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Van der Lelij TJN, Koster LA, Marang-van de Mheen PJ, Toksvig-Larsen S, Nelissen RGHH, Kaptein BL. Influence of marker-selection method in radiostereometric analysis of total knee arthroplasty on tibial baseplate migration patterns: a secondary analysis of a randomized controlled trial with 5-year follow-up. Acta Orthop 2024; 95:157-165. [PMID: 38597226 PMCID: PMC10959012 DOI: 10.2340/17453674.2024.40184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 02/19/2024] [Indexed: 04/11/2024] Open
Abstract
BACKGROUND AND PURPOSE Different marker-selection methods are applied to represent implant and tibial segments in radiostereometric analysis (RSA) studies of total knee arthroplasty (TKA). Either a consistent set of markers throughout subsequent RSA examinations ("consistent-marker method") is used or all available markers at each follow-up ("all-marker method"). The aim of this secondary analysis was to compare marker-selection methods on individual and group level TKA migration results. METHODS Data from a randomized RSA study with 72 patients was included. Tibial baseplate migration was evaluated at 3 months, 1, 2, and 5 years postoperatively with both marker-selection methods. Additionally, migration was calculated using 5 fictive points, either plotted based on the consistent set of markers or all available markers. RESULTS Migration could be calculated with both marker-selection methods for 248 examinations. The same prosthesis and bone markers (n = 136), different prosthesis markers (n = 71), different bone markers (n = 21), or different prosthesis and bone markers (n = 20) were used. The mean difference in maximum total point motion (MTPM) between all examinations was 0.02 mm, 95% confidence interval -0.26 to 0.31 mm. 5 implants were classified as continuously migrating with the consistent-marker method versus 6 implants (same 5 plus one additional implant) with the all-marker method. Using fictive points, fewer implants were classified as continuously migrating in both marker-selection methods. Differences between TKA groups in mean MTPM were comparable with both marker-selection methods, also when fictive points were used. CONCLUSION Estimated group differences in mean MTPM were similar between marker-selection methods, but individual migration results differed. The latter has implications when classifying implants for estimated risk of future loosening.
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Affiliation(s)
| | - Lennard A Koster
- Department of Orthopaedics, Leiden University Medical Center, Leiden, The Netherlands
| | - Perla J Marang-van de Mheen
- Department of Orthopaedics, Leiden University Medical Center, Leiden, The Netherlands; Safety & Security Science and Centre for Safety in Healthcare, Delft University of Technology, Delft, The Netherlands
| | - Sören Toksvig-Larsen
- Department of Orthopaedics, Hässleholm Hospital, Hässleholm, Sweden; Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Rob G H H Nelissen
- Department of Orthopaedics, Leiden University Medical Center, Leiden, The Netherlands
| | - Bart L Kaptein
- Department of Orthopaedics, Leiden University Medical Center, Leiden, The Netherlands
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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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Yilmaz M, Holm CE, Lind T, Flivik G, Odgaard A, Petersen MM. Bone remodeling and implant migration of uncemented femoral and cemented asymmetrical tibial components in total knee arthroplasty - DXA and RSA evaluation with 2-year follow up. Knee Surg Relat Res 2021; 33:25. [PMID: 34404487 PMCID: PMC8369662 DOI: 10.1186/s43019-021-00111-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 07/22/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Aseptic loosening is one of the major reasons for late revision in total knee arthroplasty (TKA). The risk of aseptic loosening can be detected using radiostereometric analysis (RSA), whereby micromovements (migration) can be measured, and thus RSA is recommended in the phased introduction of orthopedic implants. Decrease in bone mineral density (BMD), as measured by dual-energy x ray absorptiometry (DXA), is related to the breaking strength of the bone, which is measured concurrently by RSA. The aim of the study was to evaluate bone remodeling and implant migration with cemented asymmetrical tibial and uncemented femoral components after TKA with a follow up period of 2 years. METHODS This was a prospective longitudinal cohort study of 29 patients (number of female/male patients 17/12, mean age 65.2 years), received a hybrid Persona® TKA (Zimmer Biomet, Warsaw, IN, USA) consisting of a cemented tibial, an all-polyethylene patella, and uncemented trabecular metal femoral components. Follow up: preoperative, 1 week, and 3, 6, 12 and 24 months after surgery, and double examinations for RSA and DXA were performed at 12 months. RSA results were presented as maximal total point of motion (MTPM) and segmental motion (translation and rotation), and DXA results were presented as changes in BMD in different regions of interest (ROI). RESULTS MTPM at 3, 6, 12, and 24 months was 0.65 mm, 0.84 mm, 0.92 mm, and 0.96 mm for the femoral component and 0.54 mm, 0.60 mm, 0.64 mm, and 0.68 mm, respectively, for the tibial component. The highest MTPM occurred within the first 3 months. Afterwards most of the curves flattened and stabilized. Between 12 and 24 months after surgery, 16% of femoral components had migrated by more than 0.10 mm and 15% of tibial components had migrated by more than 0.2 mm. Percentage change in BMD in each ROI for distal femur was as follows: ROI I 26.7%, ROI II 9.2% and ROI III 3.3%. BMD and at the proximal tibia: ROI I 8.2%, ROI II 8.6% and ROI III 7.0% after 2 years compared with 1 week postoperative results. There was no significant correlation between maximal percentwise change in BMD and MTPM after 2 years. CONCLUSION Migration patterns and changes in BMD related to femoral components after TKA in our study correspond well with previous studies; we observed marginally greater migration with the tibial component.
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Affiliation(s)
- Müjgan Yilmaz
- Department of Orthopedic Surgery, University Hospital of Copenhagen, Rigshospitalet, Inge Lehmanns Vej 6, 2100, Copenhagen Ø, Denmark. .,Department of Orthopedic Surgery, University Hospital of Copenhagen, Herlev-Gentofte Hospital, Gentofte Hospitalsvej 1, 2900, Hellerup, Denmark. .,Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Christina Enciso Holm
- Department of Orthopedic Surgery, University Hospital of Copenhagen, Rigshospitalet, Inge Lehmanns Vej 6, 2100, Copenhagen Ø, Denmark
| | - Thomas Lind
- Department of Orthopedic Surgery, University Hospital of Copenhagen, Herlev-Gentofte Hospital, Gentofte Hospitalsvej 1, 2900, Hellerup, Denmark
| | - Gunnar Flivik
- Department of Orthopedics, Skane University Hospital, Clinical Sciences, Lund University, Entrégaten 7, 222 42, Lund, Sweden
| | - Anders Odgaard
- Department of Orthopedic Surgery, University Hospital of Copenhagen, Rigshospitalet, Inge Lehmanns Vej 6, 2100, Copenhagen Ø, Denmark.,Department of Orthopedic Surgery, University Hospital of Copenhagen, Herlev-Gentofte Hospital, Gentofte Hospitalsvej 1, 2900, Hellerup, Denmark.,Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Michael Mørk Petersen
- Department of Orthopedic Surgery, University Hospital of Copenhagen, Rigshospitalet, Inge Lehmanns Vej 6, 2100, Copenhagen Ø, Denmark.,Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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[Early assessment of the risk of later implantloosening using Roentgen Sterophotogrammetric Analysis (RSA)]. DER ORTHOPADE 2020; 49:1042-1048. [PMID: 33108489 DOI: 10.1007/s00132-020-04027-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
BACKGROUND Aseptic implant loosening is the most common cause of implant revisions in total hip and total knee arthroplasty. Roentgen Stereophotogrammetric Analysis (RSA) represents the current gold standard for the in-vivo assessment of implant fixation. PRESENT SITUATION Long-term clinical trials have shown that continuous implant migration within the first two postoperative years correlates strongly with a later aseptic loosening. Thus, the implant migration measured with RSA can be regarded as a reliable surrogate marker for later implant loosening. Over the past 40 years, RSA has been continuously further developed, and the model-based RSA approach has reduced the effort involved since markers attached to implant are no longer needed. PERSPECTIVES The RSA method is gaining importance in the certification process of new orthopaedic implants-for example, the Dutch Orthopedic Society has recommended phased-introduction and RSA studies for new hip implants. Furthermore, in the context of the new EU Medical Device Regulation (MDR), which took effect in May 2017, RSA gained relevance for investigating clinically unproven implants. Critics who associate MDR with hindering innovation can be countered in that the RSA method provides a predictive assessment of implant fixation after only two years of follow-up, which is significantly shorter than standard long-term clinical trials.
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Xu J, Sonntag R, Kretzer JP, Taylor D, Forst R, Seehaus F. Model-Based Roentgen Stereophotogrammetric Analysis to Monitor the Head-Taper Junction in Total Hip Arthroplasty in Vivo-And They Do Move. MATERIALS 2020; 13:ma13071543. [PMID: 32230788 PMCID: PMC7178274 DOI: 10.3390/ma13071543] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 03/23/2020] [Accepted: 03/24/2020] [Indexed: 12/01/2022]
Abstract
Model-based Roentgen stereophotogrammetric analysis (RSA) using elementary geometrical shape (EGS) models allows migration measurement of implants without the necessity of additional attached implant markers. The aims of this study were: (i) to assess the possibility of measuring potential head–taper movement in THA in vivo using model-based RSA and (ii) to prove the validity of measured head–taper migration data in vitro and in vivo. From a previous RSA study with a 10 years follow-up, retrospectively for n = 45 patients head–taper migration was calculated as the relative migration between femoral ball head and taper of the femoral stem using model-based RSA. A head–taper migration of 0.026 mm/year can be detected with available RSA technology. In vitro validation showed a total migration of 268 ± 11 µm along the taper axis in a similar range to what has been reported using the RSA method. In vivo, a proof for interchangeable applicability of model-based RSA (EGS) and standard marker-based RSA methods was indicated by a significant deviation within the migration result after 12-month follow-up for all translation measurements, which was significantly correlated to the measured head–taper migration (r from 0.40 to 0.67; p < 0.05). The results identified that model-based RSA (EGS) could be used to detect head–taper migration in vivo and the measured movement could be validated in vitro and in vivo as well. Those findings supported the possibility of applying RSA for helping evaluate the head–taper corrosion related failure (trunnionosis).
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Affiliation(s)
- Jing Xu
- Department of Orthopaedic Surgery, Faculty of Medicine, University of Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Robert Sonntag
- Laboratory of Biomechanics and Implant Research, Clinic for Orthopedics and Trauma Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, 69118 Heidelberg, Germany
| | - J. Philippe Kretzer
- Laboratory of Biomechanics and Implant Research, Clinic for Orthopedics and Trauma Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, 69118 Heidelberg, Germany
| | - Dominic Taylor
- Department of Orthopaedic Surgery, Faculty of Medicine, University of Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Raimund Forst
- Department of Orthopaedic Surgery, Faculty of Medicine, University of Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Frank Seehaus
- Department of Orthopaedic Surgery, Faculty of Medicine, University of Erlangen-Nürnberg, 91054 Erlangen, Germany
- Correspondence:
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Lindgren L, Jørgensen PB, Mørup RMS, Jensen M, Rømer L, Kaptein B, Stilling M. Similar patient positioning: A key factor in follow-up studies when using model-based radiostereometric analysis of the hip. Radiography (Lond) 2020; 26:e45-e51. [PMID: 32052775 DOI: 10.1016/j.radi.2019.10.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 08/30/2019] [Accepted: 10/22/2019] [Indexed: 01/28/2023]
Abstract
INTRODUCTION Despite protocols, patients are not positioned exactly alike at radiostereometric (RSA) follow-up examinations, and it is unknown how much variation is tolerable. We report precision for optimal and extreme position differences from a phantom hip-study, and clinical precision of hip-RSA. METHODS A femoral stem with 3 bead-towers was fixed in a saw bone with bone-markers (phantom), and series of RSA examinations within optimal (5 × 5 cm and 5°) and extreme (20 × 30 cm and 30°) phantom positions were obtained. Double-examination RSA of 12 patients with the same femoral stem type were analyzed. Both model-based (CAD) and marker-based (MM) analysis was used. Precision was reported as standard deviation of differences. RESULTS Precision for translations in the optimal and extreme phantom position were below 0.06 mm and 0.02 mm for MM analysis, and below 0.05 mm and 0.18 mm for CAD analysis, respectively. Precision for rotations in the optimal and extreme phantom rotation were below 0.18° and 0.26° for MM analysis, and below 0.34° and 0.52° for CAD analysis, respectively. Clinical precision was 0.29 mm and 0.44° for MM analysis, and 0.40 mm and 1.59° for CAD analysis. CONCLUSION Extreme differences in patient position during RSA examination negatively affects precision, and CAD model-analysis was more sensitive than MM analysis. Longitudinal translation and rotation about the long stem-axis are the effect parameters which are most affected by position and rotation changes, and also the best indicators of implant loosening. IMPLICATIONS FOR PRACTICE Based on our research, we recommend that similar patient positioning between follow-up RSA examinations is debated and prioritized.
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Affiliation(s)
- L Lindgren
- Department of Radiology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200, Aarhus, Denmark.
| | - P B Jørgensen
- Orthopedic Research Unit, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200, Aarhus, Denmark.
| | - R M S Mørup
- Orthopedic Research Unit, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200, Aarhus, Denmark.
| | - M Jensen
- Department of Radiology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200, Aarhus, Denmark.
| | - L Rømer
- Department of Radiology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200, Aarhus, Denmark.
| | - B Kaptein
- Biomechanics and Imaging Group (BIG), Leiden University Medical Center, P.O. Box 9600, 2300 RC, Leiden, the Netherlands.
| | - M Stilling
- Orthopedic Research Unit, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200, Aarhus, Denmark; Department of Clinical Medicine, Aarhus University, Palle Juul-Jensens Boulevard 99, 8200, Aarhus, Denmark.
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van Hamersveld KT, Marang–van de Mheen PJ, Koster LA, Nelissen RGHH, Toksvig-Larsen S, Kaptein BL. Marker-based versus model-based radiostereometric analysis of total knee arthroplasty migration: a reanalysis with comparable mean outcomes despite distinct types of measurement error. Acta Orthop 2019; 90:366-372. [PMID: 31017513 PMCID: PMC7025693 DOI: 10.1080/17453674.2019.1605692] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Background and purpose - Pooling data of studies evaluating total knee arthroplasty migration using radiostereometric analysis (RSA) may be compromised when the RSA method used would influence estimated differences between groups. We therefore reanalyzed a marker-based RSA study with model-based RSA to assess possible limitations of each RSA method, including insert micromotions in modular TKA and their effect on estimated group differences. Patients and methods - All patients had received a cemented Triathlon implant (Stryker, Mahwah, NJ, USA) with either an all-polyethylene (n = 29) or a metal-backed (n = 28) tibial component. The latter group was reanalyzed with model-based RSA. Precision of each RSA method was calculated using double examinations. Bland-Altman plots were constructed to determine the limits of agreement between the 2 RSA methods. Polyethylene insert micromotion was quantified by measuring migration with respect to the metal tray. Finally, analyses of the original study were repeated with the model-based RSA results. Results - Systematic differences were found in translations between marker-based and model-based RSA as a result of different reference origins being used for migration calculations. Micromotions of the polyethylene insert within the metal tray were negligibly small. Mean migration results were comparable between marker-based and model-based RSA when using the same reference origin, even though conclusions on individual patients may differ between RSA methods due to various types of measurement error (e.g., marker occlusion and model-fit inaccuracies). Interpretation - At least for the studied TKA design, pooling mean migration data of different RSA methods appears justified. For translations, however, adjustments should be made to correct for differences in reference origin. Migration patterns of individual patients may differ as a result of distinct types of measurement error.
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Affiliation(s)
- Koen T van Hamersveld
- Department of Orthopaedics, Leiden University Medical Center, Leiden, the Netherlands; ,Correspondence:
| | | | - Lennard A Koster
- Department of Orthopaedics, Leiden University Medical Center, Leiden, the Netherlands;
| | - Rob G H H Nelissen
- Department of Orthopaedics, Leiden University Medical Center, Leiden, the Netherlands;
| | - Sören Toksvig-Larsen
- Department of Orthopaedics, Hässleholm Hospital, Hässleholm, Sweden and Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Bart L Kaptein
- Department of Orthopaedics, Leiden University Medical Center, Leiden, the Netherlands;
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Jacobsen A, Seehaus F, Hong Y, Cao H, Schuh A, Forst R, Sesselmann S. Model-based roentgen stereophotogrammetric analysis using elementary geometrical shape models: 10 years results of an uncemented acetabular cup component. BMC Musculoskelet Disord 2018; 19:335. [PMID: 30223820 PMCID: PMC6142331 DOI: 10.1186/s12891-018-2259-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 09/12/2018] [Indexed: 11/16/2022] Open
Abstract
Background Non-cemented acetabular cup components demonstrated different clinical performance depending on their surface texture or bearing couple. However, clinical osseointegration needs to be proved for each total joint arthroplasty (TJA) design. Aim of this study was to detect the in vivo migration pattern of a non-cemented cup design, using model-based roentgen stereophotogrammetric analysis with elementary geometrical shape models (EGS-RSA) to calculate early cup migration. Methods Interchangeable applicability of the model-based EGS-RSA method next to gold standard marker-based RSA method was assessed by clinical radiographs. Afterwards, in vivo acetabular cup migration for 39 patients in a maximum follow up of 120 months (10 years) was calculated using model-based EGS-RSA. Results For the axes with the best predictive capability for acetabular cup loosening, mean (±SD) values were calculated for migration and rotation of the cup. The cup migrated 0.16 (±0.22) mm along the cranio-caudal axis after 24 months and 0.36 (±0.72) mm after 120 months, respectively. It rotated − 0.61 (±0.57) deg. about the medio-lateral axis after 24 months and − 0.53 (±0.67) deg. after 120 months, respectively. Conclusions Interchangeable applicability of model-based EGS-RSA next to gold standard marker-based RSA method could be shown. Model-based EGS-RSA enables an in vivo migration measurement without the necessity of TJA specific surface models. Migration of the investigated acetabular cup component indicates significant migration values along all the three axes. However, migration values after the second postoperative year were within the thresholds reported in literature, indicating no risk for later aseptic component loosening of this TJA design.
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Affiliation(s)
- Anne Jacobsen
- Department of Orthopaedic Surgery, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Rathsberger Str. 57, 91054, Erlangen, Germany
| | - Frank Seehaus
- Department of Orthopaedic Surgery, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Rathsberger Str. 57, 91054, Erlangen, Germany
| | - Yutong Hong
- Department of Orthopaedic Surgery, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Rathsberger Str. 57, 91054, Erlangen, Germany
| | - Han Cao
- Department of Orthopaedic Surgery, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Rathsberger Str. 57, 91054, Erlangen, Germany
| | - Alexander Schuh
- Muskuloskelettales Zentrum, Klinikum Neumarkt, Nürnberger Str. 12, 92318, Neumarkt i. d. OPf, Germany
| | - Raimund Forst
- Department of Orthopaedic Surgery, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Rathsberger Str. 57, 91054, Erlangen, Germany
| | - Stefan Sesselmann
- Department of Orthopaedic Surgery, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Rathsberger Str. 57, 91054, Erlangen, Germany. .,Institute for Medical Technology, Ostbayerische Technische Hochschule Amberg-Weiden, Hetzenrichter Weg 15, 92637, Weiden, Germany.
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9
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Abstract
Purpose - We performed a systematic review and meta-analyses to evaluate the early and long-term migration patterns of tibial components of TKR of all known RSA studies. Methods - Migration pattern was defined as at least 2 postoperative RSA follow-up moments. Maximal total point motion (MTPM) at 6 weeks, 3 months, 6 months, 1 year, 2 years, 5 years, and 10 years were considered. Results - The literature search yielded 1,167 hits of which 53 studies were included, comprising 111 study groups and 2,470 knees. The majority of the early migration occurred in the first 6 months postoperatively followed by a period of stability, i.e., no or very little migration. Cemented and uncemented tibial components had different migration patterns. For cemented tibial components there was no difference in migration between all-poly and metal-backed components, between mobile bearing and fixed bearing, between cruciate retaining and posterior stabilized. Furthermore, no difference existed between TKR measured with model-based RSA or marker-based RSA methods. For uncemented TKR there was some variation in migration with the highest migration for uncoated TKR. Interpretation - The results from this meta-analysis on RSA migration of TKR are in line with both the survival analyses results from joint registries of these TKRs as well as revision rates results from meta-analyses, thus providing further proof for the association between early migration and late revision for loosening. The pooled migration patterns can be used both as benchmarks and for defining migration thresholds for future evaluation of new TKR.
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Affiliation(s)
- Bart G Pijls
- Department of Orthopaedics, Leiden University Medical Center, Leiden,Correspondence:
| | - José W M Plevier
- Walaeus Library, Leiden University Medical Center, Leiden, The Netherlands
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10
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Use of optical motion capture for the analysis of normative upper body kinematics during functional upper limb tasks: A systematic review. J Electromyogr Kinesiol 2018. [PMID: 29533202 DOI: 10.1016/j.jelekin.2018.02.011] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Quantifying three-dimensional upper body kinematics can be a valuable method for assessing upper limb function. Considering that kinematic model characteristics, performed tasks, and reported outcomes are not consistently standardized and exhibit significant variability across studies, the purpose of this review was to evaluate the literature investigating upper body kinematics in non-disabled individuals via optical motion capture. Specific objectives were to report on the kinematic model characteristics, performed functional tasks, and kinematic outcomes, and to assess whether kinematic protocols were assessed for validity and reliability. Five databases were searched. Studies using anatomical and/or cluster marker sets, along with optical motion capture, and presenting normative data on upper body kinematics were eligible for review. Information extracted included model characteristics, performed functional tasks, kinematic outcomes, and validity or reliability testing. 804 publication records were screened and 20 reviewed based on the selection criteria. Thirteen studies described their kinematic protocols adequately for reproducibility, and 8 studies followed International Society of Biomechanics standards for quantifying upper body kinematics. Six studies assessed their protocols for validity or reliability. While a substantial number of studies have adequately reported their protocols, more systematic work is needed to evaluate the validity and reliability of existing protocols.
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11
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Devane PA, Horne JG, Foley G, Stanley J. Measuring the migration of the components and polyethylene wear after total hip arthroplasty: beads and specialised radiographs are not necessary. Bone Joint J 2017; 99-B:1290-1297. [PMID: 28963149 DOI: 10.1302/0301-620x.99b10.bjj-2016-1169.r1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 06/13/2017] [Indexed: 01/27/2023]
Abstract
AIMS This paper describes the methodology, validation and reliability of a new computer-assisted method which uses models of the patient's bones and the components to measure their migration and polyethylene wear from radiographs after total hip arthroplasty (THA). MATERIALS AND METHODS Models of the patient's acetabular and femoral component obtained from the manufacturer and models of the patient's pelvis and femur built from a single computed tomography (CT) scan, are used by a computer program to measure the migration of the components and the penetration of the femoral head from anteroposterior and lateral radiographs taken at follow-up visits. The program simulates the radiographic setup and matches the position and orientation of the models to outlines of the pelvis, the acetabular and femoral component, and femur on radiographs. Changes in position and orientation reflect the migration of the components and the penetration of the femoral head. Validation was performed using radiographs of phantoms simulating known migration and penetration, and the clinical feasibility of measuring migration was assessed in two patients. RESULTS Migration of the acetabular and femoral components can be measured with limits of agreement (LOA) of 0.37 mm and 0.33 mm, respectively. Penetration of the femoral head can be measured with LOA of 0.161 mm. CONCLUSION The migration of components and polyethylene wear can be measured without needing specialised radiographs. Accurate measurement may allow earlier prediction of failure after THA. Cite this article: Bone Joint J 2017;99-B:1290-7.
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Affiliation(s)
- P A Devane
- Capital & Coast District Health Board, Private Bag 7902, Wellington South, New Zealand
| | - J G Horne
- Capital & Coast District Health Board, Private Bag 7902, Wellington South, New Zealand
| | - G Foley
- Capital & Coast District Health Board, Private Bag 7902, Wellington South, New Zealand
| | - J Stanley
- University of Otago, Wellington, P O Box 7343, Wellington South, New Zealand
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Stentz-Olesen K, Nielsen ET, De Raedt S, Jørgensen PB, Sørensen OG, Kaptein BL, Andersen MS, Stilling M. Validation of static and dynamic radiostereometric analysis of the knee joint using bone models from CT data. Bone Joint Res 2017; 6:376-384. [PMID: 28600383 PMCID: PMC5492337 DOI: 10.1302/2046-3758.66.bjr-2016-0113.r3] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 03/13/2017] [Indexed: 11/05/2022] Open
Abstract
Objectives Static radiostereometric analysis (RSA) using implanted markers is considered the most accurate system for the evaluation of prosthesis migration. By using CT bone models instead of markers, combined with a dynamic RSA system, a non-invasive measurement of joint movement is enabled. This method is more accurate than current 3D skin marker-based tracking systems. The purpose of this study was to evaluate the accuracy of the CT model method for measuring knee joint kinematics in static and dynamic RSA using the marker method as the benchmark. Methods Bone models were created from CT scans, and tantalum beads were implanted into the tibia and femur of eight human cadaver knees. Each specimen was secured in a fixture, static and dynamic stereoradiographs were recorded, and the bone models and marker models were fitted to the stereoradiographs. Results Results showed a mean difference between the two methods in all six degrees of freedom for static RSA to be within -0.10 mm/° and 0.08 mm/° with a 95% limit of agreement (LoA) ranging from ± 0.49 to 1.26. Dynamic RSA had a slightly larger range in mean difference of -0.23 mm/° to 0.16 mm/° with LoA ranging from ± 0.75 to 1.50. Conclusions In a laboratory-controlled setting, the CT model method combined with dynamic RSA may be an alternative to previous marker-based methods for kinematic analyses. Cite this article: K. Stentz-Olesen, E. T. Nielsen, S. De Raedt, P. B. Jørgensen, O. G. Sørensen, B. L. Kaptein, M. S. Andersen, M. Stilling. Validation of static and dynamic radiostereometric analysis of the knee joint using bone models from CT data. Bone Joint Res 2017;6:376–384. DOI: 10.1302/2046-3758.66.BJR-2016-0113.R3.
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Affiliation(s)
- K Stentz-Olesen
- Orthopaedic Research Group, Department of Orthopaedic Surgery, Aarhus University Hospital, Tage-Hansens Gade 2, Building 10A, Office 15, 8000 Aarhus C, Denmark
| | - E T Nielsen
- Orthopaedic Research Group, Department of Orthopaedic Surgery, Aarhus University Hospital, Tage-Hansens Gade 2, Building 10A, Office 15, 8000 Aarhus C, Denmark
| | - S De Raedt
- Nordisk Røntgen Teknik, Birkegårdsvej 16, 8361 Hesselager, Denmark
| | - P B Jørgensen
- Orthopaedic Research Group, Department of Orthopaedic Surgery, Aarhus University Hospital, Tage-Hansens Gade 2, Building 9A, 8000 Aarhus C, Denmark
| | - O G Sørensen
- Orthopaedic Research Group, Department of Orthopaedic Surgery, Aarhus University Hospital, Tage-Hansens Gade 2, Building 10A, Office 15, 8000 Aarhus C, Denmark
| | - B L Kaptein
- Biomechanics and Imaging Group, Department of Orthopaedic Surgery, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherland
| | - M S Andersen
- Department of Mechanical Engineering and Manufacturing, Aalborg University, Fibigerstræde 16, 9220 Aalborg East, Denmark
| | - M Stilling
- Orthopaedic Research Group, Departments of Orthopaedic Surgery and Clinical Medicine, Aarhus University Hospital, University of Aarhus, Tage-Hansens Gade 2, Building 10A, 8000 Aarhus C, Denmark
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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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Malak TT, Broomfield JAJ, Palmer AJR, Hopewell S, Carr A, Brown C, Prieto-Alhambra D, Glyn-Jones S. Surrogate markers of long-term outcome in primary total hip arthroplasty: A systematic review. Bone Joint Res 2016; 5:206-14. [PMID: 27267795 PMCID: PMC4921042 DOI: 10.1302/2046-3758.56.2000568] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 03/23/2016] [Indexed: 12/24/2022] Open
Abstract
Objectives High failure rates of metal-on-metal hip arthroplasty implants have highlighted the need for more careful introduction and monitoring of new implants and for the evaluation of the safety of medical devices. The National Joint Registry and other regulatory services are unable to detect failing implants at an early enough stage. We aimed to identify validated surrogate markers of long-term outcome in patients undergoing primary total hip arthroplasty (THA). Methods We conducted a systematic review of studies evaluating surrogate markers for predicting long-term outcome in primary THA. Long-term outcome was defined as revision rate of an implant at ten years according to National Institute of Health and Care Excellence guidelines. We conducted a search of Medline and Embase (OVID) databases. Separate search strategies were devised for the Cochrane database and Google Scholar. Each search was performed to include articles from the date of their inception to June 8, 2015. Results Our search strategy identified 1082 studies of which 115 studies were included for full article review. Following review, 17 articles were found that investigated surrogate markers of long-term outcome. These included one systematic review, one randomised control trial (RCT), one case control study and 13 case series. Validated surrogate markers included Radiostereometric Analysis (RSA) and Einzel-Bild-Röntgen-Analyse (EBRA), each measuring implant migration and wear. We identified five RSA studies (one systematic review and four case series) and four EBRA studies (one RCT and three case series). Patient Reported Outcome Measures (PROMs) at six months have been investigated but have not been validated against long-term outcomes. Conclusions This systematic review identified two validated surrogate markers of long-term primary THA outcome: RSA and EBRA, each measuring implant migration and wear. We recommend the consideration of RSA in the pre-market testing of new implants. EBRA can be used to investigate acetabular wear but not femoral migration. Further studies are needed to validate the use of PROMs for post-market surveillance. Cite this article: T. T. Malak, J. A. J. Broomfield, A. J. R. Palmer, S. Hopewell, A. Carr, C. Brown, D. Prieto-Alhambra, S. Glyn-Jones. Surrogate markers of long-term outcome in primary total hip arthroplasty: A systematic review. Bone Joint Res 2016;5:206–214. DOI: 10.1302/2046-3758.56.2000568.
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Affiliation(s)
- T T Malak
- Oxford NIHR Musculoskeletal Biomedical Research Unit, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Windmill Lane, Oxford OX3 7LD, UK
| | - J A J Broomfield
- Oxford NIHR Musculoskeletal Biomedical Research Unit, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Windmill Lane, Oxford OX3 7LD, UK
| | - A J R Palmer
- Oxford NIHR Musculoskeletal Biomedical Research Unit, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Windmill Lane, Oxford OX3 7LD, UK
| | - S Hopewell
- Oxford NIHR Musculoskeletal Biomedical Research Unit, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Windmill Lane, Oxford OX3 7LD, UK
| | - A Carr
- Oxford NIHR Musculoskeletal Biomedical Research Unit, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Windmill Lane, Oxford OX3 7LD, UK
| | - C Brown
- Oxford NIHR Musculoskeletal Biomedical Research Unit, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Windmill Lane, Oxford OX3 7LD, UK
| | - D Prieto-Alhambra
- Oxford NIHR Musculoskeletal Biomedical Research Unit, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Windmill Lane, Oxford OX3 7LD, UK
| | - S Glyn-Jones
- Oxford NIHR Musculoskeletal Biomedical Research Unit, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Windmill Lane, Oxford OX3 7LD, UK
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Mahato NK, Montuelle S, Cotton J, Williams S, Thomas J, Clark B. Development of a morphology-based modeling technique for tracking solid-body displacements: examining the reliability of a potential MRI-only approach for joint kinematics assessment. BMC Med Imaging 2016; 16:38. [PMID: 27189195 PMCID: PMC4870733 DOI: 10.1186/s12880-016-0140-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 05/03/2016] [Indexed: 11/25/2022] Open
Abstract
Background Single or biplanar video radiography and Roentgen stereophotogrammetry (RSA) techniques used for the assessment of in-vivo joint kinematics involves application of ionizing radiation, which is a limitation for clinical research involving human subjects. To overcome this limitation, our long-term goal is to develop a magnetic resonance imaging (MRI)-only, three dimensional (3-D) modeling technique that permits dynamic imaging of joint motion in humans. Here, we present our initial findings, as well as reliability data, for an MRI-only protocol and modeling technique. Methods We developed a morphology-based motion-analysis technique that uses MRI of custom-built solid-body objects to animate and quantify experimental displacements between them. The technique involved four major steps. First, the imaging volume was calibrated using a custom-built grid. Second, 3-D models were segmented from axial scans of two custom-built solid-body cubes. Third, these cubes were positioned at pre-determined relative displacements (translation and rotation) in the magnetic resonance coil and scanned with a T1 and a fast contrast-enhanced pulse sequences. The digital imaging and communications in medicine (DICOM) images were then processed for animation. The fourth step involved importing these processed images into an animation software, where they were displayed as background scenes. In the same step, 3-D models of the cubes were imported into the animation software, where the user manipulated the models to match their outlines in the scene (rotoscoping) and registered the models into an anatomical joint system. Measurements of displacements obtained from two different rotoscoping sessions were tested for reliability using coefficient of variations (CV), intraclass correlation coefficients (ICC), Bland-Altman plots, and Limits of Agreement analyses. Results Between-session reliability was high for both the T1 and the contrast-enhanced sequences. Specifically, the average CVs for translation were 4.31 % and 5.26 % for the two pulse sequences, respectively, while the ICCs were 0.99 for both. For rotation measures, the CVs were 3.19 % and 2.44 % for the two pulse sequences with the ICCs being 0.98 and 0.97, respectively. A novel biplanar imaging approach also yielded high reliability with mean CVs of 2.66 % and 3.39 % for translation in the x- and z-planes, respectively, and ICCs of 0.97 in both planes. Conclusions This work provides basic proof-of-concept for a reliable marker-less non-ionizing-radiation-based quasi-dynamic motion quantification technique that can potentially be developed into a tool for real-time joint kinematics analysis.
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Affiliation(s)
- Niladri K Mahato
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH, 45701, USA. .,Department of Biomedical Sciences, Ohio University, Athens, OH, 45701, USA.
| | - Stephane Montuelle
- Department of Biomedical Sciences, Ohio University, Athens, OH, 45701, USA
| | - John Cotton
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH, 45701, USA.,Department of Mechanical Engineering, Ohio University, Athens, OH, 45701, USA
| | - Susan Williams
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH, 45701, USA.,Department of Biomedical Sciences, Ohio University, Athens, OH, 45701, USA
| | - James Thomas
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH, 45701, USA.,School of Rehabilitation and Communication Sciences, Ohio University, Athens, OH, 45701, USA
| | - Brian Clark
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH, 45701, USA.,Department of Biomedical Sciences, Ohio University, Athens, OH, 45701, USA.,Department of Geriatric Medicine, Ohio University, Athens, OH, 45701, USA
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Seehaus F, Schwarze M, Flörkemeier T, von Lewinski G, Kaptein BL, Jakubowitz E, Hurschler C. Use of single-representative reverse-engineered surface-models for RSA does not affect measurement accuracy and precision. J Orthop Res 2016; 34:903-10. [PMID: 26553748 DOI: 10.1002/jor.23098] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 11/03/2015] [Indexed: 02/04/2023]
Abstract
Implant migration can be accurately quantified by model-based Roentgen stereophotogrammetric analysis (RSA), using an implant surface model to locate the implant relative to the bone. In a clinical situation, a single reverse engineering (RE) model for each implant type and size is used. It is unclear to what extent the accuracy and precision of migration measurement is affected by implant manufacturing variability unaccounted for by a single representative model. Individual RE models were generated for five short-stem hip implants of the same type and size. Two phantom analyses and one clinical analysis were performed: "Accuracy-matched models": one stem was assessed, and the results from the original RE model were compared with randomly selected models. "Accuracy-random model": each of the five stems was assessed and analyzed using one randomly selected RE model. "Precision-clinical setting": implant migration was calculated for eight patients, and all five available RE models were applied to each case. For the two phantom experiments, the 95%CI of the bias ranged from -0.28 mm to 0.30 mm for translation and -2.3° to 2.5° for rotation. In the clinical setting, precision is less than 0.5 mm and 1.2° for translation and rotation, respectively, except for rotations about the proximodistal axis (<4.1°). High accuracy and precision of model-based RSA can be achieved and are not biased by using a single representative RE model. At least for implants similar in shape to the investigated short-stem, individual models are not necessary. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:903-910, 2016.
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Affiliation(s)
- Frank Seehaus
- Laboratory for Biomechanics and Biomaterials, Hannover Medical School, Anna-von-Borries-Street 1-7, Hannover, 30625, Germany
| | - Michael Schwarze
- Laboratory for Biomechanics and Biomaterials, Hannover Medical School, Anna-von-Borries-Street 1-7, Hannover, 30625, Germany
| | - Thilo Flörkemeier
- Department of Orthopaedics, Hannover Medical School, Anna-von-Borries-Street 1-7, Hannover, 30625, Germany
| | - Gabriela von Lewinski
- Department of Orthopaedics, Hannover Medical School, Anna-von-Borries-Street 1-7, Hannover, 30625, Germany
| | - Bart L Kaptein
- Department of Orthopaedics, Division of Division of Image Processing, Department of Radiology, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Netherlands
| | - Eike Jakubowitz
- Laboratory for Biomechanics and Biomaterials, Hannover Medical School, Anna-von-Borries-Street 1-7, Hannover, 30625, Germany
| | - Christof Hurschler
- Laboratory for Biomechanics and Biomaterials, Hannover Medical School, Anna-von-Borries-Street 1-7, Hannover, 30625, Germany
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Patient-specific bone modeling and analysis: the role of integration and automation in clinical adoption. J Biomech 2014; 48:750-60. [PMID: 25547022 DOI: 10.1016/j.jbiomech.2014.12.018] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/26/2014] [Indexed: 12/11/2022]
Abstract
Patient-specific analysis of bones is considered an important tool for diagnosis and treatment of skeletal diseases and for clinical research aimed at understanding the etiology of skeletal diseases and the effects of different types of treatment on their progress. In this article, we discuss how integration of several important components enables accurate and cost-effective patient-specific bone analysis, focusing primarily on patient-specific finite element (FE) modeling of bones. First, the different components are briefly reviewed. Then, two important aspects of patient-specific FE modeling, namely integration of modeling components and automation of modeling approaches, are discussed. We conclude with a section on validation of patient-specific modeling results, possible applications of patient-specific modeling procedures, current limitations of the modeling approaches, and possible areas for future research.
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Madanat R, Mäkinen TJ, Aro HT, Bragdon C, Malchau H. Adherence of hip and knee arthroplasty studies to RSA standardization guidelines. A systematic review. Acta Orthop 2014; 85:447-55. [PMID: 24954489 PMCID: PMC4164860 DOI: 10.3109/17453674.2014.934187] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [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 Guidelines for standardization of radiostereometry (RSA) of implants were published in 2005 to facilitate comparison of outcomes between various research groups. In this systematic review, we determined how well studies have adhered to these guidelines. METHODS We carried out a literature search to identify all articles published between January 2000 and December 2011 that used RSA in the evaluation of hip or knee prosthesis migration. 2 investigators independently evaluated each of the studies for adherence to the 13 individual guideline items. Since some of the 13 points included more than 1 criterion, studies were assessed on whether each point was fully met, partially met, or not met. RESULTS 153 studies that met our inclusion criteria were identified. 61 of these were published before the guidelines were introduced (2000-2005) and 92 after the guidelines were introduced (2006-2011). The methodological quality of RSA studies clearly improved from 2000 to 2011. None of the studies fully met all 13 guidelines. Nearly half (43) of the studies published after the guidelines demonstrated a high methodological quality and adhered at least partially to 10 of the 13 guidelines, whereas less than one-fifth (11) of the studies published before the guidelines had the same methodological quality. Commonly unaddressed guideline items were related to imaging methodology, determination of precision from double examinations, and also mean error of rigid-body fitting and condition number cutoff levels. INTERPRETATION The guidelines have improved methodological reporting in RSA studies, but adherence to these guidelines is still relatively low. There is a need to update and clarify the guidelines for clinical hip and knee arthroplasty RSA studies.
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Affiliation(s)
- Rami Madanat
- Helsinki University Central Hospital, Helsinki,Harris Orthopaedic Laboratory, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | | | - Hannu T Aro
- Turku University Hospital and University of Turku, Turku, Finland
| | - Charles Bragdon
- Harris Orthopaedic Laboratory, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Henrik Malchau
- Harris Orthopaedic Laboratory, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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Li Y, Röhrl SM, Bøe B, Nordsletten L. Comparison of two different Radiostereometric analysis (RSA) systems with markerless elementary geometrical shape modeling for the measurement of stem migration. Clin Biomech (Bristol, Avon) 2014; 29:950-5. [PMID: 25175935 DOI: 10.1016/j.clinbiomech.2014.06.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 06/11/2014] [Accepted: 06/11/2014] [Indexed: 02/07/2023]
Abstract
UNLABELLED Radiostereometric analysis (RSA) is the gold standard of measurement for in vivo 3D implants migration. BACKGROUND The aim of this study was to evaluate the in vivo precision of 2 RSA marker-based systems compared with that of marker-free, elementary geometrical shape modeling RSA. METHODS Stem migration was measured in 50 patients recruited from an on-going Randomized Controlled Trial. We performed marker-based analysis with the Um RSA and RSAcore systems and compared these results with those of the elementary geometrical shape RSA. FINDINGS The precision for subsidence was 0.118 mm for Um RSA, 0.141 mm for RSAcore, and 0.136 mm for elementary geometrical shape RSA. The precision for retroversion was 1.3° for elementary geometrical shape RSA, approximately 2-fold greater than that for the other methods. The intraclass correlation coefficient between the marker-based systems and elementary geometrical shape RSA was approximately 0.5 for retroversion. All 3 methods yielded ICCs for subsidence and varus-valgus rotation above 0.9. DISCUSSION We found an excellent correlation between marker-based RSA and elementary geometrical shape RSA for subsidence and varus-valgus rotation, independent of the system used. The precisions for out-of-plane migration were inferior for elementary geometrical shape RSA. Therefore, as a mechanism of failure, retroversion may be more difficult to detect early. This is to our knowledge the first study to compare different RSA systems with or without markers on the implant. INTERPRETATION Marker-based RSA has high precision in all planes, independent of the system used. Elementary geometrical shape RSA is inferior in out-of-plane migration.
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Affiliation(s)
- Ye Li
- Department of Orthopedics, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Stephan M Röhrl
- Department of Orthopedics, Oslo University Hospital, Ullevål, Oslo, Norway.
| | - B Bøe
- Department of Orthopedics, Oslo University Hospital, Ullevål, Oslo, Norway
| | - Lars Nordsletten
- Department of Orthopedics, Oslo University Hospital, Ullevål, Oslo, Norway
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Brunkhorst JP, Giphart JE, LaPrade RF, Millett PJ. Coracohumeral Distances and Correlation to Arm Rotation: An In Vivo 3-Dimensional Biplane Fluoroscopy Study. Orthop J Sports Med 2013; 1:2325967113496059. [PMID: 26535235 PMCID: PMC4555485 DOI: 10.1177/2325967113496059] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background: Reduced coracohumeral distances have been reported to be associated with anterior shoulder disorders such as subscapularis tears, biceps tendon injuries, and leading edge supraspinatus tears. Purpose: To determine the variability in coracohumeral distance as a function of arm rotation in healthy male subjects. The null hypothesis was that no differences in coracohumeral distance would exist with respect to arm rotation. Study Design: Descriptive laboratory study. Methods: A total of 9 male participants who had full range of motion, strength, and no prior surgery or symptoms in their tested shoulders were enrolled in this institutional review board–approved study. Computed tomography scans of the shoulder were obtained for each subject. A dynamic biplane fluoroscopy system recorded internal and external shoulder rotation with the arm held in the neutral position. Three-dimensional reconstructions of each motion were generated, and the coracohumeral distance and coracoid index (lateral extension of the coracoid) were measured. Results: The mean coracohumeral distance in neutral rotation was 12.7 ± 2.1 mm. A significantly shorter minimum coracohumeral distance of 10.6 ± 1.8 mm was achieved (P = .001) at a mean glenohumeral joint internal rotation angle of 36.6° ± 19.2°. This corresponded to a reduction in coracohumeral distance of 16.4% (range, 6.6%-29.8%). The mean coracoid index was 14.2 ± 6.8 mm. A moderate correlation (R = −0.75) existed between the coracohumeral distance and coracoid index. Conclusion: Coracohumeral distance was reduced during internal rotation. Decreased coracohumeral distance was correlated with larger coracoid indices. Clinical Relevance: This study provides a reference value for coracohumeral distance in the healthy male population. Knowledge of how coracohumeral distance varies over the range of arm internal-external rotation may improve the clinical diagnosis and treatment plan for patients with anterior shoulder pathology, specifically subcoracoid impingement. Imaging of the coracohumeral distance during internal rotation with the hand at approximately midline should be considered to assess patients with anterior shoulder pain.
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Affiliation(s)
- John P Brunkhorst
- Department of BioMedical Engineering, Steadman Philippon Research Institute, Vail, Colorado, USA
| | - J Erik Giphart
- Department of BioMedical Engineering, Steadman Philippon Research Institute, Vail, Colorado, USA
| | - Robert F LaPrade
- Department of BioMedical Engineering, Steadman Philippon Research Institute, Vail, Colorado, USA. ; The Steadman Clinic, Vail, Colorado, USA
| | - Peter J Millett
- Department of BioMedical Engineering, Steadman Philippon Research Institute, Vail, Colorado, USA. ; The Steadman Clinic, Vail, Colorado, USA
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Seehaus F, Emmerich J, Kaptein BL, Windhagen H, Hurschler C. Dependence of model-based RSA accuracy on higher and lower implant surface model quality. Biomed Eng Online 2013; 12:32. [PMID: 23587251 PMCID: PMC3637620 DOI: 10.1186/1475-925x-12-32] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Accepted: 04/12/2013] [Indexed: 11/10/2022] Open
Abstract
Background Model-based Roentgen Stereophotogrammetric Analysis (MBRSA) allows the accurate in vivo measurement of the relative motion between an implant and the surrounding bone (migration), using pose-estimation algorithms and three dimensional geometric surface models of the implant. The goal of this study was thus to investigate the effect of surface model resolution on the accuracy of the MBRSA method. Methods Four different implant geometries (knee femoral and tibial components, and two different hip stems) were investigated, for each of which two reversed engineering (RE) models of differing spatial digitizing resolution were generated. Accuracy of implant migration measurement using MBRSA was assessed in dependence on surface model resolution using an experimental phantom-model set up. Results When using the lower quality RE models, the worst bias observed ranged from -0.048 to 0.037 mm, and -0.057 to 0.078 deg for translation and rotation respectively. For higher quality reverse engineering models, bias ranged from -0.042 to 0.048 mm, and -0.449 to 0.029 deg. The pair-wise comparisons of digitizing resolution (higher vs. lower quality) within the different implant type revealed significant differences only for the hip stems (p < 0.001). Conclusion The data suggest that the application of lower resolution RE models for MBRSA is a viable alternative method for the in vivo measurement of implant migration, in particular for implants with non symmetrical geometries (total knee arthroplasty). Implants with larger length to width aspect ratio (total hip arthroplasty) may require high resolution RE models in order to achieve acceptable accuracy. Conversely, for some axis the bias for translation are clearly worse for translation, and are marginally better for rotations using the lower resolution RE models instead of the higher ones. However, performed box plots ranges were well within what has been reported in the literature. The observed lower accuracy and precision of the measurements for hip stem components for rotations about the superior-inferior direction is presumably the result of the nature of the MBRSA method. This well known effect within MBRSA for rotations about the axis of symmetry of axially-symmetric objects do not change the contour of the projected image to as large a degree as motion about a non-symmetric axes. It is not possible to detected this small motion as accurately using pose-estimation methods. This may affect the “higher” accuracy for the applied lower resolution RE models.
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Giphart JE, Brunkhorst JP, Horn NH, Shelburne KB, Torry MR, Millett PJ. Effect of plane of arm elevation on glenohumeral kinematics: a normative biplane fluoroscopy study. J Bone Joint Surg Am 2013; 95:238-45. [PMID: 23389787 DOI: 10.2106/jbjs.j.01875] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Understanding glenohumeral motion in normal and pathologic states requires the precise measurement of shoulder kinematics. The effect of the plane of arm elevation on glenohumeral translations and rotations remains largely unknown. The purpose of this study was to measure the three-dimensional glenohumeral translations and rotations during arm elevation in healthy subjects. METHODS Eight male subjects performed scaption and forward flexion, and five subjects (three men and two women) performed abduction, inside a dynamic biplane fluoroscopy system. Bone geometries were extracted from computed tomography images and used to determine the three-dimensional position and orientation of the humerus and scapula in individual frames. Descriptive statistics were determined for glenohumeral joint rotations and translations, and linear regressions were performed to calculate the scapulohumeral rhythm ratio. RESULTS The scapulohumeral rhythm ratio was 2.0 ± 0.4:1 for abduction, 1.6 ± 0.5:1 for scaption, and 1.1 ± 0.3:1 for forward flexion, with the ratio for forward flexion being significantly lower than that for abduction (p = 0.002). Humeral head excursion was largest in abduction (5.1 ± 1.1 mm) and smallest in scaption (2.4 ± 0.6 mm) (p < 0.001). The direction of translation, as determined by the linear regression slope, was more inferior during abduction (-2.1 ± 1.8 mm/90°) compared with forward flexion (0.1 ± 10.9 mm/90°) (p = 0.024). CONCLUSIONS Scapulohumeral rhythm significantly decreased as the plane of arm elevation moved in an anterior arc from abduction to forward flexion. The amount of physiologic glenohumeral excursion varied significantly with the plane of elevation, was smallest for scaption, and showed inconsistent patterns across subjects with the exception of consistent inferior translation during abduction.
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Affiliation(s)
- J Erik Giphart
- Department of BioMedical Engineering, Steadman Philippon Research Institute, 181 West Meadow Drive, Suite 1000, Vail, CO 81657, USA
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Tersi L, Barré A, Fantozzi S, Stagni R. In vitro quantification of the performance of model-based mono-planar and bi-planar fluoroscopy for 3D joint kinematics estimation. Med Biol Eng Comput 2012; 51:257-65. [DOI: 10.1007/s11517-012-0987-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 10/29/2012] [Indexed: 10/27/2022]
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Giphart JE, van der Meijden OAJ, Millett PJ. The effects of arm elevation on the 3-dimensional acromiohumeral distance: a biplane fluoroscopy study with normative data. J Shoulder Elbow Surg 2012; 21:1593-600. [PMID: 22361718 DOI: 10.1016/j.jse.2011.11.023] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Revised: 11/10/2011] [Accepted: 11/14/2011] [Indexed: 02/01/2023]
Abstract
HYPOTHESIS AND BACKGROUND Narrowing of the subacromial space has been implicated in several shoulder pathologies. However, the location of the minimum distance points during clinical testing has not been defined. We sought to measure the in vivo minimum distance and location of the minimum distance points on the acromion and proximal humerus during arm elevation. METHODS Eight healthy male subjects (mean age, 30 years) underwent a dynamic in vivo biplane fluoroscopy assessment of scaption and forward elevation. For each frame, the 3-dimensional position and orientation of the humerus and scapula were determined, and the acromiohumeral distance (AHD) was measured as the shortest distance between the acromion and proximal humerus. RESULTS The minimum AHD was 2.6 ± 0.8 mm during scaption and 1.8 ± 1.2 mm during forward flexion at elevation angles of 83° ± 13° and 97° ± 23°, respectively. The minimum distance point was located on the articular surface of the humeral head from the neutral arm position until 34° ± 8° for scaption and 36° ± 6° for forward flexion. Upon further elevation, the minimum distance point was located within the footprint of the supraspinatus muscle until 72° ± 12° for scaption and 65° ± 8° for forward flexion. At greater elevation angles, the minimum distance points were between the acromion and the proximal humeral shaft, distal from the greater tuberosity. CONCLUSIONS The shortest AHD was at approximately 90° of arm elevation. The AHD was no longer measured intra-articularly or within the supraspinatus footprint above approximately 70° of arm elevation.
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Affiliation(s)
- J Erik Giphart
- Biomechanics Research Department, Steadman Philippon Research Institute, Vail, CO 81657, USA
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Dunbar MJ, Fong JW, Wilson DA, Hennigar AW, Francis PA, Glazebrook MA. Longitudinal migration and inducible displacement of the Mobility Total Ankle System. Acta Orthop 2012; 83:394-400. [PMID: 22880712 PMCID: PMC3427631 DOI: 10.3109/17453674.2012.712890] [Citation(s) in RCA: 17] [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 RSA can be used for early detection of unstable implants. We assessed the micromotion of the Mobility Total Ankle System over 2 years, to evaluate the stability of the bone-implant interface using radiostereometric analysis measurements of longitudinal migration and inducible displacement. PATIENTS AND METHODS 23 patients were implanted with the Mobility system. Median age was 62 (28-75) years and median BMI was 28.8 (26.0-34.5). Supine radiostereometric analysis examinations were done from postoperatively to the 2-year follow-up. Standing examinations were taken from the 3-month to the 2-year follow-up. Migrations and displacements were assessed using model-based RSA software (v. 3.2). RESULTS The median maximum total point motion (MTPM) for the implants at 2 years was 1.19 (0.39-1.95) mm for the talar component and 0.90 (0.17-2.28) mm for the spherical tip of the tibial component. The general pattern for all patients was that the slope of the migration curves decreased over time. The main direction of motion for both components was that of subsidence. The median 2-year MTPM inducible displacement for the talar component was 0.49 (0.27-1.15) mm, and it was 0.07 (0.03-0.68) mm for the tibial component tip. INTERPRETATION The implants subside into the bone over time and under load. This corresponds to the direction of primary loading during standing or walking. This statistically significant motion may become a clinically significant finding that would correspond with premature implant failure.
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Affiliation(s)
- Michael J Dunbar
- Division of Orthopaedics, Department of Surgery,School of Biomedical Engineering, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Jason W Fong
- School of Biomedical Engineering, Dalhousie University, Halifax, Nova Scotia, Canada
| | | | | | | | - Mark A Glazebrook
- Division of Orthopaedics, Department of Surgery,School of Biomedical Engineering, Dalhousie University, Halifax, Nova Scotia, Canada
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Stilling M, Kold S, de Raedt S, Andersen NT, Rahbek O, Søballe K. Superior accuracy of model-based radiostereometric analysis for measurement of polyethylene wear: A phantom study. Bone Joint Res 2012; 1:180-91. [PMID: 23610688 PMCID: PMC3626226 DOI: 10.1302/2046-3758.18.2000041] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Accepted: 06/29/2012] [Indexed: 12/17/2022] Open
Abstract
Objectives The accuracy and precision of two new methods of model-based
radiostereometric analysis (RSA) were hypothesised to be superior
to a plain radiograph method in the assessment of polyethylene (PE)
wear. Methods A phantom device was constructed to simulate three-dimensional
(3D) PE wear. Images were obtained consecutively for each simulated
wear position for each modality. Three commercially available packages
were evaluated: model-based RSA using laser-scanned cup models (MB-RSA),
model-based RSA using computer-generated elementary geometrical
shape models (EGS-RSA), and PolyWare. Precision (95% repeatability
limits) and accuracy (Root Mean Square Errors) for two-dimensional
(2D) and 3D wear measurements were assessed. Results The precision for 2D wear measures was 0.078 mm, 0.102 mm, and
0.076 mm for EGS-RSA, MB-RSA, and PolyWare, respectively. For the
3D wear measures the precision was 0.185 mm, 0.189 mm, and 0.244
mm for EGS-RSA, MB-RSA, and PolyWare respectively. Repeatability
was similar for all methods within the same dimension, when compared between
2D and 3D (all p > 0.28). For the 2D RSA methods, accuracy was below
0.055 mm and at least 0.335 mm for PolyWare. For 3D measurements,
accuracy was 0.1 mm, 0.2 mm, and 0.3 mm for EGS-RSA, MB-RSA and
PolyWare respectively. PolyWare was less accurate compared with
RSA methods (p = 0.036). No difference was observed between the
RSA methods (p = 0.10). Conclusions For all methods, precision and accuracy were better in 2D, with
RSA methods being superior in accuracy. Although less accurate and
precise, 3D RSA defines the clinically relevant wear pattern (multidirectional).
PolyWare is a good and low-cost alternative to RSA, despite being
less accurate and requiring a larger sample size.
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Affiliation(s)
- M Stilling
- Aarhus University Hospital, Department of Orthopaedics, Tage-Hansens Gade 2, 8000 Aarhus C, Denmark
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Markerless Roentgen Stereophotogrammetric Analysis for in vivo implant migration measurement using three dimensional surface models to represent bone. J Biomech 2012; 45:1540-5. [PMID: 22465625 DOI: 10.1016/j.jbiomech.2012.03.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Revised: 01/31/2012] [Accepted: 03/02/2012] [Indexed: 11/23/2022]
Abstract
Recent studies have shown that model-based RSA using implant surface models to detect in vivo migration is as accurate as the classical marker-based RSA method. Use of bone surface models would be a further advancement of the model-based method by decreasing complications arising from marker insertion. The aim of this pilot investigation was to assess the feasibility of a "completely markerless" model-based RSA in detecting migration of an implant using bone surface models instead of bone markers. A total knee arthroplasty (TKA) was performed on a human cadaver knee, which was subsequently investigated by repeated RSA measurements performed by one observer. The cadaver knee was CT scanned prior to implantation of the TKA. Tibia-fibular surface models were created using two different commercially available software packages to investigate the effect of segmentation software on the accuracy of repeated migration measures of zero displacement by one observer. Reverse engineered surface models of the TKA tibial component were created. The analysis of the RSA images was repeated 10 times by one individual observer. For the markerless method, the greatest apparent migration observed about the three anatomical axes investigated was between -2.08 and 1.35 mm (SD ≤ 0.88) for z-axis translation, and -4.57° to 7.86° (SD ≤ 3.17) for R(y)-axis rotation, which were well beyond out of the range of what is typically considered adequate for clinically relevant RSA measurements. Use of tibia-fibular surface models of the bone instead of markers could provide practical advantages in evaluating implant migration. However, we found the accuracy and precision of the markerless approach to be lower than that of marker-based RSA, to a degree which precludes the use of this method for measuring implant migration in its present form.
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Syu CB, Lin SC, Huang CY, Lai JY, Shih KS, Chen KJ. Improved execution efficiency of model-based roentgen stereophotogrammetric analysis: simplification and segmentation of model meshes. Comput Methods Biomech Biomed Engin 2012; 15:1347-57. [PMID: 22401491 DOI: 10.1080/10255842.2011.597352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Recently, the model-based roentgen stereophotogrammetric analysis (RSA) method has been developed as an in vivo tool to estimate static pose and dynamic motion of the instrumented prostheses. The two essential inputs for the RSA method are prosthetic models and roentgen images. During RSA calculation, the implants are often reversely scanned and input in the form of meshes to estimate the outline error between prosthetic projection and roentgen images. However, the execution efficiency of the RSA iterative calculation may limit its clinical practicability, and one reason for inefficiency may be very large number of meshes in the model. This study uses two methods of mesh manipulation to improve the execution efficiency of RSA calculation. The first is to simplify the model meshes and the other is to segment and delete the meshes of insignificant regions. An index (i.e. critical percentage) of an optimal element number is defined as the trade-off between execution efficiency and result accuracy. The predicted results are numerically validated by total knee prosthetic system. The outcome shows that the optimal strategy of the mesh manipulation is simplification and followed by segmentation. On average, the element number can even be reduced to 1% of the original models. After the mesh manipulation, the execution efficiency can be increased about 75% without compromising the accuracy of the predicted RSA results (the increment of rotation and translation error: 0.06° and 0.02 mm). In conclusion, prosthetic models should be manipulated by simplification and segmentation methods prior to the RSA calculation to increase the execution efficiency and then to improve clinical applicability of the RSA method.
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Affiliation(s)
- Ci-Bin Syu
- Department of Mechanical Engineering, National Central University, Taoyuan, Taiwan
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Giphart JE, Elser F, Dewing CB, Torry MR, Millett PJ. The long head of the biceps tendon has minimal effect on in vivo glenohumeral kinematics: a biplane fluoroscopy study. Am J Sports Med 2012; 40:202-12. [PMID: 21965188 DOI: 10.1177/0363546511423629] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND The in vivo stabilizing role of the long head of the biceps tendon (LHB) is poorly understood. While cadaveric studies report that the loaded LHB constrains translations in all directions, clinical data suggest that there is no clinically demonstrable alteration in glenohumeral position after LHB tenodesis or tenotomy. The purpose of this study was to investigate potential alterations in glenohumeral kinematics after LHB tenodesis during 3 dynamic in vivo motions using a biplane fluoroscopy system. HYPOTHESIS Our hypothesis was that there would be no difference in glenohumeral translations greater than 1.0 mm between shoulders after biceps tenodesis and healthy contralateral shoulders. STUDY DESIGN Controlled laboratory study. METHODS Five patients who underwent unilateral, open subpectoral tenodesis performed abduction, a simulated late cocking phase of a throw, and simulated lifting with both their tenodesed shoulder and their contralateral healthy shoulder inside a biplane fluoroscopy system. Dynamic 3-dimensional glenohumeral positions and electromyography activity of the biceps brachii muscle were determined and compared. RESULTS Significant glenohumeral translations occurred in both shoulders for abduction (3.4 mm inferiorly; P < .01) and simulated late cocking (2.6 mm anteriorly; P < .01). The mean difference for each motion in glenohumeral position between the tenodesed and the contralateral healthy shoulders was always less than 1.0 mm. The tenodesed shoulders were more anterior (centered) during abduction (0.7 mm; P < .01) and for the eccentric phase of the simulated late cocking motion (0.9 mm; P < .02). No significant differences were found during the simulated lifting motion and in the superior-inferior direction. CONCLUSION The effect of biceps tenodesis on glenohumeral position during the motions studied in vivo was minimal compared with physiological translations and interpatient variability. CLINICAL RELEVANCE Our findings demonstrated that LHB tenodesis does not dramatically alter glenohumeral position during dynamic motions, suggesting the risk for clinically significant alterations in glenohumeral kinematics after tenodesis is low in otherwise intact shoulders.
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Affiliation(s)
- J Erik Giphart
- Steadman Philippon Research Institute, Vail, CO 81657, USA.
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Myers CA, Torry MR, Shelburne KB, Giphart JE, LaPrade RF, Woo SLY, Steadman JR. In vivo tibiofemoral kinematics during 4 functional tasks of increasing demand using biplane fluoroscopy. Am J Sports Med 2012; 40:170-8. [PMID: 21997729 DOI: 10.1177/0363546511423746] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND The anterior cruciate ligament (ACL) has been well defined as the main passive restraint to anterior tibial translation (ATT) in the knee and plays an important role in rotational stability. However, it is unknown how closely the ACL and other passive and active structures of the knee constrain translations and rotations across a set of functional activities of increasing demand on the quadriceps. HYPOTHESIS Anterior tibial translation and internal rotation of the tibia relative to the femur would increase as the demand on the quadriceps increased. STUDY DESIGN Controlled laboratory study. METHODS The in vivo 3-dimensional knee kinematics of 10 adult female patients (height, 167.8 ± 7.1 cm; body mass, 57 ± 4 kg; body mass index [BMI], 24.8 ± 1.7 kg/m(2); age, 29.7 ± 7.9 years) was measured using biplane fluoroscopy while patients completed 4 functional tasks. The tasks included an unloaded knee extension in which the patient slowly extended the knee from 90° to 0° of flexion in 2 seconds; walking at a constant pace of 90 steps per minute; a maximum effort isometric knee extension with the knee at 70° of flexion; and landing from a height of 40 cm in which the patient stepped off a box, landed, and immediately performed a maximum effort vertical jump. RESULTS Landing (5.6 ± 1.9 mm) produced significantly greater peak ATT than walking (3.1 ± 2.2 mm) and unweighted full extension (2.6 ± 2.1 mm) (P < .01), but there was no difference between landing and a maximum isometric contraction (5.0 ± 1.9 mm). While there was no significant difference in peak internal rotation between landing (19.4° ± 5.7°), maximum isometric contraction (15.9° ± 6.7°), and unweighted full knee extension (14.5° ± 7.7°), each produced significantly greater internal rotation than walking (3.9° ± 4.2°) (P < .001). Knee extension torque significantly increased for each task (P < .01): unweighted knee extension (4.7 ± 1.2 N·m), walking (36.5 ± 7.9 N·m), maximum isometric knee extension (105.1 ± 8.2 N·m), and landing (140.2 ± 26.2 N·m). CONCLUSION Anterior tibial translations significantly increased as demand on the quadriceps and external loading increased. Internal rotation was not significantly different between landing, isometric contraction, and unweighted knee extension. Additionally, ATT and internal rotation from each motion were within the normal range, and no excessive amounts of translation or rotation were observed. CLINICAL RELEVANCE This study demonstrated that while ATT will increase as demand on the quadriceps and external loading increases, the knee is able to effectively constrain ATT and internal rotation. This suggests that the healthy knee has a safe envelope of function that is tightly controlled even though task demand is elevated.
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Affiliation(s)
- Casey A Myers
- Biomechanics Research Laboratory, Steadman Philippon Research Institute, Vail, Colorado, USA
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Torry MR, Myers C, Shelburne KB, Peterson D, Giphart JE, Pennington WW, Krong JP, Woo SLY, Steadman JR. Relationship of knee shear force and extensor moment on knee translations in females performing drop landings: a biplane fluoroscopy study. Clin Biomech (Bristol, Avon) 2011; 26:1019-24. [PMID: 21820780 PMCID: PMC3375210 DOI: 10.1016/j.clinbiomech.2011.06.010] [Citation(s) in RCA: 18] [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: 07/15/2010] [Revised: 06/21/2011] [Accepted: 06/22/2011] [Indexed: 02/07/2023]
Abstract
BACKGROUND Research has linked knee extensor moment and knee shear force to the non-contact anterior cruciate ligament injury during the landing motion. However, how these biomechanical performance factors relate to knee translations in vivo is not known as knee translations cannot be obtained with traditional motion capture techniques. The purpose of this study was to combine traditional motion capture with high-speed, biplane fluoroscopy imaging to determine relationships between knee extensor moment and knee shear force profiles with anterior and lateral tibial translations occurring during drop landing in female athletes. METHODS 15 females performed drop landings from a height of 40 cm while being recorded using a high speed, biplane fluoroscopy system and simultaneously being recorded using surface marker motion capture techniques to estimate knee joint angle, reaction force and moment profiles. FINDINGS No significant statistical relationships were observed between peak anterior or posterior knee shear force and peak anterior and lateral tibial translations; or, between peak knee extensor moment and peak anterior and lateral tibial translations. Although differences were noted in peak shear force (P=0.02) and peak knee extensor moment (P<0.001) after stratification into low and high shear force and moment cohorts, no differences were noted in anterior and lateral tibial translations (all P ≥ 0.18). INTERPRETATION Females exhibiting high knee extensor moment and knee shear force during drop landings do not yield correspondingly high anterior and lateral tibial translations.
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Affiliation(s)
- Michael R Torry
- School of Kinesiology and Recreation, Illinois State University, Normal, IL 61761-0512, USA.
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Myers CA, Torry MR, Peterson DS, Shelburne KB, Giphart JE, Krong JP, Woo SLY, Steadman JR. Measurements of tibiofemoral kinematics during soft and stiff drop landings using biplane fluoroscopy. Am J Sports Med 2011; 39:1714-22. [PMID: 21602566 PMCID: PMC4167636 DOI: 10.1177/0363546511404922] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Previous laboratory studies of landing have defined landing techniques in terms of soft or stiff landings according to the degree of maximal knee flexion angle attained during the landing phase and the relative magnitude of the ground-reaction force. Current anterior cruciate ligament injury prevention programs are instructing athletes to land softly to avoid excessive strain on the anterior cruciate ligament. PURPOSE This study was undertaken to measure, describe, and compare tibiofemoral rotations and translations of soft and stiff landings in healthy individuals using biplane fluoroscopy. STUDY DESIGN Controlled laboratory study. METHODS The in vivo, lower extremity, 3-dimensional knee kinematics of 16 healthy adults (6 male and 10 female) instructed to land softly and stiffly in different trials were collected in biplane fluoroscopy as they performed the landing from a height of 40 cm. RESULTS Average and maximum relative anterior tibial translation (average, 2.8 ± 1.2 mm vs 3.0 ± 1.4 mm; maximum, 4.7 ± 1.6 mm vs 4.4 ± 0.8 mm), internal/external rotation (average, 3.7° ± 5.1° vs 2.7° ± 4.3°; maximum, 5.6° ± 5.5° vs 4.9° ± 4.7°), and varus/valgus (average, 0.2° ± 1.2° vs 0.2° ± 1.0°; maximum, 1.7° ± 1.2° vs 1.6° ± 0.9°) were all similar between soft and stiff landings, respectively. The peak vertical ground-reaction force was significantly larger for stiff landings than for soft landings (2.60 ± 1.32 body weight vs 1.63 ± 0.73; P < .001). The knee flexion angle total range of motion from the minimum angle at contact to the maximum angle at peak knee flexion was significantly greater for soft landings than for stiff (55.4° ± 8.8° vs 36.8° ± 11.1°; P < .01). CONCLUSION Stiff landings, as defined by significantly lower knee flexion angles and significantly greater peak ground-reaction forces, do not result in larger amounts of anterior tibial translation or knee rotation in either varus/valgus or internal/external rotation in healthy individuals. CLINICAL RELEVANCE In healthy knees, the musculature and soft tissues of the knee are able to maintain translations and rotations within a small, safe range during controlled landing tasks of differing demand. The knee kinematics of this healthy population will serve as a comparison for injured knees in future studies. It should be stressed that because the authors did not compare how the loads were distributed over the soft tissues of the knee between the 2 landing styles, the larger ground-reaction forces and more extended knee position observed during stiff landings should still be considered dangerous to the anterior cruciate ligament and other structures of the lower extremities, particularly in competitive settings where movements are often unanticipated.
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Affiliation(s)
- Casey A. Myers
- Biomechanics Research Department, Steadman Philippon Research Institute, Vail, Colorado.,Department of Mechanical and Materials Engineering, The University of Denver, Denver, Colorado
| | - Michael R. Torry
- Biomechanics Research Department, Steadman Philippon Research Institute, Vail, Colorado.,School of Kinesiology and Recreation, Illinois State University, Normal, Illinois
| | - Daniel S. Peterson
- Biomechanics Research Department, Steadman Philippon Research Institute, Vail, Colorado
| | - Kevin B. Shelburne
- Department of Mechanical and Materials Engineering, The University of Denver, Denver, Colorado
| | - J. Erik Giphart
- Biomechanics Research Department, Steadman Philippon Research Institute, Vail, Colorado
| | - Jacob P. Krong
- Biomechanics Research Department, Steadman Philippon Research Institute, Vail, Colorado
| | - Savio L-Y. Woo
- Musculoskeletal Research Center, Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - J. Richard Steadman
- Biomechanics Research Department, Steadman Philippon Research Institute, Vail, Colorado.,Address correspondence to J. Richard Steadman, MD, Steadman Philippon Research Institute, 181 West Meadow Drive, Suite 1000, Vail, CO 81657 ()
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Torry MR, Shelburne KB, Peterson DS, Giphart JE, Krong JP, Myers C, Steadman JR, Woo SLY. Knee kinematic profiles during drop landings: a biplane fluoroscopy study. Med Sci Sports Exerc 2011; 43:533-41. [PMID: 20689456 DOI: 10.1249/mss.0b013e3181f1e491] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
INTRODUCTION The six degrees of freedom knee motion during dynamic activities is not well understood. PURPOSE Biplane fluoroscopy was used to measure the three-dimensional rotations and translations of healthy knees during stiff drop landings and to determine the relationships between three-dimensional rotations and anterior (ATT) and lateral tibial translations (LTT). METHODS Six males performed stiff drop landings from 40 cm while being filmed using a high-speed, biplane fluoroscopy system. Initial, peak, and excursions for rotations and translations were calculated, and relationships and changes in these variables were assessed (α = 0.05). RESULTS Knee flexion at contact was 13.9° ± 9.2° (mean ± SD) and increased to a peak of 44.0° ± 17.2° with an excursion of 31.5° ± 14.1°. Knee varus/valgus angle at contact was -0.3° ± 1.8° varus; subjects progressed into a mean peak valgus position of 1.5° ± 0.9° with total excursion of 2.5° ± 0.9°. Four of six subjects landed externally rotated (2.5° ± 3.0°); two landed internally rotated (-4.9° ± 1.5°), yielding a contact angle of -2.4° ± 3.0° of internal rotation, a peak internal rotation of -5.5° ± 6.0°, and excursion of 3.1° ± 5.5°. Peak ATT were 4.3 ± 0.7 mm (excursion = 2.1 ± 0.9 mm), occurring within 50 ms after contact. Peak LTT were 1.5 ± 1.4 mm (excursion = 2.6 ± 1.6 mm). Significant regressions were found between ATT and knee valgus angle (r2 = 0.39, P = 0.006), between LTT and internal rotation (r2 = 0.96, P < 0.0001), and between LTT and knee valgus angle (quadratic, r2 = 0.90, P < 0.0001). CONCLUSION This study provides a direct correlation between knee valgus angle with knee ATT and LTT during drop landings.
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Affiliation(s)
- Michael R Torry
- Biomechanics Research Laboratory, Steadman Philippon Research Institute, Vail, CO, USA.
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Dual mobility hip arthroplasty wear measurement: Experimental accuracy assessment using radiostereometric analysis (RSA). Orthop Traumatol Surg Res 2010; 96:609-15. [PMID: 20655819 DOI: 10.1016/j.otsr.2010.04.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2009] [Revised: 03/29/2010] [Accepted: 04/13/2010] [Indexed: 02/02/2023]
Abstract
INTRODUCTION The use of dual mobility cups is an effective method to prevent dislocations. However, the specific design of these implants can raise the suspicion of increased wear and subsequent periprosthetic osteolysis. HYPOTHESIS Using radiostereometric analysis (RSA), migration of the femoral head inside the cup of a dual mobility implant can be defined to apprehend polyethylene wear rate. STUDY OBJECTIVES The study aimed to establish the precision of RSA measurement of femoral head migration in the cup of a dual mobility implant, and its intra- and interobserver variability. MATERIAL AND METHODS A total hip prosthesis phantom was implanted and placed under weight loading conditions in a simulator. Model-based RSA measurement of implant penetration involved specially machined polyethylene liners with increasing concentric wear (no wear, then 0.25, 0.5 and 0.75mm). Three examiners, blinded to the level of wear, analyzed (10 times) the radiostereometric films of the four liners. There was one experienced, one trained, and one inexperienced examiner. Statistical analysis measured the accuracy, precision, and intra- and interobserver variability by calculating Root Mean Square Error (RMSE), Concordance Correlation Coefficient (CCC), Intra Class correlation Coefficient (ICC), and Bland-Altman plots. RESULTS Our protocol, that used a simple geometric model rather than the manufacturer's CAD files, showed precision of 0.072mm and accuracy of 0.034mm, comparable with machining tolerances with low variability. Correlation between wear measurement and true value was excellent with a CCC of 0.9772. Intraobserver reproducibility was very good with an ICC of 0.9856, 0.9883 and 0.9842, respectively for examiners 1, 2 and 3. Interobserver reproducibility was excellent with a CCC of 0.9818 between examiners 2 and 1, and 0.9713 between examiners 3 and 1. DISCUSSION Quantification of wear is indispensable for the surveillance of dual mobility implants. This in vitro study validates our measurement method. Our results, and comparison with other studies using different measurement technologies (RSA, standard radiographs, Martell method) make model-based RSA the reference method for measuring the wear of total hip prostheses in vivo. LEVEL OF EVIDENCE Level 3. Prospective diagnostic study.
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Hansen TB, Larsen K, Bjergelund L, Stilling M. Trapeziometacarpal joint implants can be evaluated by roentgen stereophotogrammetric analysis. J Hand Surg Eur Vol 2010; 35:480-5. [PMID: 20181771 DOI: 10.1177/1753193409355627] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Both marker-based roentgen stereophotogrammetric analysis (RSA) and model-based RSA have been helpful evaluation tools in hip and knee arthroplasty. The purpose of this study was to test both model-based and marker-based RSA in the evaluation of total joint prostheses of the trapeziometacarpal joint. In a phantom study, the precision of marker-based RSA was tested with a cemented polyethylene cup and compared with the precision of model-based RSA in an uncemented Elektra screw cup. The precision of model-based RSA of the metacarpal stem was tested using an uncemented Elektra metacarpal stem. In a clinical study 11 patients had double stereo radiographs followed by RSA analysis. The precision of translation in both marker-based and model-based RSA was sufficient for clinical use, but rotation cannot be estimated with sufficient precision.
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Affiliation(s)
- T B Hansen
- Department of Orthopaedics, Section of Hand Surgery, Regional Hospital Holstebro, Holstebro, Denmark.
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Walker PS, Yildirim G, Arno S, Heller Y. Future directions in knee replacement. Proc Inst Mech Eng H 2010; 224:393-414. [PMID: 20408486 DOI: 10.1243/09544119jeim655] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The use of artificial joints for the treatment of osteoarthritis is expected to expand considerably over the next decade. While newer technologies can offer yet further improvements in total knee systems, implementation will be strongly affected by the need to satisfy apparently competing requirements. Patients expect quicker rehabilitation, improved performance, and lifelong durability; on the other hand, economic constraints require a reduction in cost for each procedure, as well as early intervention and preventative measures, while there is increased pressure from health care systems to use evidence-based medicine as the standard of choice for implants and techniques. The success of a knee replacement depends on the design itself, the surgical technique, the rehabilitation, and, not least, the patient. The major goal of the implant design can be redefined as a restoration of normal knee mechanics, whether by maximum preservation of tissues, or by guiding surfaces that replace their function. Surgical technique needs to be less invasive but achieve optimal patient-specific alignment and soft tissue balancing. Rehabilitation procedures must achieve the expectations of realistic patients. Testing and evaluation methods need to be upgraded for enhanced predictability. This paper discusses current trends and future possibilities to address this expansive scope of design criteria.
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Affiliation(s)
- P S Walker
- Laboratory for Minimally-Invasive Surgery, Department of Orthopaedic Surgery, NYU Hospital for Joint Diseases, New York, NY 10010, USA.
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