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Cao H, Sesselmann S, Xu J, Seehaus F, Forst R. How Do Classic (Static) RSA and Patient Motion Artifacts Affect the Assessment of Migration of a TKA Tibial Component? An In Vitro Study. Clin Orthop Relat Res 2023; 481:400-412. [PMID: 36398327 PMCID: PMC9831201 DOI: 10.1097/corr.0000000000002453] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 09/21/2022] [Indexed: 11/21/2022]
Abstract
BACKGROUND Classic (static) Roentgen stereophotogrammetric analysis (RSA) is the current gold standard to assess, in vivo, the migration of total joint arthroplasty components. To prevent potential patient motion artifacts during the acquisition of paired radiostereometric images, images must be taken by simultaneously firing both X-ray tubes. However, the influence of nonsynchronized RSA paired images or patient motion artifacts on the precision of RSA and the assessment of implant migration is not well understood. QUESTIONS/PURPOSES We assessed (1) the effect of possible patient motion on the precision of RSA and (2) apparent differences in implant migration among axes (in-plane and out-of-plane translations and in-plane and out-of-plane rotations) of possible motion artifacts. METHODS Radiographs of two tibial knee arthroplasty components, each fixed in two bone-implant models as a customized phantom, were taken in a uniplanar measurement setup. We evaluated both model-based (implant models from reversed engineering) and marker-based (additional attached implant markers) RSA approaches. Between the simulated reference and follow-up examinations, we used one of the bone-implant models to simulate patient motion and the other to simulate no patient motion in parallel. Two defined protocols were followed for each of the bone-implant models: no-motion and simulated motion protocols. RSA image pairs were analyzed using a model-based RSA software package (MBRSA 4.1, RSA core ). Precision was calculated through repeat examinations, and migration of the two components was assessed for comparison of the components with each other. Measurements were taken along the medial-lateral and posterior-anterior axes for translations and around the cranial-caudal axis for rotations. The maximum total point motion was measured for comparison between the two components. RESULTS The effect of simulated patient motion was generally small, except in the cranial-caudal axis, but the induced imprecision associated with motion was larger in model-based RSA than it was in marker-based RSA. The mean ± standard deviation values of precision in model-based RSA were 0.035 ± 0.015 mm, 0.045 ± 0.014 mm, and 0.049 ± 0.036 mm greater than those in marker-based RSA, in accordance with the simulated motion protocol in translations along the medial-lateral axis (0.018 ± 0.004 mm; p = 0.01), along the posterior-anterior axis (0.018 ± 0.007 mm; p = 0.003), and rotations around the cranial-caudal axis (0.017 ± 0.006 mm; p = 0.02). Apparent differences in implant migration were the greatest for the maximum total point motion. The maximum total point motion increased from 0.038 ± 0.007 mm for the no-motion protocol to 1.684 ± 0.038 mm (p < 0.001) for the simulated motion protocol in marker-based RSA, and from 0.101 ± 0.027 mm for the no-motion protocol to 1.973 ± 0.442 mm (p < 0.001) for the simulated motion protocol in model-based RSA, and was the worst-case scenario regarding patient motion artifacts. CONCLUSION Patient motion exceeding 1 mm or 1° on nonsynchronized RSA images affects measurement errors regarding the detection of migration of a tibial component. In clinical RSA studies, the effect of patient motion on the assessment of implant migration should be of particular concern, even if clinical RSA systems have acceptable precision. Specially trained radiographers are crucial for correctly acquiring radiographs, especially when simultaneous radiography exposures are not electronically automated. In general, RSA requires synchronized image acquisition, and this should be the state-of-the-art. CLINICAL RELEVANCE In clinical RSA studies, precision assessed by repeat examinations may not be reliable using the current standards that are widely used in radiology departments. When assessing implant migration for reliability, comparison of the maximum total point motion between the tested (simulated motion) implant and baseline (no-motion) implant, as in this study, is advocated because of the accurate detection of patient motion artifacts.
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Affiliation(s)
- Han Cao
- Department of Orthopaedic Surgery, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
- Department of Orthopaedic Surgery, Taizhou Second People’s Hospital, Taizhou, PR China
| | - Stefan Sesselmann
- Institute for Medical Technology, Ostbayerische Technische Hochschule Amberg-Weiden, Weiden, Germany
| | - Jing Xu
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, PR China
| | - Frank Seehaus
- Department of Orthopaedic Surgery, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
- Department of Orthopaedic and Trauma Surgery, University Hospital Erlangen, Erlangen, Germany
| | - Raimund Forst
- Department of Orthopaedic Surgery, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
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Cao H. Accuracy of radiostereometric analysis using a motorized Roentgen system in a pilot study for clinical simulation. Med Eng Phys 2023; 111:103929. [PMID: 36792244 DOI: 10.1016/j.medengphy.2022.103929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 10/26/2022] [Accepted: 11/21/2022] [Indexed: 11/25/2022]
Abstract
Radiostereometric analysis (RSA) is routinely implemented with two paired Roentgen tubes for three-dimensional (3D) implant migration measurements. A conventional set-up of one stationary tube and one mobile could be time-consuming. Utilizing two customized ceiling-mounted tubes is normally associated with investment costs. Thus, a pilot set-up of a motorized system (single Roentgen source) for radiostereometric image acquisition may be a time-saving and space-efficient alternative. RSA using the motorized system is feasible in this study as a non-synchronized image acquisition technique, however, patient motion may occur and influence the assessment of implant migration. The phantom study aimed to assess accuracy of RSA using the motorized Roentgen system in this in vitro study. Accuracy values of translations and rotations were ±0.29 mm and ±0.48° for the single Roentgen source RSA set-up and ±0.26 mm and ±0.48° for the conventional RSA set-up. This study was also performed to simulate potential patient motion during exposure intervals between paired image acquisition. RSA using the motorized system is able to implement RSA with acceptable accuracy. In general, RSA with synchronized image acquisition is the gold standard to access in vivo implant migration with the highest accuracy. Patient motion exists in non-synchronized image acquisition techniques and results in RSA-related motion artifacts. Then we introduced what RSA-related motion artifacts are. The uniplanar calibration cage applied in the study has a few fiducial and control markers, and some of the markers were occluded in radiographs. Whereas, the number of markers in the calibration cage is correlated with accuracy of 3D implant reconstruction.
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Affiliation(s)
- Han Cao
- Department of Orthopaedic Surgery, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany; Department of Orthopaedic Surgery, Taizhou Second People's Hospital, 225599 Taizhou, China.
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Jürgens-Lahnstein JH, Petersen ET, Laursen M, Hauskov Iversen C, Kaptein BL, Lindgren L, Stilling M. Development, construction, and validation of a thinner uniplanar calibration cage for radiostereometry. J Orthop Res 2022; 40:1645-1653. [PMID: 34664740 DOI: 10.1002/jor.25193] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 09/15/2021] [Accepted: 09/30/2021] [Indexed: 02/04/2023]
Abstract
Radiostereometric analysis (RSA) is an accurate and precise radiographic method that can be used to measure micromotion of implants and study joint kinematics in vivo. A calibration cage with radiopaque markers is used to calibrate the RSA images; however, the thickness (250 mm) of the calibration cage restricts the available area for the patient and equipment during RSA recordings. A thinner calibration cage would increase the recording area, facilitate handling of the cage, and ease integration of the cage with the RSA system. We developed a thinner calibration cage without compromise of accuracy and precision. First, we performed numerical simulations of an RSA system, and showed that the calibration cage thickness could be decreased to 140 mm maintaining accuracy and precision using 40 fiducial and 30 control markers. Second, we constructed a new calibration cage (NRT cage) according to the simulation results. Third, we validated the new calibration cage against two state-of-the-art calibration cages (Umeaa cage and Leiden cage) in a phantom study. All cages performed similar for marker-based analysis, except for y-rotation, where the Umeaa cage (SD = 0.064 mm) was less precise compared to the NRT (SD = 0.038 mm) and Leiden cages (0.042 mm) (p = .01). For model-based analysis the NRT cage had superior precision for translations (SD ≤ 0.054 mm) over the Leiden cage (SD ≤ 0.118 mm) and Umeaa cage (SD ≤ 0.093 mm) (p < .01). The combined study confirmed that the new and thinner calibration cage maintained accuracy and precision at the level of existing thicker calibration cages.
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Affiliation(s)
| | - Emil Toft Petersen
- Department of Orthopaedics, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Mogens Laursen
- Department of Orthopaedics, Aalborg University Hospital, Aalborg, Denmark
| | | | - Bart L Kaptein
- Department of Orthopaedics, Leiden University Medical Center, Leiden, The Netherlands
| | - Lars Lindgren
- Department of Radiology, Aarhus University Hospital, Aarhus, Denmark
| | - Maiken Stilling
- Department of Orthopaedics, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
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Projective geometric model for automatic determination of X-ray-emitting source of a standard radiographic system. Comput Biol Med 2018; 99:209-220. [PMID: 29957378 DOI: 10.1016/j.compbiomed.2018.06.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 06/04/2018] [Accepted: 06/17/2018] [Indexed: 01/14/2023]
Abstract
BACKGROUND AND OBJECTIVE Currently, many orthopedic operations are planned by analyzing X-rays. The exact position of the focus is needed to calculate the real size of an object that is represented in conical projection, although in practice, this position is difficult to determine using current X-ray commercial systems. In this paper, a new geometric model is proposed in order to determine accurately, practically, and economically the location of the emitting source of commercial imaging systems using a single standard X-ray image. METHOD The method requires a specific reference locator object to be positioned in the visual field of radiographic image. Because this object cannot implement ideal geometric points, but instead works with small spheres, it was necessary to experimentally validate the proposed methodology. The implemented software that was developed to validate the model was used in four series of tests. In these tests, we studied the influence on the final result of: 1. the selection of a specific set of markers in radiography, 2. the focus position variation in relation to radiograph and 3. the possible rotated angle of locator object about Z axis. RESULTS The results for 164 tests that were performed with this software showed that the expected error for 99.5% of values ranges with maximum error of [-0.35%, +0.39%], which shows that the model is independent of the design of locator object and its position and orientation in the radiographic field. The software used to validate the proposed model has been found useful to verify its reliability, effectiveness, ease of implementation, and accuracy. CONCLUSIONS This model is effective to calculate the precise position of the X-ray focus of any standard radiographic system accurately.
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Broberg JS, Yuan X, Teeter MG. Radiostereometric analysis using clinical radiographic views: Development of a universal calibration object. J Biomech 2018; 73:238-242. [PMID: 29628133 DOI: 10.1016/j.jbiomech.2018.03.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 02/14/2018] [Accepted: 03/21/2018] [Indexed: 11/24/2022]
Abstract
Radiostereometric analysis (RSA) is a highly accurate technique used to provide three-dimensional (3D) measurements of orthopaedic implant migration for clinical research applications, yet its implementation in routine clinical examinations has been limited. Previous studies have introduced a modified RSA procedure that separates the calibration examinations from the patient examinations, allowing routine clinical radiographs to be analyzed using RSA. However, in order to calibrate the wide range of clinical views, a new calibration object is required. In this study, a universal, isotropic calibration object was designed to calibrate any pair of radiographic views used in the clinic for RSA. A numerical simulation technique was used to design the calibration object, followed by a phantom validation test of a prototype to verify the performance of the novel object, and to compare the measurement reliability to the conventional calibration cage. The 3D bias for the modified calibration method using the new calibration object was 0.032 ± 0.006 mm, the 3D repeatability standard deviation was 0.015 mm, and the 3D repeatability limit was 0.042 mm. Although statistical differences were present between the universal calibration object and the conventional cage, the differences were considered to be not clinically meaningful. The 3D bias and repeatability values obtained using the universal calibration object were well under the threshold acceptable for RSA, therefore it was successfully validated. The universal calibration object will help further the adoption of RSA into a more routine practice, providing the opportunity to generate quantitative databases on joint replacement performance.
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Affiliation(s)
- Jordan S Broberg
- Department of Medical Biophysics, Schulich School of Medicine & Dentistry, Western University, Canada
| | - Xunhua Yuan
- Imaging Research Laboratories, Robarts Research Institute, Schulich School of Medicine & Dentistry, Western University, Canada.
| | - Matthew G Teeter
- Department of Medical Biophysics, Schulich School of Medicine & Dentistry, Western University, Canada; Imaging Research Laboratories, Robarts Research Institute, Schulich School of Medicine & Dentistry, Western University, Canada; Division of Orthopaedic Surgery, Department of Surgery, Schulich School of Medicine & Dentistry, Western University, Canada; Surgical Innovation Program, Lawson Health Research Institute, Canada
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6
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Van de Kleut ML, Yuan X, Athwal GS, Teeter MG. Validation of radiostereometric analysis in six degrees of freedom for use with reverse total shoulder arthroplasty. J Biomech 2018; 68:126-131. [DOI: 10.1016/j.jbiomech.2017.12.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 12/11/2017] [Accepted: 12/17/2017] [Indexed: 11/15/2022]
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Abstract
STUDY DESIGN Systematic review of literature. OBJECTIVES This systematic review was conducted to investigate the accuracy of radiostereometric analysis (RSA), its assessment of spinal motion and disorders, and to investigate the limitations of this technique in spine assessment. METHODS Systematic review in all current literature to invesigate the role of RSA in spine. RESULTS The results of this review concluded that RSA is a very powerful tool to detect small changes between 2 rigid bodies such as a vertebral segment. The technique is described for animal and human studies for cervical and lumbar spine and can be used to analyze range of motion, inducible displacement, and fusion of segments. However, there are a few disadvantages with the technique; RSA percutaneous procedure needs to be performed to implant the markers (and cannot be used preoperatively), one needs a specific knowledge to handle data and interpret the results, and is relatively time consuming and expensive. CONCLUSIONS RSA should be looked at as a very powerful research instrument and there are many questions suitable for RSA studies.
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Affiliation(s)
- Ali Humadi
- The Alfred Hospital, Melbourne, Victoria, Australia,Ali Humadi, Department of Orthopaedics and Trauma, The Alfred Hospital, 55 Commercial Road, Melbourne, Victoria 3004, Australia.
| | - Sulaf Dawood
- The Alfred Hospital, Melbourne, Victoria, Australia,Ali Humadi, Department of Orthopaedics and Trauma, The Alfred Hospital, 55 Commercial Road, Melbourne, Victoria 3004, Australia.
| | - Klas Halldin
- Sahlgrenska University Hospital, Gothenburg, Sweden,Ali Humadi, Department of Orthopaedics and Trauma, The Alfred Hospital, 55 Commercial Road, Melbourne, Victoria 3004, Australia.
| | - Brian Freeman
- Royal Adelaide Hospital, Adelaide, SA, Australia,Ali Humadi, Department of Orthopaedics and Trauma, The Alfred Hospital, 55 Commercial Road, Melbourne, Victoria 3004, Australia.
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8
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Lam-Tin-Cheung K, Yuan X, Nikolov HN, Lanting BA, Naudie DD, Teeter MG. Marker-based technique for visualizing radiolucent implant components in radiographic imaging. J Orthop Res 2017; 35:2017-2022. [PMID: 27859535 DOI: 10.1002/jor.23475] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 11/03/2016] [Indexed: 02/04/2023]
Abstract
Radiography is the predominant imaging modality used for the in-vivo analysis of orthopaedic implants. A major disadvantage of radiography is that the articulating joint components that are composed of radiolucent polyethylene cannot be directly visualized. Current strategies attempt to circumvent this limitation by estimating component positions and simplifying the joint system, however, these approaches lead to a number of associated errors. Thus, this study provides a method to enable the visualization of the polyethylene component of total knee replacements in radiographic images. This was achieved through the repeatable insertion of markers and accompanying registration process, which were evaluated in this study for reproducibility and accuracy. An insertion guide was developed to insert tantalum beads into polyethylene tibial surface liners. The bead-inserted liners were micro-CT scanned to obtain 3D surface geometries. An in-vivo mimicking phantom RSA experiment was then used to test the 3D to 2D registration process. The guide positioned the beads consistently to ±0.21 mm. The 3D to 2D registration demonstrated a repeatability of -0.014 ± 0.008 mm. Registration of different bead-inserted tibial liners to the phantom revealed an average error of 0.026 ± 0.047 mm for this visualization method. This visualization approach provides greatly improved registration and inter-component measurements than current alternative strategies. This process is suitable for a number of other joints and would greatly benefit procedures that analyze component interactions and implant performance over time. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2017-2022, 2017.
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Affiliation(s)
- Kimberley Lam-Tin-Cheung
- Department of Medical Biophysics, Schulich School of Medicine and Dentistry, Western University, 1151 Richmond Street, London, N6A 3K7, Ontario, Canada
| | - Xunhua Yuan
- Imaging Research Laboratories, Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, 1151 Richmond St. N., London, N6A 5B7, Ontario, Canada
| | - Hristo N Nikolov
- Imaging Research Laboratories, Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, 1151 Richmond St. N., London, N6A 5B7, Ontario, Canada
| | - Brent A Lanting
- Division of Orthopaedic Surgery, Department of Surgery, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Douglas D Naudie
- Division of Orthopaedic Surgery, Department of Surgery, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Matthew G Teeter
- Department of Medical Biophysics, Schulich School of Medicine and Dentistry, Western University, 1151 Richmond Street, London, N6A 3K7, Ontario, Canada.,Imaging Research Laboratories, Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, 1151 Richmond St. N., London, N6A 5B7, Ontario, Canada.,Division of Orthopaedic Surgery, Department of Surgery, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada.,Surgical Innovation Program, Lawson Health Research Institute, 339 Windermere Road, London, N6A 5A5, ON, Canada
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Goyal P, Howard JL, Yuan X, Teeter MG, Lanting BA. Effect of Acetabular Position on Polyethylene Liner Wear Measured Using Simultaneous Biplanar Acquisition. J Arthroplasty 2017; 32:1670-1674. [PMID: 28087161 DOI: 10.1016/j.arth.2016.11.057] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2016] [Revised: 11/10/2016] [Accepted: 11/29/2016] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND Studies that have previously examined the relationship between acetabular component inclination angle and polyethylene wear have shown increased wear of conventional polyethylene with high inclination angles. To date, there are no long-term in vivo studies examining the correlation between cup position and polyethylene wear with highly crosslinked polyethylene. METHODS An institutional arthroplasty database was used to identify patients who had metal-on-highly crosslinked polyethylene primary total hip arthroplasty using the same component design with a minimum follow-up of 10 years. A modified radiostereometric analysis examination setup was utilized, recreating standard anteroposterior and cross-table lateral examinations in a single stereo radiostereometric analysis acquisition. The same radiographs were used to measure inclination angle and anteversion. RESULTS A total of 43 hips were included for analysis in this study. Average follow-up was 12.3 ± 1.2 years. The average linear wear rate was calculated to be 0.066 ± 0.066 mm/y. Inclination angle was not correlated with polyethylene wear rate (P = .82). Anteversion was also not correlated with polyethylene wear rate (P = .11). CONCLUSION At long-term follow-up of >10 years, highly crosslinked polyethylene has a very low wear rate. This excellent tribology is independent of acetabular position. The low wear rate highlights the excellent results of metal on highly crosslinked polyethylene, and supports its use in total hip arthroplasty.
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Affiliation(s)
- Prateek Goyal
- Division of Orthopaedic Surgery, Department of Surgery, Schulich School of Medicine & Dentistry, Western University, London, ON, Canada
| | - James L Howard
- Division of Orthopaedic Surgery, Department of Surgery, Schulich School of Medicine & Dentistry, Western University, London, ON, Canada
| | - Xunhua Yuan
- Imaging Research Laboratories, Robarts Research Institute, Schulich School of Medicine & Dentistry, Western University, London, ON, Canada
| | - Matthew G Teeter
- Division of Orthopaedic Surgery, Department of Surgery, Schulich School of Medicine & Dentistry, Western University, London, ON, Canada; Department of Medical Biophysics, Schulich School of Medicine & Dentistry, Western University, London, ON, Canada; Surgical Innovation Program, Lawson Health Research Institute, London, ON, Canada
| | - Brent A Lanting
- Division of Orthopaedic Surgery, Department of Surgery, Schulich School of Medicine & Dentistry, Western University, London, ON, Canada
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Callary SA, Solomon LB, Holubowycz OT, Campbell DG, Howie DW. Accuracy of methods to measure femoral head penetration within metal-backed acetabular components. J Orthop Res 2017; 35:988-996. [PMID: 27357247 DOI: 10.1002/jor.23356] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 06/22/2016] [Indexed: 02/04/2023]
Abstract
A number of different software programs are used to investigate the in vivo wear of polyethylene bearings in total hip arthroplasty. With wear rates below 0.1 mm/year now commonly being reported for highly cross-linked polyethylene (XLPE) components, it is important to identify the accuracy of the methods used to measure such small movements. The aims of this study were to compare the accuracy of current software programs used to measure two-dimensional (2D) femoral head penetration (FHP) and to determine whether the accuracy is influenced by larger femoral heads or by different methods of representing the acetabular component within radiostereometric analysis (RSA). A hip phantom was used to compare known movements of the femoral head within a metal-backed acetabular component to FHP measured radiographically using RSA, Hip Analysis Suite (HAS), PolyWare, Ein Bild Roentgen Analyse (EBRA), and Roentgen Monographic Analysis Tool (ROMAN). RSA was significantly more accurate than the HAS, PolyWare, and ROMAN methods when measuring 2D FHP with a 28 mm femoral head. Femoral head size influenced the accuracy of HAS and ROMAN 2D FHP measurements, EBRA proximal measurements, and RSA measurements in the proximal and anterior direction. The use of different acetabular reference segments did not influence accuracy of RSA measurements. The superior accuracy and reduced variability of RSA wear measurements allow much smaller cohorts to be used in RSA clinical wear studies than those utilizing other software programs. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:988-996, 2017.
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Affiliation(s)
- Stuart A Callary
- Discipline of Orthopaedics and Trauma, The University of Adelaide, Adelaide, South Australia, Australia.,Department of Orthopaedics and Trauma, Royal Adelaide Hospital, Level 4 Bice Building, North Terrace, Adelaide, South Australia, 5000, Australia
| | - Lucian B Solomon
- Discipline of Orthopaedics and Trauma, The University of Adelaide, Adelaide, South Australia, Australia.,Department of Orthopaedics and Trauma, Royal Adelaide Hospital, Level 4 Bice Building, North Terrace, Adelaide, South Australia, 5000, Australia
| | - Oksana T Holubowycz
- Discipline of Orthopaedics and Trauma, The University of Adelaide, Adelaide, South Australia, Australia
| | - David G Campbell
- Wakefield Orthopaedic Clinic, Adelaide, South Australia, Australia
| | - Donald W Howie
- Discipline of Orthopaedics and Trauma, The University of Adelaide, Adelaide, South Australia, Australia.,Department of Orthopaedics and Trauma, Royal Adelaide Hospital, Level 4 Bice Building, North Terrace, Adelaide, South Australia, 5000, Australia
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Mahato NK, Montuelle S, Goubeaux C, Cotton J, Williams S, Thomas J, Clark BC. Quantification of intervertebral displacement with a novel MRI-based modeling technique: Assessing measurement bias and reliability with a porcine spine model. Magn Reson Imaging 2016; 38:77-86. [PMID: 28027908 DOI: 10.1016/j.mri.2016.12.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 12/21/2016] [Accepted: 12/22/2016] [Indexed: 11/26/2022]
Abstract
The purpose of this study was to develop a novel magnetic resonance imaging (MRI)-based modeling technique for measuring intervertebral displacements. Here, we present the measurement bias and reliability of the developmental work using a porcine spine model. Porcine lumbar vertebral segments were fitted in a custom-built apparatus placed within an externally calibrated imaging volume of an open-MRI scanner. The apparatus allowed movement of the vertebrae through pre-assigned magnitudes of sagittal and coronal translation and rotation. The induced displacements were imaged with static (T1) and fast dynamic (2D HYCE S) pulse sequences. These images were imported into animation software, in which these images formed a background 'scene'. Three-dimensional models of vertebrae were created using static axial scans from the specimen and then transferred into the animation environment. In the animation environment, the user manually moved the models (rotoscoping) to perform model-to-'scene' matching to fit the models to their image silhouettes and assigned anatomical joint axes to the motion-segments. The animation protocol quantified the experimental translation and rotation displacements between the vertebral models. Accuracy of the technique was calculated as 'bias' using a linear mixed effects model, average percentage error and root mean square errors. Between-session reliability was examined by computing intra-class correlation coefficients (ICC) and the coefficient of variations (CV). For translation trials, a constant bias (β0) of 0.35 (±0.11) mm was detected for the 2D HYCE S sequence (p=0.01). The model did not demonstrate significant additional bias with each mm increase in experimental translation (β1Displacement=0.01mm; p=0.69). Using the T1 sequence for the same assessments did not significantly change the bias (p>0.05). ICC values for the T1 and 2D HYCE S pulse sequences were 0.98 and 0.97, respectively. For rotation trials, a constant bias (β0) of 0.62 (±0.12)° was detected for the 2D HYCE S sequence (p<0.01). The model also demonstrated an additional bias (β1Displacement) of 0.05° with each degree increase in the experimental rotation (p<0.01). Using T1 sequence for the same assessments did not significantly change the bias (p>0.05). ICC values for the T1 and 2D HYCE S pulse sequences were recorded 0.97 and 0.91, respectively. This novel quasi-static approach to quantifying intervertebral relationship demonstrates a reasonable degree of accuracy and reliability using the model-to-image matching technique with both static and dynamic sequences in a porcine model. Future work is required to explore multi-planar assessment of real-time spine motion and to examine the reliability of our approach in humans.
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Affiliation(s)
- Niladri K Mahato
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH 45701, United States; Department of Biomedical Sciences, Ohio University, Athens, OH 45701, United States.
| | - Stephane Montuelle
- Department of Biomedical Sciences, Ohio University, Athens, OH 45701, United States.
| | - Craig Goubeaux
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH 45701, United States; Department of Mechanical Engineering, Ohio University, Athens, OH 45701, United States.
| | - John Cotton
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH 45701, United States; Department of Mechanical Engineering, Ohio University, Athens, OH 45701, United States.
| | - Susan Williams
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH 45701, United States; Department of Biomedical Sciences, Ohio University, Athens, OH 45701, United States.
| | - James Thomas
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH 45701, United States; Department of Biomedical Sciences, Ohio University, Athens, OH 45701, United States; School of Rehabilitation and Communication Sciences, Ohio University, Athens, OH 45701, United States.
| | - Brian C Clark
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH 45701, United States; Department of Biomedical Sciences, Ohio University, Athens, OH 45701, United States; Department of Geriatric Medicine, Ohio University, Athens, OH 45701, United States.
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Broberg JS, Yuan X, Teeter MG. Investigation of imaging magnification in radiostereometric analysis. Proc Inst Mech Eng H 2016; 231:92-95. [PMID: 27913629 DOI: 10.1177/0954411916676850] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Radiostereometric analysis is a highly accurate imaging technique. A recent advance in radiostereometric analysis is the use of flat panel digital radiography, which provides the opportunity for quick analysis using radiostereometric analysis. However, such a setup is expensive. Using large cassettes for small joints could minimize the cost. In this article, we investigated the influence of cassette size for small joint examinations with a biplanar radiostereometric analysis setup. Our results indicated that there is no significant difference in the precision when using large cassettes over small cassettes, whether or not imaging magnification is applied.
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Affiliation(s)
- Jordan S Broberg
- 1 Department of Medical Biophysics, Schulich School of Medicine & Dentistry, Western University, London, ON, Canada
| | - Xunhua Yuan
- 2 Imaging Research Laboratories, Robarts Research Institute, Schulich School of Medicine & Dentistry, Western University, London, ON, Canada
| | - Matthew G Teeter
- 1 Department of Medical Biophysics, Schulich School of Medicine & Dentistry, Western University, London, ON, Canada.,2 Imaging Research Laboratories, Robarts Research Institute, Schulich School of Medicine & Dentistry, Western University, London, ON, Canada.,3 Division of Orthopaedic Surgery, Department of Surgery, Schulich School of Medicine & Dentistry, Western University, London, ON, Canada.,4 Surgical Innovation Program, Lawson Health Research Institute, London, ON, Canada
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13
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Yuan X, Lam Tin Cheung K, Howard JL, Lanting BA, Teeter MG. Radiostereometric analysis using clinical radiographic views: Validation measuring total hip replacement wear. J Orthop Res 2016; 34:1521-8. [PMID: 26792569 DOI: 10.1002/jor.23170] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 01/13/2016] [Indexed: 02/04/2023]
Abstract
Radiostereometric analysis (RSA) is a stereo X-ray technique used in clinical research studies to evaluate micro-motion and wear of orthopaedic implants within bone. While highly accurate and precise, its adoption has been limited due to technical requirements such as the need for implanted marker beads and radiograph view angles determined by a calibration cage. We propose a new technique that separates the calibration procedure from the patient examination, enabling clinical radiograph views to be used for RSA measurements. The concept of a reference plate was adapted to establish the link between calibration procedure and patient examination procedure for cassette radiography, which may not be necessary for digital radiography. A hip wear phantom was used to validate this technique by comparing the error and repeatability of the novel procedure with that of conventional RSA. Femoral head penetration was measured versus the acetabular cup (head/cup) and marker beads in the acetabular liner (head/liner). Conventional RSA had lower inferior-superior average error (p = 0.03 for head/cup) while the modified RSA had lower anterior-posterior average error (p = 0.01). Average error was greater but not significantly so for the medial-lateral (p = 0.06) and 3D (p = 0.97) measurements. The head/liner method had lower average errors (p < 0.0001) for both procedures, but did not affect repeatability, which was similar between techniques. The novel procedure's average error and repeatability was therefore, similar to conventional RSA. This new technique could be applied to any joint with two clinical radiograph view angles pending further validation in subjects. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1521-1528, 2016.
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Affiliation(s)
- Xunhua Yuan
- Imaging Research Laboratories, Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Kimberley Lam Tin Cheung
- Department of Medical Biophysics, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - James L Howard
- Division of Orthopaedic Surgery, Department of Surgery, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Brent A Lanting
- Division of Orthopaedic Surgery, Department of Surgery, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Matthew G Teeter
- Department of Medical Biophysics, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
- Division of Orthopaedic Surgery, Department of Surgery, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
- Surgical Innovation Program, Lawson Health Research Institute, London, Ontario, Canada
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Teeter MG, Thoren J, Yuan X, McCalden RW, MacDonald SJ, Lanting BA, Naudie DDR. Migration of a cemented fixed-bearing, polished titanium tibial baseplate (Genesis II) at ten years : a radiostereometric analysis. Bone Joint J 2016; 98-B:616-21. [PMID: 27143731 DOI: 10.1302/0301-620x.98b5.36865] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 01/14/2016] [Indexed: 11/05/2022]
Abstract
AIMS The purpose of the present study was to examine the long-term fixation of a cemented fixed-bearing polished titanium tibial baseplate (Genesis ll). PATIENTS AND METHODS Patients enrolled in a previous two-year prospective trial (n = 35) were recalled at ten years. Available patients (n = 15) underwent radiostereometric analysis (RSA) imaging in a supine position using a conventional RSA protocol. Migration of the tibial component in all planes was compared between initial and ten-year follow-up. Outcome scores including the Knee Society Score, Western Ontario and McMaster Universities Arthritis Index, 12-item Short Form Health Survey, Forgotten Joint Score, and University of California, Los Angeles Activity Score were recorded. RESULTS At ten years, the mean migration of the tibial component was less than 0.1 mm and 0.1° in all planes relative to the post-operative RSA exam. Maximum total point movement increased with time (p = 0.002) from 0.23 mm (sd 0.18) at six weeks to 0.42 mm (sd 0.20) at ten years. CONCLUSION The low level of tibial baseplate migration found in the present study correlates to the low rate of revision for this implant as reported in individual studies and in joint replacement registries. TAKE HOME MESSAGE Overall, the implant was found to be well fixed at ten years, supporting its continued clinical use and the predictive power of RSA for determining long-term fixation of implants. Cite this article: Bone Joint J 2016;98-B:616-21.
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Affiliation(s)
- M G Teeter
- Lawson Health Research Institute, 339 Windermere Road, London, ON, N6A 5A5, Canada
| | - J Thoren
- London Health Sciences Centre, 339 Windermere Road, London, ON, N6A 5A5, Canada
| | - X Yuan
- Robarts Research Institute, 1151 Richmond Street, London, ON, N6A 3K7, Canada
| | - R W McCalden
- London Health Sciences Centre, 339 Windermere Road, London, ON, N6A 5A5, Canada
| | - S J MacDonald
- London Health Sciences Centre, 339 Windermere Road, London, ON, N6A 5A5, Canada
| | - B A Lanting
- London Health Sciences Centre, 339 Windermere Road, London, ON, N6A 5A5, Canada
| | - D D R Naudie
- London Health Sciences Centre, 339 Windermere Road, London, ON, N6A 5A5, Canada
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Bojan AJ, Bragdon C, Jönsson A, Ekholm C, Kärrholm J. Three-dimensional bone-implant movements in trochanteric hip fractures: Precision and accuracy of radiostereometric analysis in a phantom model. J Orthop Res 2015; 33:705-11. [PMID: 25640537 DOI: 10.1002/jor.22822] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 01/06/2015] [Indexed: 02/04/2023]
Abstract
The accuracy and precision of RSA were evaluated in the experimental study of screw cut-out complication after fixation of trochanteric fractures. A plastic bone model of a two-part trochanteric fracture was constructed with a Gamma nail implant incorporating RSA markers. The femoral head fragment was attached to a separate rotational table and the femoral shaft was mounted on the micrometer. Three main motions were simulated: Femoral head translation and rotation along the axis of the lag screw and fracture fragment translation along anatomical axes. Accuracy and precision were determined according to ISO 16,087 and ASTM standard F2385-04. Translations along the lag screw axis were measured with a precision within ±0.14 mm and an accuracy within ±0.03 mm. With simultaneous translations along all three anatomical axes, lowest precision was measured for the x-axis (±0.29, 0.07 mm, respectively), but improved when analyzed as a vector (±0.08, 0.03 mm). The precision and accuracy of femoral head rotations were within 0.5° and 0.18°, respectively. The resolution of the RSA method tested in this model was high, though it varied depending on the type of analyzed motion. This information is valuable when selecting and interpreting outcome parameters evaluating implant migration and osteosynthesis stability in future clinical RSA studies.
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Affiliation(s)
- Alicja J Bojan
- Department of Orthopaedics, Institute of Clinical Sciences at Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden
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Tersi L, Stagni R. Effect of calibration error on bone tracking accuracy with fluoroscopy. J Biomech Eng 2014; 136:054502. [PMID: 24598887 DOI: 10.1115/1.4027058] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 03/06/2014] [Indexed: 12/15/2022]
Abstract
Model-based 3D-fluoroscopy can quantify joint kinematics with 1 mm and 1 deg accuracy level. A calibration based on the acquisition of devices of known geometry is usually applied to size the system. This study aimed at quantifying the sensitivity of the fluoroscopic pose estimation accuracy specifically to errors in the calibration process, excluding other sources of error. X-ray focus calibration error was quantified for different calibration setups, and its propagation to the pose estimation was characterized in-silico. Focus reference position influenced the calibration error dispersion, while calibration cage pose affected its bias. In the worst-case scenario, the estimation error of the principal point and of the focus distance was lower than 1 mm and 2 mm, respectively. The consequent estimation of joint angles was scarcely influenced by calibration errors. A linear trend was highlighted for joint translations, with a sensitivity proportional to the distance between the model and the image plane, resulting in a submillimeter error for realistic calibration errors. The biased component of the error is compensated when computing relative joint kinematics between two segments.
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Teeter MG, Seslija P, Milner JS, Nikolov HN, Yuan X, Naudie DDR, Holdsworth DW. Quantification ofin vivoimplant wear in total knee replacement from dynamic single plane radiography. Phys Med Biol 2013; 58:2751-67. [DOI: 10.1088/0031-9155/58/9/2751] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Seslija P, Teeter MG, Yuan X, Naudie DDR, Bourne RB, MacDonald SJ, Peters TM, Holdsworth DW. Measurement of joint kinematics using a conventional clinical single-perspective flat-panel radiography system. Med Phys 2012; 39:6090-103. [DOI: 10.1118/1.4752205] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Allen MJ, Leone KA, Dunbar MJ, Race A, Rosenbaum PF, Sacks JM. Tibial component fixation with a peri-apatite coating: evaluation by radiostereometric analysis in a canine total knee arthroplasty model. J Arthroplasty 2012; 27:1138-48. [PMID: 22364907 DOI: 10.1016/j.arth.2011.12.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Accepted: 12/24/2011] [Indexed: 02/01/2023] Open
Abstract
Cementless fixation for the tibial component in total knee arthroplasty (TKA) remains problematic. Peri-Apatite (PA), a solution-deposited hydroxyapatite, is under investigation as an option for improving the fixation of cementless tibial components. In this study, radiostereometric analysis was used to document implant migration in 48 dogs that underwent TKA with cementless, PA-coated, or cemented tibial components. Migration at 12 weeks was similar in the 2 groups. At 12 months, there was greater migration in the PA-coated group, but the difference between the 2 groups was below the threshold considered clinically significant. In this canine TKA model, cementless fixation with PA performed less well than did cemented fixation, but not to a degree that would make a clinical difference in the short term.
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Affiliation(s)
- Matthew J Allen
- Department of Veterinary Clinical Sciences, The Ohio State University, Columbus, Ohio 43210, USA
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20
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Kedgley AE, Fox AMV, Jenkyn TR. Image intensifier distortion correction for fluoroscopic RSA: the need for independent accuracy assessment. J Appl Clin Med Phys 2012; 13:3441. [PMID: 22231207 PMCID: PMC5716127 DOI: 10.1120/jacmp.v13i1.3441] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2010] [Revised: 09/16/2011] [Accepted: 09/07/2011] [Indexed: 11/23/2022] Open
Abstract
Fluoroscopic images suffer from multiple modes of image distortion. Therefore, the purpose of this study was to compare the effects of correction using a range of two-dimensional polynomials and a global approach. The primary measure of interest was the average error in the distances between four beads of an accuracy phantom, as measured using RSA. Secondary measures of interest were the root mean squared errors of the fit of the chosen polynomial to the grid of beads used for correction, and the errors in the corrected distances between the points of the grid in a second position. Based upon the two-dimensional measures, a polynomial of order three in the axis of correction and two in the perpendicular axis was preferred. However, based upon the RSA reconstruction, a polynomial of order three in the axis of correction and one in the perpendicular axis was preferred. The use of a calibration frame for these three-dimensional applications most likely tempers the effects of distortion. This study suggests that distortion correction should be validated for each of its applications with an independent "gold standard" phantom.
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Affiliation(s)
- Angela E Kedgley
- Department of Bioengineering, Imperial College London, South Kensington Campus, London, SW7 2AZ United Kingdom.
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21
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Solomon LB, Stevenson AW, Callary SA, Sullivan TR, Howie DW, Chehade MJ. The accuracy and precision of radiostereometric analysis in monitoring tibial plateau fractures. Acta Orthop 2010; 81:487-94. [PMID: 20465528 PMCID: PMC2917573 DOI: 10.3109/17453674.2010.487930] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND AND PURPOSE The application of radiostereometric analysis (RSA) to monitor stability of tibial plateau fractures during healing is both limited and yet to be validated. We therefore evaluated the accuracy and precision of RSA in a tibial plateau fracture model. METHODS Combinations of 3, 6, and 9 markers in a lateral condyle fracture were evaluated with reference to 6 proximal tibial arrangements. Translation and rotation accuracy was assessed with displacement-controlled stages, while precision was assessed with dynamic double examinations. A comparison of error according to marker number and arrangement was completed with 2-way ANOVA models. RESULTS The results were improved using more tantalum markers in each segment. In the fracture fragment, marker scatter in all axes was achieved by a circumferential arrangement (medial, anterior, and lateral) of the tantalum markers above the fixation devices. Markers placed on either side of the tibial tuberosity and in the medial aspect of the fracture split represented the proximal tibial reference segment best. Using 6 markers with this distribution in each segment, the translation accuracy (root mean square error) was less than 37 mum in all axes. The precision (95% confidence interval) was less than +/- 16 mum in all axes in vitro. Rotation, tested around the x-axis, had an accuracy of less than 0.123 degrees and a precision of +/- 0.024 degrees. INTERPRETATION RSA is highly accurate and precise in the assessment of lateral tibial plateau fracture fragment movement. The validation of our center's RSA system provides evidence to support future clinical RSA fracture studies.
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Affiliation(s)
- Lucian B Solomon
- Discipline of Orthopaedics and Trauma, University of Adelaide, and Department of Orthopaedics and Trauma, Royal Adelaide Hospital,Correspondence:
| | - Aaron W Stevenson
- Discipline of Orthopaedics and Trauma, University of Adelaide, and Department of Orthopaedics and Trauma, Royal Adelaide Hospital
| | - Stuart A Callary
- Discipline of Orthopaedics and Trauma, University of Adelaide, and Department of Orthopaedics and Trauma, Royal Adelaide Hospital
| | - Thomas R Sullivan
- Discipline of Public Health, University of Adelaide, AdelaideAustralia
| | - Donald W Howie
- Discipline of Orthopaedics and Trauma, University of Adelaide, and Department of Orthopaedics and Trauma, Royal Adelaide Hospital
| | - Mellick J Chehade
- Discipline of Orthopaedics and Trauma, University of Adelaide, and Department of Orthopaedics and Trauma, Royal Adelaide Hospital
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22
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Kedgley AE, Jenkyn TR. RSA calibration accuracy of a fluoroscopy-based system using nonorthogonal images for measuring functional kinematics. Med Phys 2009; 36:3176-80. [DOI: 10.1118/1.3147142] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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