in hallux valgus, a three-dimensional analysis of the first metatarsal

Journal of Foot and Ankle Research ◽

10.1186/s13047-017-0226-1 ◽

2017 ◽

Vol 10 (1) ◽

Cited By ~ 9

Author(s):

Tomohiko Ota ◽

Takeo Nagura ◽

Tetsuro Kokubo ◽

Masateru Kitashiro ◽

Naomichi Ogihara ◽

...

Keyword(s):

Hallux Valgus ◽

Dimensional Analysis ◽

Three Dimensional ◽

Etiological Factors ◽

First Metatarsal

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3D PRINTING TECHNOLOGY IN HUMAN ANATOMY MODERN TEACHING AND LEARNING

SOCIETY INTEGRATION EDUCATION Proceedings of the International Scientific Conference ◽

10.17770/sie2019vol1.3713 ◽

2019 ◽

Vol 1 ◽

pp. 234

Author(s):

Dzintra Kazoka ◽

Mara Pilmane

Keyword(s):

3D Printing ◽

Teaching And Learning ◽

Three Dimensional ◽

Human Anatomy ◽

Anatomical Models ◽

Printing Technology ◽

3D Printing Technology ◽

Medical Study ◽

Study Process ◽

Teaching Learning

There are various combinations of 3D printing technology and medical study process. The aim of this study was to summarize our first experience on 3D printing and outline how 3D printed models can be successfully used in Human Anatomy modern teaching and learning. In 2018 autumn semester, together with traditional methods, a three-dimensional (3D) printing has been introduced into Human Anatomy curriculum at Department of Morphology. In practical classes 39 groups of students from Faculty of Medicine 1st year together with 3 tutors used 3 different open source softwares to create anatomical models and prepared them for printing process. All anatomical models were produced using an FDM 3D printer, a Prusa i3 MK2 (Prusa Research). As methods for data collection were used our observational notes during teaching and learning, analysis of discussions between tutors and students, comments on the preparing and usability of the created and printed models. 3D printing technology offered students a powerful tool for their teaching, learning and creativity, provided possibility to show human body structures or variations. Presented data offered valuable information about current situation and these results were suitable for the further development of the Human Anatomy study course.

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The Effect of Walking Speed on Foot Kinematics is Modified When Increased Pronation is Induced

Journal of the American Podiatric Medical Association ◽

10.7547/15-120 ◽

2016 ◽

Vol 106 (6) ◽

pp. 419-426 ◽

Cited By ~ 3

Author(s):

Joana F. Hornestam ◽

Thales R. Souza ◽

Paula Arantes ◽

Juliana Ocarino ◽

Paula L. Silva

Keyword(s):

Walking Speed ◽

Three Dimensional ◽

Frontal Plane ◽

Foot Kinematics ◽

Functional Strategy ◽

Foot Motion ◽

Clinical Consequences ◽

System Data ◽

Analysis System ◽

Foot Alignment

Background: The relation between walking speed and foot kinematics during gait is not well established, and neither is it clear whether this relation is modified in the presence of factors expected to increase pronation (eg, abnormal foot alignment). Understanding how foot kinematics is affected by walking speed under varying conditions could contribute to our understanding of stresses to the musculoskeletal system during walking. We evaluated the effect of walking speed on foot kinematics in the frontal plane during gait and determined whether this effect is modified by using medially inclined insoles that force the foot into increased pronation. Methods: Twenty-six healthy young adults were assessed while walking on a treadmill wearing flat insoles and wearing medially inclined insoles. Foot kinematics in the frontal plane was measured with a three-dimensional motion analysis system. Data were analyzed during the stance phase of gait. Results: There was no main effect of speed on average calcaneal position. However, there was a significant insole type × walking speed interaction effect. In the flat insole condition, increased walking speed was associated with a less inverted average calcaneal position (or greater magnitudes of eversion), whereas in the inclined insole condition, higher speeds were associated with a less everted average calcaneal position (or increased magnitudes of inversion). Conclusions: The magnitude of foot eversion increases at faster gait speeds under typical conditions. In the presence of factors that induce excessive pronation, however, this effect is reversed. Results suggest that individuals use greater active control of foot motion at faster speeds in the presence of excessive pronation to improve push-off efficiency. Potential clinical consequences of this functional strategy are discussed.

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