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Garner E, Meynen A, Schey L, Wu J, Zadpoor AA. Automated design of bone-preserving, insertable, and shape-matching patient-specific acetabular components. J Orthop Res 2024. [PMID: 39004739 DOI: 10.1002/jor.25927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 05/15/2024] [Accepted: 06/12/2024] [Indexed: 07/16/2024]
Abstract
Effective treatment of large acetabular defects remains among the most challenging aspects of revision total hip arthroplasty (THA), due to the deficiency of healthy bone stock and degradation of the support columns. Generic uncemented components, which are favored in primary THA, are often unsuitable in revision cases, where the bone-implant contact may be insufficient for fixation, without significant reaming of the limited residual bone. This study presents a computational design strategy for automatically generating patient-specific implants that simultaneously maximize the bone-implant contact area, and minimize bone reaming while ensuring insertability. These components can be manufactured using the same additive manufacturing methods as porous components and may reduce cost and operating-time, compared to existing patient-specific systems. This study compares the performance of implants generated via the proposed method to optimally fitted hemispherical implants, in terms of the achievable bone-implant contact surface, and the volume of reamed bone. Computer-simulated results based on the reconstruction of a set of 15 severe pelvic defects (Paprosky 2A-3B) suggest that the patient-specific components increase bone-implant contact by 63% (median: 63%; SD: 44%; 95% CI: 52.3%-74.0%; RMSD: 42%), and reduce the volume of reamed bone stock by 97% (median: 98%; SD: 4%; 95% CI: 95.9%-97.4%; RMSD: 3.7%).
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Affiliation(s)
- Eric Garner
- Department of Biomechanical Engineering, Delft University of Technology, Delft, The Netherlands
| | - Alexander Meynen
- Department of Development and Regeneration, Faculty of Medicine, Institute for Orthopedic Research and Training (IORT), KU Leuven, Leuven, Belgium
| | - Lennart Schey
- Department of Development and Regeneration, Faculty of Medicine, Institute for Orthopedic Research and Training (IORT), KU Leuven, Leuven, Belgium
| | - Jun Wu
- Department of Sustainable Design Engineering, Delft University of Technology, Delft, The Netherlands
| | - Amir A Zadpoor
- Department of Biomechanical Engineering, Delft University of Technology, Delft, The Netherlands
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2
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Swanepoel HF, Matthews HS, Claes P, Vandermeulen D, Oettlé AC. A statistical shape model for estimating missing soft tissues of the face in a black South African population. J Prosthodont 2024; 33:565-573. [PMID: 37589169 DOI: 10.1111/jopr.13746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 07/30/2023] [Accepted: 08/11/2023] [Indexed: 08/18/2023] Open
Abstract
PURPOSE Facial disfigurement may affect the quality of life of many patients. Facial prostheses are often used as an adjuvant to surgical intervention and may sometimes be the only viable treatment option. Traditional methods for designing soft-tissue facial prostheses are time-consuming and subjective, while existing digital techniques are based on mirroring of contralateral features of the patient, or the use of existing feature templates/models that may not be readily available. We aim to support the objective and semi-automated design of facial prostheses with primary application to midline or bilateral defect restoration where no contralateral features are present. Specifically, we developed and validated a statistical shape model (SSM) for estimating the shape of missing facial soft tissue segments, from any intact parts of the face. MATERIALS AND METHODS An SSM of 3D facial variations was built from meshes extracted from computed tomography and cone beam computed tomography images of a black South African sample (n = 235) without facial disfigurement. Various types of facial defects were simulated, and the missing parts were estimated automatically by a weighted fit of each mesh to the SSM. The estimated regions were compared to the original regions using color maps and root-mean-square (RMS) distances. RESULTS Root mean square errors (RMSE) for defect estimations of one orbit, partial nose, cheek, and lip were all below 1.71 mm. Errors for the full nose, bi-orbital defects, as well as small and large composite defects were between 2.10 and 2.58 mm. Statistically significant associations of age and type of defect with RMSE were observed, but not with sex or imaging modality. CONCLUSION This method can support the objective and semi-automated design of facial prostheses, specifically for defects in the midline, crossing the midline or bilateral defects, by facilitating time-consuming and skill-dependent aspects of prosthesis design.
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Affiliation(s)
| | - Harold S Matthews
- Laboratory for Imaging Genetics, Department of Human Genetics, Katholieke Universiteit, Leuven, Belgium
- Medical Imaging Research Center, Universitair Ziekenhuis, Leuven, Belgium
- Facial Sciences, Murdoch Children's Research Institute, Parkville, Australia
| | - Peter Claes
- Laboratory for Imaging Genetics, Department of Human Genetics, Katholieke Universiteit, Leuven, Belgium
- Medical Imaging Research Center, Universitair Ziekenhuis, Leuven, Belgium
- Facial Sciences, Murdoch Children's Research Institute, Parkville, Australia
- Department of Electrical Engineering, Katholieke Universiteit, Leuven, Belgium
| | - Dirk Vandermeulen
- Medical Imaging Research Center, Universitair Ziekenhuis, Leuven, Belgium
- Department of Electrical Engineering, Katholieke Universiteit, Leuven, Belgium
| | - Anna C Oettlé
- Department of Anatomy, University of Pretoria, Pretoria, South Africa
- Anatomy and Histology Department, Sefako Makgatho Health Sciences University, Pretoria, South Africa
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Grammens J, Van Haver A, Danckaers F, Vuylsteke K, Sijbers J, Mahluf L, Angele P, Kon E, Verdonk P. Three-dimensional bone morphology is a risk factor for medial postmeniscectomy syndrome: A retrospective cohort study. J Exp Orthop 2024; 11:e12090. [PMID: 39035846 PMCID: PMC11260280 DOI: 10.1002/jeo2.12090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Accepted: 06/03/2024] [Indexed: 07/23/2024] Open
Abstract
Purpose The study aims to identify differences in tibiofemoral joint morphology between responders (R group, no pain) to arthroscopic partial medial meniscectomy (APMM) versus medial postmeniscectomy syndrome patients (MPMS group, recurrent pain at 2 years postmeniscectomy) in a clinically neutrally aligned patient population. The second aim was to build a morphology-based predictive algorithm for response to treatment (RTT) in APMM. Methods Two patient groups were identified from a large multicentre database of meniscectomy patients at 2 years of follow-up: the R group included 120 patients with a KOOS pain score > 75, and the MPMS group included 120 patients with a KOOS pain score ≤ 75. Statistical shape models (SSMs) of distal femur, proximal tibia and tibiofemoral joint were used to compare knee morphology. Finally, a predictive model was developed to predict RTT, with the SSM-derived morphologic variables as predictors. Results No differences were found between the R and MPMS groups for patient age, sex, height, weight or cartilage status. Knees in the MPMS group were significantly smaller, had a wider femoral notch and a smaller medial femoral condyle. A morphology-based predictive model was able to predict MPMS at 2 years follow-up with a sensitivity of 74.9% (95% confidence interval [CI]: 74.4%-75.4%) and a specificity of 81.0% (95% CI: 80.6%-81.5%). Conclusion A smaller tibiofemoral joint, a wider intercondylar notch and smaller medial femoral condyle were observed shape variations related to medial postmeniscectomy syndrome. These promising results are a first step towards a knee morphology-based clinical decision support tool for meniscus treatment. Study Design Case-control study. Level of Evidence Level IIIb.
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Affiliation(s)
- Jonas Grammens
- Antwerp Surgical Training, Anatomy and Research CentreUniversity of AntwerpWilrijkBelgium
- imec‐VisionLab, Department of PhysicsUniversity of AntwerpWilrijkBelgium
| | - Annemieke Van Haver
- Antwerp Surgical Training, Anatomy and Research CentreUniversity of AntwerpWilrijkBelgium
- More InstituteDeurneBelgium
| | - Femke Danckaers
- imec‐VisionLab, Department of PhysicsUniversity of AntwerpWilrijkBelgium
| | | | - Jan Sijbers
- imec‐VisionLab, Department of PhysicsUniversity of AntwerpWilrijkBelgium
| | | | - Peter Angele
- Clinic for Trauma and Reconstructive SurgeryUniversity Hospital RegensburgRegensburgGermany
- Sportopaedicum RegensburgRegensburgGermany
| | - Elizaveta Kon
- Humanitas Clinical and Research Center ‐ IRCCSRozzanoMilanItaly
- Department of Biomedical SciencesHumanitas UniversityPieve EmanueleMilanItaly
| | - Peter Verdonk
- Antwerp Surgical Training, Anatomy and Research CentreUniversity of AntwerpWilrijkBelgium
- Department of OrthopaedicsUniversity Hospitals AntwerpEdegemBelgium
- OrthoCAAntwerpBelgium
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Hopkins D, Callary SA, Solomon LB, Woodford SC, Lee PVS, Ackland DC. Computational modeling of revision total hip arthroplasty involving acetabular defects: A systematic review. J Orthop Res 2024. [PMID: 38850264 DOI: 10.1002/jor.25902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 04/22/2024] [Accepted: 05/07/2024] [Indexed: 06/10/2024]
Abstract
Revision total hip arthroplasty (rTHA) involving acetabular defects is a complex procedure associated with lower rates of success than primary THA. Computational modeling has played a key role in surgical planning and prediction of postoperative outcomes following primary THA, but modeling applications in rTHA for acetabular defects remain poorly understood. This study aimed to systematically review the use of computational modeling in acetabular defect classification, implant selection and placement, implant design, and postoperative joint functional performance evaluation following rTHA involving acetabular defects. The databases of Web of Science, Scopus, Medline, Embase, Global Health and Central were searched. Fifty-three relevant articles met the inclusion criteria, and their quality were evaluated using a modified Downs and Black evaluation criteria framework. Manual image segmentation from computed tomography scans, which is time consuming, remains the primary method used to generate 3D models of hip bone; however, statistical shape models, once developed, can be used to estimate pre-defect anatomy rapidly. Finite element modeling, which has been used to estimate bone stresses and strains, and implant micromotion postoperatively, has played a key role in custom and off-the-shelf implant design, mitigation of stress shielding, and prediction of bone remodeling and implant stability. However, model validation is challenging and requires rigorous evaluation and comparison with respect to mid- to long-term clinical outcomes. Development of fast, accurate methods to model acetabular defects, including statistical shape models and artificial neural networks, may ultimately improve uptake of and expand applications in modeling and simulation of rTHA for the research setting and clinic.
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Affiliation(s)
- Daniel Hopkins
- Department of Biomedical Engineering, University of Melbourne, Parkville, Victoria, Australia
| | - Stuart A Callary
- Centre for Orthopaedic and Trauma Research, University of Adelaide, Adelaide, South Australia, Australia
- Department of Orthopaedics and Trauma, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - L B Solomon
- Centre for Orthopaedic and Trauma Research, University of Adelaide, Adelaide, South Australia, Australia
- Department of Orthopaedics and Trauma, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Sarah C Woodford
- Department of Biomedical Engineering, University of Melbourne, Parkville, Victoria, Australia
| | - Peter V S Lee
- Department of Biomedical Engineering, University of Melbourne, Parkville, Victoria, Australia
| | - David C Ackland
- Department of Biomedical Engineering, University of Melbourne, Parkville, Victoria, Australia
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van Veldhuizen WA, van der Wel H, Kuipers HY, Kraeima J, Ten Duis K, Wolterink JM, de Vries JPPM, Schuurmann RCL, IJpma FFA. Development of a Statistical Shape Model and Assessment of Anatomical Shape Variations in the Hemipelvis. J Clin Med 2023; 12:jcm12113767. [PMID: 37297962 DOI: 10.3390/jcm12113767] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 05/28/2023] [Accepted: 05/29/2023] [Indexed: 06/12/2023] Open
Abstract
Knowledge about anatomical shape variations in the pelvis is mandatory for selection, fitting, positioning, and fixation in pelvic surgery. The current knowledge on pelvic shape variation mostly relies on point-to-point measurements on 2D X-ray images and computed tomography (CT) slices. Three-dimensional region-specific assessments of pelvic morphology are scarce. Our aim was to develop a statistical shape model of the hemipelvis to assess anatomical shape variations in the hemipelvis. CT scans of 200 patients (100 male and 100 female) were used to obtain segmentations. An iterative closest point algorithm was performed to register these 3D segmentations, so a principal component analysis (PCA) could be performed, and a statistical shape model (SSM) of the hemipelvis was developed. The first 15 principal components (PCs) described 90% of the total shape variation, and the reconstruction ability of this SSM resulted in a root mean square error of 1.58 (95% CI: 1.53-1.63) mm. In summary, an SSM of the hemipelvis was developed, which describes the shape variations in a Caucasian population and is able to reconstruct an aberrant hemipelvis. Principal component analyses demonstrated that, in a general population, anatomical shape variations were mostly related to differences in the size of the pelvis (e.g., PC1 describes 68% of the total shape variation, which is attributed to size). Differences between the male and female pelvis were most pronounced in the iliac wing and pubic rami regions. These regions are often subject to injuries. Future clinical applications of our newly developed SSM may be relevant for SSM-based semi-automatic virtual reconstruction of a fractured hemipelvis as part of preoperative planning. Lastly, for companies, using our SSM might be interesting in order to assess which sizes of pelvic implants should be produced to provide proper-fitting implants for most of the population.
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Affiliation(s)
| | - Hylke van der Wel
- Department of Oral and Maxillofacial Surgery/3D Lab, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands
| | - Hennie Y Kuipers
- Department of Surgery, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands
| | - Joep Kraeima
- Department of Oral and Maxillofacial Surgery/3D Lab, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands
| | - Kaj Ten Duis
- Department of Surgery, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands
| | - Jelmer M Wolterink
- Department of Applied Mathematics, Technical Medical Centre, 7500 AE Enschede, The Netherlands
| | - Jean-Paul P M de Vries
- Department of Surgery, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands
| | - Richte C L Schuurmann
- Department of Surgery, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands
- Multimodality Medical Imaging Group, Technical Medical Centre, University of Twente, 7500 AE Enschede, The Netherlands
| | - Frank F A IJpma
- Department of Surgery, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands
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Meynen A, Vles G, Roussot M, Van Eemeren A, Wafa H, Mulier M, Scheys L. Advanced quantitative 3D imaging improves the reliability of the classification of acetabular defects. Arch Orthop Trauma Surg 2023; 143:1611-1617. [PMID: 35149888 DOI: 10.1007/s00402-022-04372-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 01/26/2022] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Classifying complex acetabular defects in revision total hip arthroplasty (THA) by means of conventional radiographs comes with significant limitations. Statistical shape modelling allows the virtual reconstruction of the native pelvic morphology, hereby enabling an analytic acetabular defect assessment. Our objective was to evaluate the effect of advanced imaging augmented with analytic representations of the defect on (1) intra- and inter-rater reliability, and (2) up- or downscaling of classification scores when evaluating acetabular defects in patients undergoing revision THA. MATERIALS AND METHODS The acetabular defects of 50 patients undergoing revision THA were evaluated by three independent, fellowship-trained orthopaedic surgeons. Defects were classified according to the acetabular defect classification (ADC) using four different imaging-based representations, namely, standard radiographs, CT imaging, a virtual three-dimensional (3D) model and a quantitative analytic representation of the defect based on a statistical shape model reconstruction. Intra- and inter-rater reliabilities were quantified using Fleiss' and Cohen's kappa scores, respectively. Up- and downscaling of classification scores were compared for each of the imaging-based representations and differences were tested. RESULTS Overall inter-rater agreement across all imaging-based representations for the classification was fair (κ 0.29 95% CI 0.28-0.30). Inter-rater agreement was lowest for radiographs (κ 0.21 95% CI 0.19-0.22) and increased for other representations with agreement being highest when using analytic defect models (κ 0.46 95% CI 0.43-0.48). Overall intra-rater agreement was moderate (κ 0.51 95% CI 0.42-0.60). Intra-rater agreement was lowest for radiographs (κ 0.40 95% CI 0.23-0.57), and highest for ratings including analytic defect models (κ 0.64:95% CI 0.46-0.82). Virtual 3D models with quantitative analytic defect representations upscaled acetabular defect scores in comparison to standard radiographs. CONCLUSIONS Using 3D CT imaging with statistical shape models doubles the intra- and inter-rater reliability and results in upscaling of acetabular defect classification when compared to standard radiographs. This method of evaluating defects will aid in planning surgical reconstruction and stimulate the development of new classification systems based on advanced imaging techniques.
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Affiliation(s)
- Alexander Meynen
- Institute of Orthopaedic Research and Training, Gasthuisberg, University Hospitals Leuven/Catholic University of Leuven, Herestraat 49, 3000, Leuven, Belgium.
| | - Georges Vles
- Institute of Orthopaedic Research and Training, Gasthuisberg, University Hospitals Leuven/Catholic University of Leuven, Herestraat 49, 3000, Leuven, Belgium.,Division of Orthopaedics, Gasthuisberg, University Hospitals Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Mark Roussot
- Department of Trauma and Orthopaedics, University College Hospital London, London, NW1 2BU, UK
| | - Anthony Van Eemeren
- Institute of Orthopaedic Research and Training, Gasthuisberg, University Hospitals Leuven/Catholic University of Leuven, Herestraat 49, 3000, Leuven, Belgium.,Division of Orthopaedics, Gasthuisberg, University Hospitals Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Hazem Wafa
- Institute of Orthopaedic Research and Training, Gasthuisberg, University Hospitals Leuven/Catholic University of Leuven, Herestraat 49, 3000, Leuven, Belgium.,Division of Orthopaedics, Gasthuisberg, University Hospitals Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Michiel Mulier
- Institute of Orthopaedic Research and Training, Gasthuisberg, University Hospitals Leuven/Catholic University of Leuven, Herestraat 49, 3000, Leuven, Belgium.,Division of Orthopaedics, Gasthuisberg, University Hospitals Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Lennart Scheys
- Institute of Orthopaedic Research and Training, Gasthuisberg, University Hospitals Leuven/Catholic University of Leuven, Herestraat 49, 3000, Leuven, Belgium.,Division of Orthopaedics, Gasthuisberg, University Hospitals Leuven, Herestraat 49, 3000, Leuven, Belgium
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7
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Bergiers S, Henckel J, Hothi H, Di Laura A, Goddard C, Raymont D, Ullah F, Cotton R, Bryan R, Hart A. Statistical Shape Modelling the In Vivo Location of Acetabular Wear in Retrieved Hip Implants. BIOENGINEERING (BASEL, SWITZERLAND) 2022; 10:bioengineering10010046. [PMID: 36671617 PMCID: PMC9854783 DOI: 10.3390/bioengineering10010046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 12/19/2022] [Accepted: 12/24/2022] [Indexed: 12/31/2022]
Abstract
Edge-wear in acetabular cups is known to be correlated with greater volumes of material loss; the location of this wear pattern in vivo is less understood. Statistical shape modelling (SSM) may provide further insight into this. This study aimed to identify the most common locations of wear in vivo, by combining CT imaging, retrieval analysis and SMM. Shape variance was described in 20 retrieved metal-on-metal acetabular surfaces. These were revised after a mean of 90 months, from 13 female and seven male patients. They were positioned with a mean inclination and anteversion of 53° and 30°, respectively. Their orientation, in vivo, was established using their stabilising fins, visible in pre-revision CT imaging. The impact of wear volume, positioning, time, gender and size on the in vivo location of wear was investigated. These surfaces had a mean wear volume of 49.63 mm3. The mean acetabular surface displayed superior edge-wear centred 7° within the posterosuperior quadrant, while more of the volumetric wear occurred in the anterosuperior quadrant. Components with higher inclination had greater superior edge-wear scars, while a relationship was observed between greater anteversion angles and more posterosuperior edge-wear. This SSM method can further our understanding of hip implant function, informing future design and may help to refine the safe zone for implant positioning.
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Affiliation(s)
- Sean Bergiers
- Institute of Orthopaedics and Musculoskeletal Science, University College London, London WC1E 6BT, UK
| | - Johann Henckel
- Royal National Orthopaedic Hospital, Stanmore HA7 4LP, UK
| | - Harry Hothi
- Royal National Orthopaedic Hospital, Stanmore HA7 4LP, UK
| | - Anna Di Laura
- Royal National Orthopaedic Hospital, Stanmore HA7 4LP, UK
| | | | | | - Furqan Ullah
- Synopsys Northern Europe Ltd., Exeter EX4 3PL, UK
| | - Ross Cotton
- Synopsys Northern Europe Ltd., Exeter EX4 3PL, UK
| | | | - Alister Hart
- Institute of Orthopaedics and Musculoskeletal Science, University College London, London WC1E 6BT, UK
- Royal National Orthopaedic Hospital, Stanmore HA7 4LP, UK
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Bekkouch IEI, Maksudov B, Kiselev S, Mustafaev T, Vrtovec T, Ibragimov B. Multi-landmark environment analysis with reinforcement learning for pelvic abnormality detection and quantification. Med Image Anal 2022; 78:102417. [PMID: 35325712 DOI: 10.1016/j.media.2022.102417] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 01/14/2022] [Accepted: 03/03/2022] [Indexed: 12/22/2022]
Abstract
Morphological abnormalities of the femoroacetabular (hip) joint are among the most common human musculoskeletal disorders and often develop asymptomatically at early easily treatable stages. In this paper, we propose an automated framework for landmark-based detection and quantification of hip abnormalities from magnetic resonance (MR) images. The framework relies on a novel idea of multi-landmark environment analysis with reinforcement learning. In particular, we merge the concepts of the graphical lasso and Morris sensitivity analysis with deep neural networks to quantitatively estimate the contribution of individual landmark and landmark subgroup locations to the other landmark locations. Convolutional neural networks for image segmentation are utilized to propose the initial landmark locations, and landmark detection is then formulated as a reinforcement learning (RL) problem, where each landmark-agent can adjust its position by observing the local MR image neighborhood and the locations of the most-contributive landmarks. The framework was validated on T1-, T2- and proton density-weighted MR images of 260 patients with the aim to measure the lateral center-edge angle (LCEA), femoral neck-shaft angle (NSA), and the anterior and posterior acetabular sector angles (AASA and PASA) of the hip, and derive the quantitative abnormality metrics from these angles. The framework was successfully tested using the UNet and feature pyramid network (FPN) segmentation architectures for landmark proposal generation, and the deep Q-network (DeepQN), deep deterministic policy gradient (DDPG), twin delayed deep deterministic policy gradient (TD3), and actor-critic policy gradient (A2C) RL networks for landmark position optimization. The resulting overall landmark detection error of 1.5 mm and angle measurement error of 1.4° indicates a superior performance in comparison to existing methods. Moreover, the automatically estimated abnormality labels were in 95% agreement with those generated by an expert radiologist.
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Affiliation(s)
- Imad Eddine Ibrahim Bekkouch
- Sorbonne Center for Artificial Intelligence, Sorbonne University, Paris, France; Institute of Data Science and Artificial Intelligence, Innopolis University, Innopolis, Russia
| | - Bulat Maksudov
- Institute of Data Science and Artificial Intelligence, Innopolis University, Innopolis, Russia; Department of Computer Science, University College Dublin, Dublin, Ireland
| | - Semen Kiselev
- Institute of Data Science and Artificial Intelligence, Innopolis University, Innopolis, Russia
| | - Tamerlan Mustafaev
- Institute of Data Science and Artificial Intelligence, Innopolis University, Innopolis, Russia; Public Hospital #2, Department of Radiology, Kazan, Russia
| | - Tomaž Vrtovec
- Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, Slovenia
| | - Bulat Ibragimov
- Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, Slovenia; Department of Computer Science, University of Copenhagen, Copenhagen, Denmark.
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9
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Meesters AML, Assink N, ten Duis K, Fennema EM, Kraeima J, Witjes MJH, de Vries JPPM, Stirler VMA, IJpma FFA. Accuracy of Patient-Specific Drilling Guides in Acetabular Fracture Surgery: A Human Cadaver Study. J Pers Med 2021; 11:jpm11080763. [PMID: 34442407 PMCID: PMC8400721 DOI: 10.3390/jpm11080763] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 07/26/2021] [Accepted: 07/31/2021] [Indexed: 12/14/2022] Open
Abstract
Due to the complex anatomical shape of the pelvis, screw placement can be challenging in acetabular fracture surgery. This study aims to assess the accuracy of screw placement using patient-specific surgical drilling guides applied to pre-contoured conventional implants in acetabular fracture surgery. CT scans were made of four human cadavers to create 3D models of each (unfractured) pelvis. Implants were pre-contoured on 3D printed pelvic models and optically scanned. Following virtual preoperative planning, surgical drilling guides were designed to fit on top of the implant and were 3D printed. The differences between the pre-planned and actual screw directions (degrees) and screw entry points (mm) were assessed from the pre- and postoperative CT-scans. The median difference between the planned and actual screw direction was 5.9° (IQR: 4–8°) for the in-plate screws and 7.6° (IQR: 6–10°) for the infra-acetabular and column screws. The median entry point differences were 3.6 (IQR: 2–5) mm for the in-plate screws and 2.6 (IQR: 2–3) mm for the infra-acetabular and column screws. No screws penetrated into the hip joint or caused soft tissue injuries. Three-dimensional preoperative planning in combination with surgical guides that envelope pre-contoured conventional implants result in accurate screw placement during acetabular fracture surgery.
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Affiliation(s)
- Anne M. L. Meesters
- Department of Surgery, University Medical Centre Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands; (A.M.L.M.); (N.A.); (K.t.D.); (E.M.F.); (J.-P.P.M.d.V.); (V.M.A.S.)
- 3D Lab, University Medical Centre Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands; (J.K.); (M.J.H.W.)
| | - Nick Assink
- Department of Surgery, University Medical Centre Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands; (A.M.L.M.); (N.A.); (K.t.D.); (E.M.F.); (J.-P.P.M.d.V.); (V.M.A.S.)
- 3D Lab, University Medical Centre Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands; (J.K.); (M.J.H.W.)
| | - Kaj ten Duis
- Department of Surgery, University Medical Centre Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands; (A.M.L.M.); (N.A.); (K.t.D.); (E.M.F.); (J.-P.P.M.d.V.); (V.M.A.S.)
| | - Eelco M. Fennema
- Department of Surgery, University Medical Centre Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands; (A.M.L.M.); (N.A.); (K.t.D.); (E.M.F.); (J.-P.P.M.d.V.); (V.M.A.S.)
| | - Joep Kraeima
- 3D Lab, University Medical Centre Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands; (J.K.); (M.J.H.W.)
- Department of Oral and Maxillofacial Surgery, University Medical Centre Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands
| | - Max J. H. Witjes
- 3D Lab, University Medical Centre Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands; (J.K.); (M.J.H.W.)
- Department of Oral and Maxillofacial Surgery, University Medical Centre Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands
| | - Jean-Paul P. M. de Vries
- Department of Surgery, University Medical Centre Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands; (A.M.L.M.); (N.A.); (K.t.D.); (E.M.F.); (J.-P.P.M.d.V.); (V.M.A.S.)
| | - Vincent M. A. Stirler
- Department of Surgery, University Medical Centre Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands; (A.M.L.M.); (N.A.); (K.t.D.); (E.M.F.); (J.-P.P.M.d.V.); (V.M.A.S.)
| | - Frank F. A. IJpma
- Department of Surgery, University Medical Centre Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands; (A.M.L.M.); (N.A.); (K.t.D.); (E.M.F.); (J.-P.P.M.d.V.); (V.M.A.S.)
- Correspondence: ; Tel.: +31-50-361-6161
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Stochastic PCA-Based Bone Models from Inverse Transform Sampling: Proof of Concept for Mandibles and Proximal Femurs. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11115204] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Principal components analysis is a powerful technique which can be used to reduce data dimensionality. With reference to three-dimensional bone shape models, it can be used to generate an unlimited number of models, defined by thousands of nodes, from a limited (less than twenty) number of scalars. The full procedure has been here described in detail and tested. Two databases were used as input data: the first database comprised 40 mandibles, while the second one comprised 98 proximal femurs. The “average shape” and principal components that were required to cover at least 90% of the whole variance were identified for both bones, as well as the statistical distributions of the respective principal components weights. Fifteen principal components sufficed to describe the mandibular shape, while nine components sufficed to describe the proximal femur morphology. A routine has been set up to generate any number of mandible or proximal femur geometries, according to the actual statistical shape distributions. The set-up procedure can be generalized to any bone shape given a sufficiently large database of the respective 3D shapes.
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