Normative 3D acetabular orientation measurements by the low-dose EOS imaging system in 102 asymptomatic subjects in standing position: Analyses by side, gender, pelvic incidence and reproducibility

Very precise combined work between multidisciplinary partners (radiation engineers in physics, engineers in biomechanics, medical radiologists and orthopedic pediatric surgeons) has led to the concept and development of a new low-dose radiation device named EOS. This device has three main advantages: (1) Thanks to the invention of Georges Charpak who designed gaseous detectors for X-rays, the reduction of dose necessary to obtain a good image of skeletal system was 8 to 10 times less for 2D imaging; compared to the dose necessary to obtain a 3D reconstruction from CT scan cuts, the reduction factor was 800 to 1000. (2) The accuracy of 3D reconstruction obtained is better than that of 3D reconstruction from CT scan cuts. (3) The patient in addition gets imaged in a standing functional position, thanks to the AP and lateral X-rays obtained from head to feet simultaneously. This is a big advantage compared to CT scans which are used only in lying position. From the simultaneous AP and lateral X-rays of the whole body obtained via the 3D bone external envelop technique, the biomechanics engineers obtain 3D reconstruction of every level of osteo-articular system, especially for spine, in standing position with an acceptable period of time for reconstruction. This (in spite of the evolution of standing MRI) allows more precise bone reconstruction in orthopedics, especially at the level of the entire skeleton, including the head, spine, pelvis, lower limbs, giving new consideration for physiology, physiopathology and therapeutics.

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Relationship between pelvic morphology and functional parameters in standing position for patient-specific cup planning in THA

10.29007/41f9 ◽

2018 ◽

Cited By ~ 1

Author(s):

Maximilian Fischer ◽

Stephanie Schörner ◽

Stefan Rohde ◽

Christian Lüring ◽

Klaus Radermacher

Keyword(s):

Pelvic Tilt ◽

Planning Process ◽

Pelvic Incidence ◽

Pubic Symphysis ◽

Standing Position ◽

Patient Specific ◽

Automatic Process ◽

Sacral Slope ◽

Functional Parameters ◽

Eos Imaging

The sagittal orientation of the pelvis commonly called pelvic tilt has an effect on the orientation of the cup in total hip arthroplasty (THA). Pelvic tilt is different between individuals and changes during activities of daily living. In particular, the pelvic tilt in standing position should be considered during the planning of THA to adapt the target angles of the cup patient-specifically to minimize wear and the risk of dislocation. Methods to measure pelvic tilt require an additional step in the planning process, may be time consuming and additional devices or x-ray imaging are necessary.In this study, the relationship between three functional parameters describing the sagittal pelvic orientation in standing position and seven morphological parameters of the pelvis was investigated. Correlations might be used to estimate the pelvic tilt in standing position by the morphology of the pelvis in order to avoid additional measuring techniques of pelvic tilt in the planning process of THA. For 18 subjects a semi-automatic process was established to match a 3D-reconstruction of the pelvis from CT scans to orthogonal EOS imaging in standing position and to calculate the morphological and functional parameters of the pelvis subsequently.The two strongest correlations of the linear correlation analysis were observed between morphological pelvic incidence and functional sacral slope (r = 0.78; p = 0.0001) and between morphological pubic symphysis-posterior superior iliac spines- ratio and functional tilt of anterior pelvic plane (r = -0.59; p = 0.0098). The results of this study suggest that patient-specific adjustments to the orientation of the cup in planning of THA without additional measurement of the sagittal pelvic orientation in standing position should be based on the correlation between morphological pelvic incidence and functional sacral slope.

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Visual Biofeedback Training Method Using a Photoelastic Imaging System. A Clinical Application for Restoring and Stabilizing a Standing Position of Hemiplegic Patients.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series A ◽

10.1299/kikaia.61.466 ◽

1995 ◽

Vol 61 (582) ◽

pp. 466-471

Author(s):

Hirofumi Nakagawa ◽

Jun-ichi Kitamura ◽

Tohru Kondo ◽

Kazuso Iinuma ◽

Susumu Takahashi

Keyword(s):

Clinical Application ◽

Imaging System ◽

Standing Position ◽

Biofeedback Training ◽

Training Method ◽

Visual Biofeedback ◽

System A

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Sacral incidence to pubis: a novel and alternative morphologic radiological parameter to pelvic incidence in assessing spinopelvic sagittal alignment

BMC Musculoskeletal Disorders ◽

10.1186/s12891-021-04093-z ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Yasuhito Takahashi ◽

Kei Watanabe ◽

Masashi Okamoto ◽

Shun Hatsushikano ◽

Kazuhiro Hasegawa ◽

...

Keyword(s):

Correlation Coefficient ◽

Pelvic Incidence ◽

Sagittal Alignment ◽

Intraclass Correlation ◽

Hip Dislocation ◽

Standing Position ◽

Regression Equation ◽

Whole Body ◽

Spinopelvic Parameters ◽

Pelvic Inclination

Abstract Background Although pelvic incidence (PI) is a key morphologic parameter in assessing spinopelvic sagittal alignment, accurate measurements of PI become difficult in patients with severe hip dislocation or femoral head deformities. This study aimed to investigate the reliability of our novel morphologic parameters and the correlations with established sagittal spinopelvic parameters. Methods One hundred healthy volunteers (25 male and 75 female), with an average age of 38.9 years, were analysed. Whole-body alignment in the standing position was measured using a slot-scanning X-ray imager. We measured the established spinopelvic sagittal parameters and a novel parameter: the sacral incidence to pubis (SIP). The correlation coefficient of each parameter, regression equation of PI using SIP, and regression equation of lumbar lordosis (LL) using PI or SIP were obtained. The intraclass correlation coefficient (ICC) was calculated as an evaluation of the measurement reliability. Results Reliability analysis showed high intra- and inter-rater agreements in all the spinopelvic parameters, with ICCs > 0.9. The SIP and pelvic inclination angle (PIA) demonstrated strong correlation with PI (R = 0.96) and pelvic tilt (PT) (R = 0.92). PI could be predicted according to the regression equation: PI = − 9.92 + 0.905 * SIP (R = 0.9596, p < 0.0001). The ideal LL could be predicted using the following equation using PI and age: ideal LL = 32.33 + 0.623 * PI – 0.280 * age (R = 0.6033, p < 0.001) and using SIP and age: ideal LL = 24.29 + 0.609 * SIP – 0.309 * age (R = 0.6177, p < 0.001). Conclusions Both SIP and PIA were reliable parameters for determining the morphology and orientation of the pelvis, respectively. Ideal LL was accurately predicted using the SIP with equal accuracy as the PI. Our findings will assist clinicians in the assessment of spinopelvic sagittal alignment. Trial registration This study was retrospectively registered with the UMIN Clinical Trials Registry (UMIN000042979; January 13, 2021).

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No linear correlation between pelvic incidence and acetabular orientation

Medicine ◽

10.1097/md.0000000000025445 ◽

2021 ◽

Vol 100 (15) ◽

pp. e25445

Author(s):

Jung-Taek Kim ◽

Quan Hu Shen ◽

Chang-Hoon Jeon ◽

Nam-Su Chung ◽

Seungmin Jeong ◽

...

Keyword(s):

Linear Correlation ◽

Pelvic Incidence ◽

Acetabular Orientation

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EOS Imaging: Low-Dose Imaging and Three-Dimensional Value Along the Entire Patient Care Pathway for Spine and Lower Limb Pathologies

Handbook of Robotic and Image-Guided Surgery ◽

10.1016/b978-0-12-814245-5.00031-1 ◽

2020 ◽

pp. 529-549

Author(s):

Jamie Milas ◽

Mathieu Garayt ◽

Elena Oriot ◽

Joe Hobeika

Keyword(s):

Patient Care ◽

Lower Limb ◽

Low Dose ◽

Care Pathway ◽

Three Dimensional ◽

Eos Imaging ◽

Dose Imaging

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OP45 HTA Of A Pediatric Biplanar Low-Dose X-Ray Imaging System

International Journal of Technology Assessment in Health Care ◽

10.1017/s0266462318000983 ◽

2018 ◽

Vol 34 (S1) ◽

pp. 17-18

Author(s):

Martina Andellini ◽

Francesco Faggiano ◽

Roxana di Mauro ◽

Pietro Derrico ◽

Matteo Ritrovato

Keyword(s):

3D Reconstruction ◽

Low Dose ◽

Imaging System ◽

Weight Bearing ◽

Ct Scanning ◽

Lower Limbs ◽

Final Decision ◽

X Ray ◽

Congenital Deformities ◽

X Ray Imaging

Introduction:Patients with adolescent idiopathic scoliosis frequently receive X-ray imaging at diagnosis and subsequent follow monitoring. To achieve the ALARA concept of radiation dose, a biplanar low-dose X-ray system (BLDS) has been proposed. The aim of the study is to gather evidence on safety, accuracy and overall effectiveness of a BLDS compared with CT scanning, in a pediatric population, in order to support the final decision on possible acquisition of such innovative diagnostic system.Methods:The new method Decision-oriented HTA (DoHTA) was applied to carefully assess the diagnostic technology. It was developed starting from the EUnetHTA Core Model® integrated with the analytic hierarchy process in order to identify all the relevant assessment aspects of the technology involved, identified from scientific literature, experts’ judgments and specific context analysis of Bambino Gesù Children's Hospital. A weight was associated to each assessment element and the alternatives’ ranking was defined.Results:This innovative system provides orthopedic images in standing or sitting position, being able to examine the spine and lower limbs under normal weight-bearing conditions. This system is recommended for particular clinical indications as scoliosis and other congenital deformities of the spine. It is able to acquire simultaneous posteroanterior and lateral images in a single scan without vertical distortion and with lower radiation exposure than CT scanning. 2D images acquired can be combined to obtain a 3D reconstruction scanning based on a semi-automated statistical model.Conclusions:The major advantages of BLDS are the relatively low dose of radiation and the possibility of obtaining a 3D reconstruction of the bones. Our preliminary results show that data on the clinical effectiveness are limited but the technical advancements of BLDS appear promising in terms of patient management and patient health outcomes associated with its use.

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Microdose acquisition in adolescent leg length discrepancy using a low-dose biplane imaging system

Acta Radiologica ◽

10.1177/0284185116682381 ◽

2017 ◽

Vol 58 (9) ◽

pp. 1108-1114 ◽

Cited By ~ 2

Author(s):

Janni Jensen ◽

Bo R Mussmann ◽

John Hjarbæk ◽

Zaid Al-Aubaidi ◽

Niels W Pedersen ◽

...

Keyword(s):

Low Dose ◽

Imaging System ◽

Statistical Significance ◽

Leg Length Discrepancy ◽

Leg Length ◽

Planar Imaging ◽

Length Discrepancy ◽

Significant Difference ◽

Length Measurements ◽

Total Leg

Background Children with leg length discrepancy often undergo repeat imaging. Therefore, every effort to reduce radiation dose is important. Using low dose preview images and noise reduction software rather than diagnostic images for length measurements might contribute to reducing dose. Purpose To compare leg length measurements performed on diagnostic images and low dose preview images both acquired using a low-dose bi-planar imaging system. Material and Methods Preview and diagnostic images from 22 patients were retrospectively collected (14 girls, 8 boys; mean age, 12.8 years; age range, 10–15 years). All images were anonymized and measured independently by two musculoskeletal radiologists. Three sets of measurements were performed on all images; the mechanical axis lines of the femur and the tibia as well as the anatomical line of the entire extremity. Statistical significance was tested with a paired t-test. Results No statistically significant difference was found between measurements performed on the preview and on the diagnostic image. The mean tibial length difference between the observers was −0.06 cm (95% confidence interval [CI], −0.12 to 0.01) and −0.08 cm (95% CI, −0.21 to 0.05), respectively; 0.10 cm (95% CI, 0.02–0.17) and 0.06 cm (95% CI, −0.02 to 0.14) for the femoral measurements and 0.12 cm (95% CI, −0.05 to 0.26) and 0.08 cm (95% CI, −0.02 to 0.19) for total leg length discrepancy. ICCs were >0.99 indicating excellent inter- and intra-rater reliability. Conclusion The data strongly imply that leg length measurements performed on preview images from a low-dose bi-planar imaging system are comparable to measurements performed on diagnostic images.

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