96 results on '"Luyckx T"'
Search Results
2. Clinical outcomes in TKA are enhanced by both robotic assistance and patient specific alignment: a comparative trial in 120 patients
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Winnock de Grave, Philip, Kellens, J., Tampere, T., Vermue, H., Luyckx, T., and Claeys, K.
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- 2023
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3. The shape and orientation of the trochlea run more parallel to the posterior condylar line than generally believed
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Vercruysse, C., Vandenneucker, H., Bellemans, J., Scheys, L., and Luyckx, T.
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- 2018
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4. Bicruciate retaining total knee arthroplasty: current state and future promise
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COOLS, A.-S., primary, LUYCKX, T, additional, VICTOR, J, additional, and ARNOUT, N, additional
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- 2023
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5. Predictors of outcome after manipulation under anaesthesia in patients with a stiff total knee arthroplasty
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Vanlommel, L., Luyckx, T., Vercruysse, G., Bellemans, J., and Vandenneucker, H.
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- 2016
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6. Clinical outcomes in TKA are enhanced by both robotic assistance and patient specific alignment: a comparative trial in 120 patients
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Winnock de Grave, Philip, primary, Kellens, J., additional, Tampere, T., additional, Vermue, H., additional, Luyckx, T., additional, and Claeys, K., additional
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- 2022
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7. Should we aim at undercorrection when doing a total knee arthroplasty?
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Luyckx, T., Vanhoorebeeck, F., and Bellemans, J.
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- 2015
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8. The adductor ratio: a new tool for joint line reconstruction in revision TKA
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Luyckx, T., Beckers, L., Colyn, W., Vandenneucker, H., and Bellemans, J.
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- 2014
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9. How to improve femoral component rotational alignment in computer-assisted TKA
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Zambianchi, F., Luyckx, T., Victor, J., Digennaro, V., Giorgini, A., and Catani, F.
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- 2014
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10. Coronal alignment is a predictor of the rotational geometry of the distal femur in the osteo-arthritic knee
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Luyckx, T., Zambianchi, F., Catani, F., Bellemans, J., and Victor, J.
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- 2013
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11. Does hamstrings strength determine trunk control after total knee arthroplasty?
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Van Criekinge, T., primary, De Grave, P. Winnock, additional, Luyckx, T., additional, and Claeys, K., additional
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- 2021
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12. Is adapted measured resection superior to gap-balancing in determining femoral component rotation in total knee replacement?
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Luyckx, T., Peeters, T., Vandenneucker, H., Victor, J., and Bellemans, J.
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- 2012
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13. Anteroposterior positioning of the tibial component and its effect on the mechanics of patellofemoral contact
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Didden, K., Luyckx, T., Bellemans, J., Labey, L., Innocenti, B., and Vandenneucker, H.
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- 2010
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14. Is there a biomechanical explanation for anterior knee pain in patients with patella alta?: INFLUENCE OF PATELLAR HEIGHT ON PATELLOFEMORAL CONTACT FORCE, CONTACT AREA AND CONTACT PRESSURE
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Luyckx, T., Didden, K., Vandenneucker, H., Labey, L., Innocenti, B., and Bellemans, J.
- Published
- 2009
15. The shape and orientation of the trochlea run more parallel to the posterior condylar line than generally believed
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Vercruysse, C., primary, Vandenneucker, H., additional, Bellemans, J., additional, Scheys, L., additional, and Luyckx, T., additional
- Published
- 2017
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16. Predictors of outcome after manipulation under anaesthesia in patients with a stiff total knee arthroplasty.
- Author
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Vanlommel, L., Luyckx, T., Vercruysse, G., Bellemans, J., and Vandenneucker, H.
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TOTAL knee replacement ,RANGE of motion of joints ,ANESTHESIA ,ARTIFICIAL knees ,RANK correlation (Statistics) ,KNEE physiology ,KNEE surgery ,TREATMENT of surgical complications ,MANIPULATION therapy ,EPIDURAL anesthesia ,PROSTHETICS ,TIME ,RETROSPECTIVE studies ,GENERAL anesthesia - Abstract
Purpose: Flexion in a stiff total knee arthroplasty (TKA) can be improved by manipulation under anaesthesia (MUA). Although this intervention usually results in an improvement in range of motion, the expected result is not always achieved. The purpose of this study is to determine which factors affect range of motion after manipulation in patients with a stiff total knee.Methods: After exclusion (n = 22), the data of 158 patients (138 knees) with a stiff knee after TKA who received a manipulation under anaesthesia between 2004 and 2014 were retrospectively analysed. Pre-, peri- and post-operative variables were identified and examined for their influence on flexion after the manipulation using Kruskal-Wallis and Mann-Whitney U tests and Spearman correlations.Results: After MUA, a mean improvement in flexion of 30.3° was observed at the final follow-up. Preoperative TKA flexion, design of TKA and interval between TKA procedure and MUA were positive associated with an increase in flexion after MUA. MUA performed 12 weeks or more after TKA procedure deteriorated the outcome.Conclusions: Three factors, pre-TKA flexion type of prosthesis and interval between TKA procedure and manipulation under anaesthesia, were found to have impact on flexion after TKA and MUA were identified. Results are expected to be inferior in patients with low flexion before TKA procedure or with a long interval (>12 weeks) between the TKA procedure and the manipulation under anaesthesia.Level Of Evidence: IV. [ABSTRACT FROM AUTHOR]- Published
- 2017
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17. Should we aim at undercorrection when doing a total knee arthroplasty?
- Author
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Luyckx, T., primary, Vanhoorebeeck, F., additional, and Bellemans, J., additional
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- 2014
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18. Anteroposterior positioning of the tibial component and its effect on the mechanics of patellofemoral contact.
- Author
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Didden, K, Luyckx, T, Bellemans, J., Labey, Luc, Innocenti, Bernardo, Vandenneucker, H, Didden, K, Luyckx, T, Bellemans, J., Labey, Luc, Innocenti, Bernardo, and Vandenneucker, H
- Abstract
The biomechanics of the patellofemoral joint can become disturbed during total knee replacement by alterations induced by the position and shape of the different prosthetic components. The role of the patella and femoral trochlea has been well studied. We have examined the effect of anterior or posterior positioning of the tibial component on the mechanisms of patellofemoral contact in total knee replacement. The hypothesis was that placing the tibial component more posteriorly would reduce patellofemoral contact stress while providing a more efficient lever arm during extension of the knee. We studied five different positions of the tibial component using a six degrees of freedom dynamic knee simulator system based on the Oxford rig, while simulating an active knee squat under physiological loading conditions. The patellofemoral contact force decreased at a mean of 2.2% for every millimetre of posterior translation of the tibial component. Anterior positions of the tibial component were associated with elevation of the patellofemoral joint pressure, which was particularly marked in flexion > 90°. From our results we believe that more posterior positioning of the tibial component in total knee replacement would be beneficial to the patellofemoral joint., Journal Article, info:eu-repo/semantics/published
- Published
- 2010
19. Is there a biomechanical explanation for anterior knee pain in patients with patella alta? influence of patellar height on patellofemoral contact force, contact area and contact pressure.
- Author
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Luyckx, T, Didden, K, Vandenneucker, H, Labey, Luc, Innocenti, Bernardo, Bellemans, J., Luyckx, T, Didden, K, Vandenneucker, H, Labey, Luc, Innocenti, Bernardo, and Bellemans, J.
- Abstract
The purpose of this study was to test the hypothesis that patella alta leads to a less favourable situation in terms of patellofemoral contact force, contact area and contact pressure than the normal patellar position, and thereby gives rise to anterior knee pain. A dynamic knee simulator system based on the Oxford rig and allowing six degrees of freedom was adapted in order to simulate and record the dynamic loads during a knee squat from 30 degrees to 120 degrees flexion under physiological conditions. Five different configurations were studied, with variable predetermined patellar heights. The patellofemoral contact force increased with increasing knee flexion until contact occurred between the quadriceps tendon and the femoral trochlea, inducing load sharing. Patella alta caused a delay of this contact until deeper flexion. As a consequence, the maximal patellofemoral contact force and contact pressure increased significantly with increasing patellar height (p < 0.01). Patella alta was associated with the highest maximal patellofemoral contact force and contact pressure. When averaged across all flexion angles, a normal patellar position was associated with the lowest contact pressures. Our results indicate that there is a biomechanical reason for anterior knee pain in patients with patella alta., Journal Article, info:eu-repo/semantics/published
- Published
- 2009
20. Coronal alignment is a predictor of the rotational geometry of the distal femur in the osteo-arthritic knee
- Author
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Luyckx, T., primary, Zambianchi, F., additional, Catani, F., additional, Bellemans, J., additional, and Victor, J., additional
- Published
- 2012
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21. Kinematic alignment adequately restores trochlear anatomy, patellar kinematics and kinetics in total knee arthroplasty: A systematic review.
- Author
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Ollivier B, Luyckx T, Stragier B, and Vandenneucker H
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- Humans, Biomechanical Phenomena, Patella surgery, Patella anatomy & histology, Femur surgery, Femur anatomy & histology, Postoperative Complications prevention & control, Postoperative Complications etiology, Kinetics, Arthroplasty, Replacement, Knee methods, Patellofemoral Joint surgery, Patellofemoral Joint physiology
- Abstract
Purpose: Patellofemoral pain, maltracking and instability remain common and challenging complications after total knee arthroplasty. Controversy exists regarding the effect of kinematic alignment on the patellofemoral joint, as it generally leads to more femoral component valgus and internal rotation compared to mechanical alignment. The aim of this systematic review is to thoroughly examine the influence of kinematic alignment on the third space., Methods: A systematic search of the Pubmed, Cochrane and Web of Science databases was performed to screen for relevant articles published before 7 April 2024. This led to the final inclusion of 42 articles: 2 cadaveric, 9 radiographic, 12 computer simulation and 19 clinical studies. The risk of bias was evaluated with the risk of bias in non-randomised studies - of interventions tool as the lowest level of evidence of the included clinical studies was IV. The effects of kinematic alignment on patellar kinematics and kinetics, trochlear anatomy reconstruction and patellofemoral complication rate were investigated., Results: Kinematic alignment closely restores native patellar kinematics and kinetics, better reproduces native trochlear anatomy than mechanical alignment and leads to a 0%-11.4% incidence of patellofemoral complications. A more valgus joint line of the distal femur can cause lateral trochlear undercoverage and a trochlear angle orientation medial to the quadriceps vector when applying kinematic alignment, both of which can be solved by using an adjusted design with a 20.5° valgus trochlea., Conclusion: Kinematic alignment appears to be a safe strategy for the patellofemoral joint in most knees, provided that certain precautions are taken to minimize the risk of complications., Level of Evidence: Level IV clinical studies, in vitro research., (© 2024 European Society of Sports Traumatology, Knee Surgery and Arthroscopy.)
- Published
- 2025
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22. Effect of design and surgical parameters variations in mobile-bearing versus fixed-bearing unicompartmental knee arthroplasty: A finite element analysis.
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Luyckx T, Bori E, Saldari R, Fiore S, Altamore V, and Innocenti B
- Abstract
Purpose: Unicompartmental knee arthroplasty (UKAs) are available in the market as fixed- and mobile-bearing (FB and MB) and can be characterised by a different set of design parameters in terms of geometries, materials and surgical approaches, with overall good clinical outcomes. However, clear biomechanical evidence concerning the consequences of variations of these features on knee biomechanics is still lacking; therefore, the present study aims to perform a sensitivity analysis to see which outcomes are affected by these variations., Methods: For both MB-UKA and FB-UKA, five design and surgical parameters were defined (bearing insert thickness, tibial component material, implant components friction coefficient, antero-posterior slope angle and level of tibial bone resection). Two control models were defined based on standard configurations for both implants. Finite element analysis was chosen to perform this study, and different parameter combinations (216 models in total) were implemented and tested at both 0° and 90° of flexion, using a previously validated finite element knee model. The results were then evaluated in terms of bone and polyethylene Von Mises stress and tibio-femoral contact area., Results: Bearing thickness, tibial bone cut and slope angle were found to be the most sensitive parameters for both types of UKAs. Specifically, changes in these parameters in the FB-UKA appeared to induce more significant variations in the polyethylene insert (both in terms of polyethylene stress and contact area), while in the MB-UKA, these changes influenced bone stress distribution more., Conclusions: Surgical parameters returned to have a more significant influence than material and friction variations; furthermore, the outcomes most affected by parameter variations were the insert-related ones for FB-UKA while for the MB-UKA were the ones regarding tibial bone stresses., Level of Evidence: Not Applicable., Competing Interests: The authors have no conflicts of interest to declare., (© 2024 The Author(s). Journal of Experimental Orthopaedics published by John Wiley & Sons Ltd on behalf of European Society of Sports Traumatology, Knee Surgery and Arthroscopy.)
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- 2024
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23. Strong Correlation Between Standing Long-Leg Radiographs and CT Scans in Measuring Coronal Knee Alignment.
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Fontalis A, Luyckx T, Vanspauwen T, Moreels R, Mancino F, Raj RD, Winnock de Grave P, Plastow R, Putzeys P, and Haddad FS
- Abstract
Background: The objective of this study was to evaluate the correlation in measurements of the lower-limb coronal alignment between long-leg radiographs (LLRs) and computed tomography (CT) scanograms that were made during preoperative planning for robotic-arm-assisted knee arthroplasty. On the basis of published evidence demonstrating a good correlation between these imaging modalities in measuring the lower-limb mechanical axis, we hypothesized that there would be no significant differences between the 2 in the present study., Methods: This multicenter cohort study across 3 tertiary centers included 300 patients undergoing primary robotic-arm-assisted total knee arthroplasty (TKA) or unicompartmental knee arthroplasty (UKA) for whom LLRs and CT scanograms were available preoperatively. The study involved measuring the medial proximal tibial angle (MPTA), lateral distal femoral angle (LDFA), hip-knee-ankle angle (HKA), joint line obliquity (JLO), joint-line convergence angle (JLCA), and arithmetic HKA (aHKA). The aHKA represents a method for estimating constitutional alignment using angles that are unaffected by joint-space narrowing., Results: Strong correlations (p < 0.001) between the imaging modalities were found for the HKA (correlation coefficient, 0.912), aHKA (0.883), MPTA (0.820), LDFA (0.871), and JLO (0.778). A weaker correlation was observed for the JLCA in valgus knees as compared with varus knees (Spearman coefficients, 0.412 and 0.518, respectively). Regression models demonstrated that the degree of agreement was associated with the preoperative intra-articular deformity and the positioning of the lower limb during the CT scan (i.e., the lower-limb rotational angle). An initial JLCA within ±5° was associated with higher agreement., Conclusions: We observed a strong correlation between LLRs and CT scanograms that were made during the preoperative planning stage of robotic-arm-assisted knee arthroplasty, implying that CT scanograms can reliably be utilized to estimate the coronal alignment of the knee, potentially replacing the need for LLRs. Nevertheless, to attain a higher degree of agreement, it is crucial to ensure appropriate radiographic positioning of the lower limb. Additionally, surgeons must remain vigilant regarding potential discrepancies in cases involving substantial deformities., Level of Evidence: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence., Competing Interests: Disclosure: This work was supported by a scholarship from the Onassis Foundation (F ZR 065-1/2021-2022). The Article Processing Charge for open access publication was funded by University College London. The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJS/I7)., (Copyright © 2024 The Authors. Published by The Journal of Bone and Joint Surgery, Incorporated. All rights reserved.)
- Published
- 2024
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24. Widening of tibial resection boundaries increases the rate of femoral component valgus and internal rotation in functionally aligned TKA.
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Ollivier B, Wakelin E, Plaskos C, Vandenneucker H, and Luyckx T
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- Humans, Tibia surgery, Knee Joint surgery, Femur surgery, Retrospective Studies, Arthroplasty, Replacement, Knee methods, Knee Prosthesis, Osteoarthritis, Knee surgery
- Abstract
Purpose: The purpose of this study was to investigate the influence of increasing the tibial boundaries in functional alignment on femoral component orientation in total knee arthroplasty (TKA)., Methods: A retrospective review of a database of robotic-assisted TKAs using a digital joint tensioning device was performed (BalanceBot®; Corin). A total of 692 TKAs with correctable deformity were included. Functional alignment with a tibia-first balancing technique was simulated by performing an anatomic tibial resection to recreate the native medial proximal tibial angle within certain boundaries (A, 87-90°; B, 86-90°; C, 84-92°), while accounting for wear. After balancing the knee, the resulting amount of femoral component outliers in the coronal and axial plane was calculated for each group and correlated to the coronal plane alignment of the knee (CPAK) classification., Results: The proportion of knees with high femoral component varus (>96°) or valgus (<87°) alignment increased from 24.5% (n = 170) in group A to 26.5% (n = 183) in group B and 34.2% (n = 237) in group C (p < 0.05). Similarly, more knees with high femoral component external rotation (>6°) or internal rotation (>3°) were identified in group C (33.4%, n = 231) than in group B (23.7%, n = 164) and A (18.4%, n = 127) (p < 0.05). There was a statistically significant (p < 0.01) overall increase in knees with both femoral component valgus <87° and internal rotation >3° from group A (4.0%, n = 28) to B (7.7%, n = 53) and C (15.8%, n = 109), with CPAK type I and II showing a 12.9- and 2.9-fold increase, respectively., Conclusion: Extending the tibial boundaries when using functional alignment with a tibia-first balancing technique in TKA leads to a statistically significant higher percentage of knees with a valgus lateral distal femoral angle < 87° and >3° internal rotation of the femoral component, especially in CPAK type I and II., Level of Evidence: Level IV., (© 2024 European Society of Sports Traumatology, Knee Surgery and Arthroscopy.)
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- 2024
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25. A robotic-assisted simulation of kinematic alignment in TKA leads to excessive valgus and internal rotation in valgus knees.
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Ollivier B, Vandenneucker H, Vermue H, and Luyckx T
- Abstract
Purpose: Strategies to further improve patient satisfaction after total knee arthroplasty include the introduction of new alignment philosophies and more precise instruments such as navigation and robotics. The aim of this study was to investigate the effect of a combination of image-based robotic assistance and the use of modern alignment strategies on the resulting joint line obliquity as well as femoral component rotation and to compare this between varus, neutral and valgus knees., Methods: This retrospective study included 200 patients who received a robotic-assisted total knee arthroplasty (MAKO
® , Stryker) using functional alignment between 2018 and 2020. The patients were divided into a varus (103 patients), neutral (57 patients) and valgus (40 patients) group. The intraoperatively recorded bone cuts and resulting joint line obliquity were identified and compared to values obtained with a robotic computer simulation of kinematic alignment., Results: The mean femoral coronal alignment of the varus, neutral and valgus group, respectively, equalled 0.5° (± 1.1°), 1.1° (± 0.8°) and 1.6° (± 0.7°) of valgus with functional alignment and 2.1° (± 2.1°), 4.1° (± 1.7°) and 6.2° (± 1.7°) of valgus with kinematic alignment. The mean femoral axial alignment of the valgus group resulted in 0.8° (± 2.0°) of internal rotation with functional alignment and 3.9° (± 2.8°) of internal rotation with kinematic alignment. Overall, 186 knees (93%) could be balanced while respecting certain safe zones by using functional alignment as opposed to 54 knees (27% and none in the valgus group) when applying kinematic alignment. Kinematic alignment led to a combination of femoral component valgus and internal rotation of more than 3° in 22 valgus knees (55%), 10 neutral knees (18%) and 3 varus knees (3%) compared to none in each group when applying functional alignment with safe zones., Conclusions: Robotic-assisted kinematic alignment leads to a combination of excessive valgus and internal rotation of the femoral component in valgus and to a lesser extent also in neutral knees when compared with functional alignment., Level of Evidence: IV., (© 2023. The Author(s) under exclusive licence to European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA).)- Published
- 2023
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26. Restoration of the native tibial joint line obliquity in total knee arthroplasty with inverse kinematic alignment does not increase knee adduction moments.
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Winnock de Grave P, Van Criekinge T, Luyckx T, Moreels R, Gunst P, and Claeys K
- Abstract
Purpose: Patient-specific alignment in total knee arthroplasty (TKA) has shown promising patient-reported outcome measures; however, the clinical and biomechanical effects of restoring the native knee anatomy remain debated. The purpose of this study was to compare the gait pattern between a mechanically aligned TKA cohort (adjusted mechanical alignment-aMA) and a patient-specific alignment TKA cohort (inverse kinematic alignment-iKA)., Methods: At two years postoperatively, the aMA and iKA groups, each with 15 patients, were analyzed in a retrospective case-control study. All patients underwent TKA with robotic assistance (Mako, Stryker) through an identical perioperative protocol. The patients' demographics were identical. The control group comprised 15 healthy participants matched for age and gender. Gait analysis was performed with a 3D motion capture system (VICON). Data collection was conducted by a blinded investigator. The primary outcomes were knee flexion during walking, knee adduction moment during walking and spatiotemporal parameters (STPs). The secondary outcomes were the Oxford Knee Score (OKS) and Forgotten Joint Score (FJS)., Results: During walking, the maximum knee flexion did not differ between the iKA group (53.0°) and the control group (55.1°), whereas the aMA group showed lower amplitudes of sagittal motion (47.4°). In addition, the native limb alignment in the iKA group was better restored, and although more in varus, the knee adduction moments in the iKA group were not increased (225 N mm/kg) compared to aMA group (276 N mm/kg). No significant differences in STPs were observed between patients receiving iKA and healthy controls. Six of 7 STPs differed significantly between patients receiving aMA and healthy controls. The OKS was significantly better in patients receiving iKA than aMA: 45.4 vs. 40.9; p = 0.05. The FJS was significantly better in patients receiving iKA than aMA: 84.8 vs. 55.5; p = 0.002., Conclusion: At two years postoperatively, the gait pattern showed greater resemblance to that in healthy controls in patients receiving iKA rather than aMA. The restoration of the native coronal limb alignment does not lead to increased knee adduction moments due to the restoration of the native tibial joint line obliquity., Level of Evidence: Level III., (© 2023. The Author(s) under exclusive licence to European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA).)
- Published
- 2023
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27. Inverse kinematic alignment accommodates native coronal knee alignment better in comparison to adjusted mechanical alignment and restricted kinematic alignment.
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Winnock de Grave P, Luyckx T, Van Criekinge T, Müller JH, Ollivier B, Van Eecke E, LiArno S, Faizan A, and Claeys K
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- Humans, Biomechanical Phenomena, Knee Joint diagnostic imaging, Knee Joint surgery, Lower Extremity, Femur diagnostic imaging, Femur surgery, Retrospective Studies, Tibia surgery, Arthroplasty, Replacement, Knee methods, Osteoarthritis, Knee diagnostic imaging, Osteoarthritis, Knee surgery
- Abstract
Purpose: The purpose was to determine the proportion of native non-arthritic knees that fit within the target zones of adjusted mechanical alignment (aMA), restricted kinematic alignment (rKA), and inverse kinematic alignment (iKA), and to estimate adjustments in native coronal alignment to bring outlier knees within the respective target zones. The hypothesis was that the target zone of iKA, compared to the target zones of aMA and rKA, accommodates a higher proportion of native non-arthritic knees., Methods: The study used measurements obtained from a computed tomography (CT) scan database (SOMA, Stryker) of 972 healthy knees (Caucasian, 586; Asian, 386). Hip knee ankle (HKA) angle, medial proximal tibial angle (MPTA) and lateral distal femoral angle (LDFA) were used to estimate the proportions of knees within the patient-specific alignment target zones; and to estimate theoretical adjustments of MPTA, LDFA and soft tissue balance (HKA) to bring outlier knees within target zones. Theoretical adjustments to bring outlier knees within the alignment target zones of aMA, rKA and iKA were calculated by subtracting the native coronal alignment angles (MPTA
native , LDFAnative and HKAnative ) from angles on the nearest target zone border (MPTAtarget , LDFAtarget and HKAtarget )., Results: Patients were aged 59.8 ± 15.8 years with a BMI of 25.0 ± 4.4 kg/m2 . The HKA angles were between 168° and 186°, MPTA between 78° and 98° and LDFA between 79° and 93°. Of the 972 knees, 81 (8%) were in the aMA target zone, 530 (55%) were in the rKA target zone, and 721 (74%) were in the iKA target zone. Adjustments of MPTA, LDFA and HKA angle to bring outlier knees within the target zones, were, respectively, 90, 91 and 28% for aMA, 45, 28 and 25% for rKA, and 25, 23 and 7% for iKA., Conclusions: There is considerable variability in native knee coronal alignment that corresponds to different proportions of the restricted patient-specific alignment target zones for TKA. Although extension of the MPTA and LDFA target zones with rKA accommodate native knee alignment better than aMA, up to 25% would require adjustment of native HKA angle. By also extending the HKA angle target zone into varus, iKA accommodates a greater proportion (93%) of native limb alignment., Level of Evidence: IV., (© 2023. The Author(s) under exclusive licence to European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA).)- Published
- 2023
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28. The evolution of robotic systems for total knee arthroplasty, each system must be assessed for its own value: a systematic review of clinical evidence and meta-analysis.
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Vermue H, Batailler C, Monk P, Haddad F, Luyckx T, and Lustig S
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- Humans, Outcome Assessment, Health Care, Operative Time, Knee Joint surgery, Arthroplasty, Replacement, Knee methods, Robotic Surgical Procedures methods, Osteoarthritis, Knee surgery
- Abstract
Introduction: Robotic systems have been introduced to improve the precision of total knee arthroplasty. However, different robotic systems are available, each with unique features used to plan and execute the surgery. As such, due to this diversity, the clinical evaluation of each robotic platform should be separated., Methods: An extensive literature search of PubMed, Medline, Embase and Web of Science was conducted with subsequent meta-analysis. Randomised controlled trials, comparative studies, and cohort studies were included regarding robot-assisted total knee arthroplasty. Evaluated outcomes included clinical results, surgical precision, ligament balance, surgical time, learning curve, complications and revision rates. These were split up based on the robot-specific brand: ROBODOC (T-SOLUTION ONE), OMNIBOT, MAKO, NAVIO (CORI) and ROSA., Results: With a follow-up of more than 10 years, no improved clinical outcomes have been noted with the ROBODOC system compared to the conventional technique. If available, other platforms only present short-term clinical outcomes. Radiological outcomes are published for most robotic setups, demonstrating improved surgical precision compared to the conventional technique. Gap balance assessment is performed differently between all systems, leading to heterogeneous outcomes regarding its relationship on clinical outcomes. There is a similar learning curve based on operative time for all robotic platforms. In most studies, robot assistance requires longer operative time compared to the conventional technique. Complications and revision rates are published for ROBODOC and MAKO, without clear differences to conventional total knee arthroplasty., Conclusion: The main finding of this systematic review is that the current evidence regarding each robotic system is diverse in quantity and quality. Each system has its own specificities and must be assessed for its own value. Regarding scientific literature, the generic term of robotic should be banned from the general conclusion., Level of Evidence: Systematic review level IV., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
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- 2023
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29. What are the perceived benefits and barriers to the use of robot-assisted total knee arthroplasty? A survey of members of the European Knee Society.
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Luyckx T, Monk AP, Müller JH, Saffarini M, Lustig S, Catani F, and Bonnin MP
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- Humans, Knee Joint surgery, Lower Extremity surgery, Surveys and Questionnaires, Arthroplasty, Replacement, Knee methods, Robotics methods
- Abstract
Purpose: Members of the European Knee Society (EKS) recently took part in an online questionnaire on robot-assisted TKA. The purpose of this study was to report and analyse the questionnaire results on the demographics of users versus non-users, the drivers for users of the technology, and the barriers or limitations that hinder the uptake of robot-assisted TKA., Methods: The questionnaire was composed of 16 questions covering surgeon demographics and drivers for or barriers to the use of robotics. Responses on four- or five-point Likert scales were trichotomised depending on the type of question ("not important" - "moderately important" - "important/very important" or "fully disagree/disagree" - "neutral" - "agree/fully agree"). Consensus on a statement was defined as at least 75% agreement., Results: There was a 67% response rate. Forty-five surgeons performed conventional TKA, of which 78% aimed for systematic alignment, while 22 performed robot-assisted TKA, of which 82% aimed for individualised alignment, and 16 performed technology-assisted TKA, of which 56% aimed for systematic alignment. Respondents agreed that robotics significantly impact accuracy of bone cuts (51/62, 82%), intra-operative feedback on ligament balancing (56/62, 90%) as well as bone cut orientation and implant positioning (57/ 62, 92%), and assistance to customise alignment (56/62, 90%). Respondents agreed that associated costs (14/18, 78%) are an important aspect for not using or to stop using robotics., Conclusion: The majority of respondents still perform conventional TKA (54%), while only a small portion perform robot-assisted TKA (27%) or other technology-assisted TKA (19%). Most robot users aim for individualised lower limb alignment, whereas most other surgeons aimed for systematic lower limb alignment. There is consensus that robotic assistance has a positive impact on accuracy of bone cuts and alignment, but no consensus on its impact on other peri- or post-operative outcomes. Finally, the associated cost of robot-assisted TKA remains the main barrier to its uptake., Level of Evidence: V., (© 2022. The Author(s) under exclusive licence to SICOT aisbl.)
- Published
- 2023
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30. Inverse Kinematic Alignment for Total Knee Arthroplasty.
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Winnock de Grave P, Kellens J, Luyckx T, Tampere T, Lacaze F, and Claeys K
- Subjects
- Biomechanical Phenomena, Humans, Knee Joint diagnostic imaging, Knee Joint surgery, Tibia surgery, Arthroplasty, Replacement, Knee methods, Knee Prosthesis, Osteoarthritis, Knee surgery
- Abstract
Patient specific alignment might improve clinical outcomes in total knee arthroplasty (TKA). Different alignment concepts are described, each providing specific features with theoretical benefits or possible disadvantages. Inverse kinematic alignment (iKA) is a new patient specific alignment concept with excellent reported clinical outcome and patient satisfaction at short-term follow-up. iKA is a tibia-first, gap balancing technique restoring the native tibial joint line obliquity (JLO). In each patient, within boundaries, equal medial and lateral tibial resections are performed, compensating for cartilage and bone loss. We describe the surgical technique of iKA using a robotic assisted system (Mako, Stryker, Kalamazoo, USA). A case series of 100 consecutive iKA cases is assessed and the bony resections and resection angles are reported. Both in the coronal plane and axial plane, iKA might offer advantages over existing alignment strategies, possibly providing optimal clinical outcome and durable long-term survival, regardless of the alignment is varus, neutral or valgus., (Copyright © 2022 The Author(s). Published by Elsevier Masson SAS.. All rights reserved.)
- Published
- 2022
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31. Equal bony resection of distal and posterior femur will lead to flexion/extension gap inequality in robot-assisted cruciate-retaining TKA.
- Author
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Vermue H, Winnock de Grave P, Ryckaert A, and Luyckx T
- Subjects
- Biomechanical Phenomena, Femur surgery, Humans, Knee Joint surgery, Range of Motion, Articular, Retrospective Studies, Arthroplasty, Replacement, Knee methods, Osteoarthritis, Knee surgery, Robotics
- Abstract
Purpose: Joint imbalance has become one of the main reasons for early revision after total knee arthroplasty (TKA) and it is directly related to the surgical technique. Therefore, a better understanding of how much bone has to be removed to obtain a balanced flexion/extension gap could improve current practice. The primary objective of this study was to analyse the amount of bone that needed to be removed from the distal and posterior femoral joint surfaces to obtain an equal flexion/extension gap in robot-assisted TKA. The second objective of this study was to evaluate whether the size of the knee joint influenced the amount of bony resection needed to achieve an equal flexion/extension gap in robot-assisted TKA., Methods: A retrospective analysis was performed on all patients receiving a robot-assisted TKA (Cruciate Retaining (n = 268)) by six surgeons from April 2018 to September 2019. The robot was used consecutively when available in all patients receiving Cruciate Retaining TKA. Gap assessment, bony resections, femoral implant size and hip-knee-ankle angle were evaluated with the robot. Femoral implant size was categorized into small (size 1-2), medium (size 3-5) and large (size 6-8)., Results: The difference between the posterior and distal resection needed to obtain equal flexion and extension gap was on average 2.0 mm (SD 1.6) and 1.5 mm (SD 2.2) for the medial and lateral compartment, respectively. The discrepancy was smaller in the large implant group compared to the small implant group (p < .05 medial and lateral) and medium implant group (p < .05 medial). Varus knees required a larger differential resection compared to neutral and valgus knees (only laterally) (medial compartment: p < .05 (varus-neutral), p = .051 (varus-valgus); lateral compartment: p < .05 (varus-neutral and varus-valgus)., Conclusion: Removing an equal amount of bone from the distal and posterior femur will lead to flexion/extension gap imbalance in TKA. It was required to remove 1.5-2 mm more bone from the posterior femur compared to the distal femur to equalize flexion and extension gap. This effect was size dependent: in larger knees, the discrepancy between the distal and posterior resections was smaller., Level of Evidence: IV., (© 2021. European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA).)
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- 2022
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32. Bioavailability and Health Impact of Ingested Amyloid-like Protein Fibrils and their Link with Inflammatory Status: A Need for More Research?
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Luyckx T, Grootaert C, Monge-Morera M, Delcour JA, Rousseau F, Schymkowitz J, and Van Camp J
- Subjects
- Amyloid metabolism, Biological Availability, Humans, Amyloidogenic Proteins metabolism, Amyloidosis etiology, Amyloidosis metabolism
- Abstract
The use of amyloid-like protein fibrils (ALFs) in food formulations looks very promising in terms of improving techno-functional properties, but raises some concerns in terms of food safety, because of their structural resemblance to disease-related endogenous amyloids. This review focuses on the biological fate and potential health implications of ingested ALF structures in both healthy and predisposed individuals. A comprehensive overview of ALF gastrointestinal digestion, intestinal absorption, and systemic dissemination is provided, in addition to a thorough assessment of potential ALF cross-seeding of endogenous precursor proteins linked to (non)neurodegenerative amyloidosis. In general, this study concludes that the health impact of ALF consumption remains widely understudied and merits additional research efforts to determine the exact extent to which ALF ingestion may influence the general health status., (© 2022 Wiley-VCH GmbH.)
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- 2022
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33. Trunk control, motion and alignment after total knee arthroplasty: a systematic review and meta-analysis.
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Van Criekinge T, Winnock de Grave P, Luyckx T, and Claeys K
- Subjects
- Adult, Biomechanical Phenomena, Humans, Knee Joint, Quality of Life, Range of Motion, Articular, Arthroplasty, Replacement, Knee methods, Osteoarthritis, Knee surgery
- Abstract
Background: Trunk control improves mobility, balance and quality of life early after total knee arthroplasty (TKA) and is therefore considered an important parameter during the recovery process. However, little is known about trunk control, motion and alignment after TKA. Increasing our understanding aids in optimizing treatment strategies to enhance functional mobility after TKA., Research Question: Does trunk control, motion and alignment return to normal after TKA and is this related to functional mobility?, Methods: Five scientific databases were searched until July 2021. Eligibility criteria consisted of outcomes assessing trunk control and alignment in a population of adults undergoing TKA. Two reviewers independently screened studies and risk of bias was assessed by Mixed Methods Appraisal Tool (MMAT). Meta-analysis was performed for subgroups gait and alignment., Results: Of the 362 studies retrieved, 24 were included. Study designs were cohorts with mixed methods (pre-post treatment, case-control and case-case) and three randomized controlled trials. The mean MMAT score was 75%, corresponding to low bias. In total 1178 patients and 197 controls were included. Results showed that pre-operative trunk motion was characterized by increased amplitudes in all three planes and altered alignment which did not all return to normal after TKA. Frontal plane motion and alignment recovered faster than the sagittal and transversal plane. Although pelvic tilt improved after surgery, sagittal imbalance (anteriorly shifted trunk position) was still present., Significance: Recovery of trunk motion after TKA is time-, speed- and technique-dependent. The observed differences in trunk motion with the healthy controls persisted after TKA. This indicates that incorporating a full biomechanical chain approach, including trunk motion and gait-retraining exercises with a strong focus on postural alignment could improve functional mobility after TKA. Limited studies are available assessing trunk control and trunk motion during functional tasks besides walking which warrant further investigation., (Copyright © 2022 Elsevier B.V. All rights reserved.)
- Published
- 2022
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34. Higher satisfaction after total knee arthroplasty using restricted inverse kinematic alignment compared to adjusted mechanical alignment.
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Winnock de Grave P, Luyckx T, Claeys K, Tampere T, Kellens J, Müller J, and Gunst P
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- Biomechanical Phenomena, Humans, Knee Joint surgery, Personal Satisfaction, Treatment Outcome, Arthroplasty, Replacement, Knee methods, Knee Prosthesis, Osteoarthritis, Knee surgery
- Abstract
Purpose: Various alignment philosophies for total knee arthroplasty (TKA) have been described, all striving to achieve excellent long-term implant survival and good functional outcomes. In recent years, in search of higher functionality and patient satisfaction, a shift towards more tailored and patient-specific alignment is seen. The purpose of this study was to describe a restricted 'inverse kinematic alignment' (iKA) technique, and to compare clinical outcomes of patients that underwent robotic-assisted TKA performed by restricted iKA vs. adjusted mechanical alignment (aMA)., Methods: The authors reviewed the records of a consecutive series of patients that received robotic-assisted TKA with restricted iKA (n = 40) and with aMA (n = 40). Oxford Knee Score (OKS) and satisfaction on a visual analogue scale (VAS) were collected at a follow-up of 12 months. Clinical outcomes were assessed according to patient acceptable symptom state (PASS) thresholds, and uni- and multivariable linear regression analyses were performed to determine associations of OKS and satisfaction with six variables (age, sex, body mass index (BMI), preoperative hip-knee-ankle (HKA) angle, preoperative OKS, alignment technique)., Results: The restricted iKA and aMA techniques yielded comparable outcome scores (p = 0.069), with OKS, respectively, 44.6 ± 3.5 and 42.2 ± 6.3. VAS Satisfaction was better (p = 0.012) with restricted iKA (9.2 ± 0.8) compared to aMA (8.5 ± 1.3). The number of patients that achieved OKS and satisfaction PASS thresholds was significantly higher (p = 0.049 and p = 0.003, respectively) using restricted iKA (98% and 80%) compared to aMA (85% and 48%). Knees with preoperative varus deformity, achieved significantly (p = 0.025) better OKS using restricted iKA (45.4 ± 2.0) compared to aMA (41.4 ± 6.8). Multivariable analyses confirmed better OKS (β = 3.1; p = 0.007) and satisfaction (β = 0.73; p = 0.005) with restricted iKA., Conclusions: The results of this study suggest that restricted iKA and aMA grant comparable clinical outcomes at 12-month follow-up, though a greater proportion of knees operated by restricted iKA achieved the PASS thresholds for OKS and satisfaction. Notably. in knees with preoperative varus deformity, restricted iKA yielded significantly better OKS and satisfaction than aMA., Level of Evidence: Level III, comparative study., (© 2020. The Author(s).)
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- 2022
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35. Robot-assisted total knee arthroplasty is associated with a learning curve for surgical time but not for component alignment, limb alignment and gap balancing.
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Vermue H, Luyckx T, Winnock de Grave P, Ryckaert A, Cools AS, Himpe N, and Victor J
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- Humans, Knee Joint surgery, Learning Curve, Operative Time, Retrospective Studies, Arthroplasty, Replacement, Knee, Osteoarthritis, Knee surgery, Robotic Surgical Procedures, Robotics
- Abstract
Purpose: The application of robotics in the operating theatre for total knee arthroplasty (TKA) remains controversial. As with all new technology, the introduction of new systems is associated with a learning curve and potentially associated with extra complications. Therefore, the aim of this study is to identify and predict the learning curve of robot-assisted (RA) TKA., Methods: A RA TKA system (MAKO) was introduced in April 2018 in our service. A retrospective analysis was performed of all patients receiving a TKA with this system by six surgeons. Operative times, implant and limb alignment, intraoperative joint balance and robot-related complications were evaluated. Cumulative summation (CUSUM) analyses were used to assess learning curves for operative time, implant alignment and joint balance in RA TKA. Linear regression was performed to predict the learning curve of each surgeon., Results: RA TKA was associated with a learning curve of 11-43 cases for operative time (p < 0.001). This learning curve was significantly affected by the surgical profile (high vs. medium vs. low volume). A complete normalisation of operative times was seen in four out of five surgeons. The precision of implant positioning and gap balancing showed no learning curve. An average deviation of 0.2° (SD 1.4), 0.7° (SD 1.1), 1.2 (SD 2.1), 0.2° (SD 2.9) and 0.3 (SD 2.4) for the mLDFA, MPTA, HKA, PDFA and PPTA from the preoperative plan was observed. Limb alignment showed a mean deviation of 1.2° (SD 2.1) towards valgus postoperatively compared to the intraoperative plan. One tibial stress fracture was seen as a complication due to suboptimal positioning of the registration pins., Conclusion: RA TKA is associated with a learning curve for surgical time, which might be longer than reported in current literature and dependent on the profile of the surgeon. There is no learning curve for component alignment, limb alignment and gap balancing., Level of Evidence: IV., (© 2020. European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA).)
- Published
- 2022
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36. Biceps Femoris Compensates for Semitendinosus After Anterior Cruciate Ligament Reconstruction With a Hamstring Autograft: A Muscle Functional Magnetic Resonance Imaging Study in Male Soccer Players.
- Author
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Tampere T, Victor J, Luyckx T, Vermue H, Arnout N, Witvrouw E, and Schuermans J
- Subjects
- Autografts, Humans, Magnetic Resonance Imaging, Male, Anterior Cruciate Ligament Injuries surgery, Anterior Cruciate Ligament Reconstruction, Hamstring Muscles diagnostic imaging, Hamstring Tendons diagnostic imaging, Soccer
- Abstract
Background: Rates of reinjury, return to play (RTP) at the preinjury level, and hamstring strain injuries in male soccer players after anterior cruciate ligament reconstruction (ACLR) remain unsatisfactory, due to multifactorial causes. Recent insights on intramuscular hamstring coordination revealed the semitendinosus (ST) to be of crucial importance for hamstring functioning, especially during heavy eccentric hamstring loading. Scientific evidence on the consequences of ST tendon harvest for ACLR is scarce and inconsistent. This study intended to investigate the repercussions of ST harvest for ACLR on hamstring muscle function., Hypothesis: Harvest of the ST tendon for ACLR was expected to have a significant influence on hamstring muscle activation patterns during eccentric exercises, evaluated at RTP in a population of male soccer athletes., Study Design: Controlled laboratory study., Methods: A total of 30 male soccer players with a history of ACLR who were cleared for RTP and 30 healthy controls were allocated to this study during the 2018-2019 soccer season. The influence of ACLR on hamstring muscle activation patterns was assessed by comparing the change in T2 relaxation times [ΔT2 (%) = post - exercise - T 2 pre - exercise T 2 pre - exercise ] of the hamstring muscle tissue before and after an eccentric hamstring loading task between athletes with and without a recent history of ACLR through use of muscle functional magnetic resonance imaging, induced by an eccentric hamstring loading task between scans., Results: Significantly higher exercise-related activity was observed in the biceps femoris (BF) of athletes after ACLR compared with uninjured control athletes (13.92% vs 8.48%; P = .003), whereas the ST had significantly lower activity (19.97% vs 25.32%; P = .049). Significant differences were also established in a within-group comparison of the operated versus the contralateral leg in the ACLR group (operated vs nonoperated leg: 14.54% vs 11.63% for BF [ P = .000], 17.31% vs 22.37% for ST [ P = .000], and 15.64% vs 13.54% for semimembranosus [SM] [ P = .014]). Neither the muscle activity of SM and gracilis muscles nor total posterior thigh muscle activity (sum of exercise-related ΔT2 of the BF, ST, and SM muscles) presented any differences in individuals who had undergone ACLR with an ST tendon autograft compared with healthy controls., Conclusion: These findings indicate that ACLR with a ST tendon autograft might notably influence the function of the hamstring muscles and, in particular, their hierarchic dimensions under fatiguing loading circumstances, with increases in relative BF activity contribution and decreases in relative ST activity after ACLR. This between-group difference in hamstring muscle activation pattern suggests that the BF partly compensates for deficient ST function in eccentric loading. These alterations might have implications for athletic performance and injury risk and should probably be considered in rehabilitation and hamstring injury prevention after ACLR with a ST tendon autograft.
- Published
- 2021
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37. Reduced joint awareness after total knee arthroplasty with a cruciate retaining design.
- Author
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Thuysbaert G, Luyckx T, Ryckaert A, Gunst P, Noyez J, and Winnock De Grave P
- Subjects
- Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Retrospective Studies, Surveys and Questionnaires, Arthroplasty, Replacement, Knee methods, Awareness, Knee Prosthesis, Patient Satisfaction, Prosthesis Design, Quality of Life
- Abstract
A range of different total knee arthroplasty (TKA) designs have been developed, each specifically designed to relieve pain and restore knee function with the greatest possible patient satisfaction. The purpose of this study was to compare a posterior stabilized design and a cruciate-retaining design. We hypothesized that a cruciate-retaining design would have a higher Forgotten Joint Score (FJS) than a posterior stabilized design. Ninety-two patients were used in our analysis (46 patients in each group) involving TKA (Attune, Depuy-Synthes) between January 2014 and March 2015. We excluded patients with valgus alignment, post-traumatic arthritis, rheumatoid arthritis and major previous surgery on the knee. We compared the FJS, the Oxford Knee Score (OKS) and their ceiling effects. FJS was significantly higher in the fixed-bearing cruciate-retaining group (P=0.043). The mean (-SD) FJS for the cruciate-retaining group was 78,4-25.1 compared to 67.6-27.6 for the posterior stabilized group. No significant difference in OKS was detected. The total ceiling effect for FJS and OKS was 32.2% and 45.5%, respectively. In conclusion, patients with cruciate-retaining TKA showed a better FJS in comparison to posterior stabilized TKA. FJS has a higher discriminatory power compared to OKS.
- Published
- 2020
38. Medial Unicompartmental Knee Arthroplasty with a Fixed Bearing Implant.
- Author
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Winnock de Grave P, Luyckx T, Ryckaert A, Noyez J, Gunst P, and Van den Daelen L
- Abstract
Unicompartmental knee arthroplasty (UKA) is an alternative to total knee arthroplasty in isolated medial arthritis. UKA restores native tibial and femoral joint surfaces and corrects pre-disease limb alignment, by which natural knee biomechanics are restored, ensuring effective functional recovery. Proper patient selection and accurate surgical technique contribute to good functional outcome and long-term survival. The key steps of the procedure (as well as multiple tips and tricks) are demonstrated in the video article: (1) preoperative assessment and planning; (2) patient positioning and setup; (3) exposure; (4) instrument options and surgical technique; (5) distal femoral resection; (6) proximal tibial resection; (7) assessment of alignment and gaps; (8) finishing the femur-sizing, position, and posterior resection; (9) finishing the tibia-sizing and position; (10) trialing the implant; (11) implanting final components-cementing technique; (12) closure; and (13) rehabilitation. Following these surgical steps and principles will lead to excellent functional long-term results with a low revision rate and a minimum of complications., (Copyright © 2019 The Authors. Published by The Journal of Bone and Joint Surgery, Incorporated.)
- Published
- 2019
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39. Tunnel placement in ACL reconstruction surgery: smaller inter-tunnel angles and higher peak forces at the femoral tunnel using anteromedial portal femoral drilling-a 3D and finite element analysis.
- Author
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Tampere T, Devriendt W, Cromheecke M, Luyckx T, Verstraete M, and Victor J
- Subjects
- Adult, Anterior Cruciate Ligament surgery, Anterior Cruciate Ligament Reconstruction statistics & numerical data, Biomechanical Phenomena, Female, Finite Element Analysis, Humans, Male, Motion, Postoperative Period, Tibia surgery, Young Adult, Anterior Cruciate Ligament Reconstruction methods, Femur surgery, Knee Joint surgery
- Abstract
Purpose: Recent studies have emphasized the importance of anatomical ACL reconstruction to restore normal knee kinematics and stability. Aim of this study is to evaluate and compare the ability of the anteromedial (AM) and transtibial (TT) techniques for ACL reconstruction to achieve anatomical placement of the femoral and tibial tunnel within the native ACL footprint and to determine forces within the graft during functional motion. As the AM technique is nowadays the technique of choice, the hypothesis is that there are significant differences in tunnel features, reaction forces and/or moments within the graft when compared to the TT technique., Methods: Twenty ACL-deficient patients were allocated to reconstruction surgery with one of both techniques. Postoperatively, all patients underwent a computed tomography scan (CT) allowing 3D reconstruction to analyze tunnel geometry and tunnel placement within the native ACL footprint. A patient-specific finite element analysis (FEA) was conducted to determine reaction forces and moments within the graft during antero-posterior translation and pivot-shift motion., Results: With significantly shorter femoral tunnels (p < 0.001) and a smaller inter-tunnel angle (p < 0.001), the AM technique places tunnels with less variance, close to the anatomical centre of the ACL footprints when compared to the TT technique. Using the latter, tibial tunnels were more medialised (p = 0.007) with a higher position of the femoral tunnels (p = 0.02). FEA showed the occurrence of higher, but non-significant, reaction forces in the graft, especially on the femoral side and lower, however, statistically not significant, reaction moments using the AM technique., Conclusion: This study indicates important, technique-dependent differences in tunnel features with changes in reaction forces and moments within the graft., Level of Evidence: II.
- Published
- 2019
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40. Outcomes of a Fixed-Bearing, Medial, Cemented Unicondylar Knee Arthroplasty Design: Survival Analysis and Functional Score of 460 Cases.
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Winnock de Grave P, Barbier J, Luyckx T, Ryckaert A, Gunst P, and Van den Daelen L
- Subjects
- Aged, Disease Progression, Female, Humans, Kaplan-Meier Estimate, Male, Middle Aged, Osteonecrosis surgery, Pain surgery, Patella surgery, Postoperative Period, Prosthesis Design, Prosthesis Failure, Reoperation statistics & numerical data, Retrospective Studies, Survival Analysis, Synovitis etiology, Time Factors, Treatment Outcome, Arthroplasty, Replacement, Knee, Knee Joint surgery, Knee Prosthesis, Osteoarthritis, Knee surgery
- Abstract
Background: Unicompartmental knee arthroplasty (UKA) is an alternative to total knee arthroplasty in isolated medial osteoarthritis (OA). However, despite satisfactory reports on the clinical performance, UKA revision rates are still concerning. This retrospective study reports on the long-term survivorship, functional outcomes, and reasons for revision in fixed-bearing UKA implant., Methods: Between 2005 and 2013, 460 consecutive patients were treated with medial UKA in one center using a fixed-bearing UKA system. All patients were evaluated clinically and radiographically before surgery, and postoperatively at 6 weeks and 1 year. Between February and April 2016, all patients were reevaluated using the Oxford Knee Score., Results: Mean follow-up was 5.5 (range, 2-11) years. The mean Oxford Knee Score was 43.3 (7-48), with 94.6% patients showing excellent or good outcomes. Eleven revisions (2.4%) occurred. The survivorship was 97.2% (95% confidence interval, 96.2%-99.2%) and 94.2% (95% confidence interval, 86.8%-97.5%) at 5 and 10 years, respectively, with revision of any implant component for any reason as the end point. The causes for revision were infection (4 cases, 0.9%); lateral pain due to overload (2 cases, 0.4%); progression of OA in the lateral compartment (2 cases, 0.4%); patellar pain with patellar chondropathy (2 cases, 0.4%); and severe synovitis (1 cases, 0.2%). There were no reoperations or revisions for component loosening, instability, component wear, or periprosthetic fracture., Conclusion: A fixed-bearing UKA system is a good treatment option for medial end-stage OA. Satisfactory functional results were achieved with low incidence of complications and revisions., (Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.)
- Published
- 2018
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41. Raising the Joint Line in TKA is Associated With Mid-flexion Laxity: A Study in Cadaver Knees.
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Luyckx T, Vandenneucker H, Ing LS, Vereecke E, Ing AV, and Victor J
- Subjects
- Aged, Aged, 80 and over, Arthroplasty, Replacement, Knee instrumentation, Arthroplasty, Replacement, Knee methods, Biomechanical Phenomena, Cadaver, Female, Femur pathology, Femur physiopathology, Humans, Joint Instability physiopathology, Knee Joint pathology, Knee Joint physiopathology, Knee Prosthesis, Male, Medial Collateral Ligament, Knee pathology, Medial Collateral Ligament, Knee physiopathology, Medial Collateral Ligament, Knee surgery, Middle Aged, Models, Anatomic, Random Allocation, Range of Motion, Articular, Risk Assessment, Risk Factors, Arthroplasty, Replacement, Knee adverse effects, Femur surgery, Joint Instability etiology, Knee Joint surgery
- Abstract
Background: In a typical osteoarthritic knee with varus deformity, distal femoral resection based off the worn medial femoral condyle may result in an elevated joint line. In a setting of fixed flexion contracture, the surgeon may choose to resect additional distal femur to obtain extension, thus purposefully raising the joint line. However, the biomechanical effect of raising the joint line is not well recognized., Questions/purposes: (1) What is the effect of the level of the medial joint line (restored versus raised) on coronal plane stability of a TKA? (2) Does coronal alignment technique (mechanical axis versus kinematic technique) affect coronal plane stability of the knee? (3) Can the effect of medial joint-line elevation on coronal plane laxity be predicted by an analytical model?, Methods: A TKA prosthesis was implanted in 10 fresh frozen nonarthritic cadaveric knees with restoration of the medial joint line at its original level (TKA0). Coronal plane stability was measured at 0°, 30°, 60°, 90°, and 120° flexion using a navigation system while applying an instrumented 9.8-Nm varus and valgus force moment. The joint line then was raised in two steps by recutting the distal and posterior femur by an extra 2 mm (TKA2) and 4 mm (TKA4), downsizing the femoral component and, respectively, adding a 2- and a 4-mm thicker insert. This was done with meticulous protection of the ligaments to avoid damage. Second, a simplified two-dimensional analytical model of the superficial medial collateral ligament (MCL) length based on a single flexion-extension axis was developed. The effect of raising the joint line on the length of the superficial MCL was simulated., Results: Despite that at 0° (2.2° ± 1.5° versus 2.3° ± 1.1° versus 2.5° ± 1.1°; p = 0.85) and 90° (7.5° ± 1.9° versus 9.0° ± 3.1° versus 9.0° ± 3.5°; p = 0.66), there was no difference in coronal plane laxity between the TKA0, TKA2, and TKA4 positions, increased laxity at 30° (4.8° ± 1.9° versus 7.9° ± 2.3° versus 10.2° ± 2.0°; p < 0.001) and 60° (5.7° ± 2.7° versus 8.8° ± 2.9° versus 11.3° ± 2.9°; p < 0.001) was observed when the medial joint line was raised 2 and 4 mm. At 30°, this corresponds to an average increase of 64% (3.1°; p < 0.01) in mid-flexion laxity with a 2-mm raised joint line and a 111% (5.4°; p < 0.01) increase with a 4-mm raised joint line compared with the 9-mm baseline resection. No differences in coronal alignment were found between the knees implanted with kinematic alignment versus mechanical alignment at any flexion angle. The analytical model was consistent with the cadaveric findings and showed lengthening of the superficial MCL in mid-flexion., Conclusions: Despite a well-balanced knee in full extension and at 90° flexion, increased mid-flexion laxity in the coronal plane was evident in the specimens where the joint line was raised., Clinical Relevance: When recutting the distal and posterior femur and downsizing the femoral component, surgeons should be aware that this action might increase the laxity in mid-flexion, even if the knee is stable at 0° and 90°.
- Published
- 2018
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42. Surgical treatment of the Anterior Cruciate Ligament Rupture : where do we stand today?
- Author
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Verhelst PJ and Luyckx T
- Subjects
- Humans, Recovery of Function, Anterior Cruciate Ligament surgery, Anterior Cruciate Ligament Injuries surgery, Anterior Cruciate Ligament Reconstruction methods
- Abstract
The rupture of the anterior cruciate ligament is one of the most common orthopaedic injuries. This review gives an overview of the surgical treatment of the ACL rupture. A correct knowledge of the anatomy of the ACL is crucial in treating this injury. Recent studies describe the ACl as flat rather than divided in distinct structural bundles. Reconstructive and primary repair techniques can be used to approach this native anatomy. Reconstructive surgery of the ACL still is the golden standard in ACL surgery. An individualized approach is key and should be used. However, ACL reconstruction is not always a success. Return to preinjury of sports only reaches 65% and ACL-reconstructed knees are prone to osteoarthritis. Previous attempts at the primary repair of the ACL were archaic and had disappointing results. Modern diagnostics, operative and biological techniques and strict patient selection could initiate a revival of this technique.
- Published
- 2017
43. Modified anconeus muscle transfer as treatment of failed surgical release of lateral epicondylitis of the elbow.
- Author
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Luyckx T, Decramer A, Luyckx L, and Noyez J
- Abstract
The purpose of this study was to evaluate the safety and the effectiveness of a new modified anconeus transfer technique in revision surgery for refractory lateral epicondylitis of the elbow. A modified anconeus muscle transfer was performed in nine patients with persistent symptoms after previous surgical release of the common extensor origin. The original technique was modified by using only half of the anconeus muscle. Patients were clinically evaluated, including quickDASH score and grip strength measurement. At a mean follow up period of 36 months, 4 patients had an excellent result, 3 a good result and 1 a poor result. All patients rated their clinical situation as better than before surgery. All but one patient said to be happy with the result and they would undergo the procedure again. The mean quickDash score at the follow up was 10.6 (SD 14.4). No complications were observed. The modified Anconeus muscle transfer is a safe and effective procedure in patients with persistent lateral epicondylitis complaints after a previous surgical release.
- Published
- 2017
44. High strains near femoral insertion site of the superficial medial collateral ligament of the Knee can explain the clinical failure pattern.
- Author
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Luyckx T, Verstraete M, De Roo K, Van Der Straeten C, and Victor J
- Subjects
- Aged, Cone-Beam Computed Tomography, Humans, Imaging, Three-Dimensional, Isometric Contraction, Knee Joint physiology, Male, Medial Collateral Ligament, Knee diagnostic imaging, Medial Collateral Ligament, Knee injuries, Middle Aged, Stress, Mechanical, Knee Injuries etiology, Medial Collateral Ligament, Knee physiology
- Abstract
The three dimensional (3D) deformation of the superficial medial collateral ligament (sMCL) of the knee might play an important role in the understanding of the biomechanics of sMCL lesions. Therefore, the strain and deformation pattern of the sMCL during the range of motion were recorded in five cadaveric knees with digital image correlation. During knee flexion, the sMCL was found to deform in the three planes. In the sagittal plane, a rotation of the proximal part of the sMCL relative to the distal part occurred with the center of this rotation being the proximal tibial insertion site of the sMCL. This deformation generated high strains near the femoral insertion site of the sMCL. These strains were significantly higher than in the other parts and were maximal at 90° with on average +3.7% of strain and can explain why most lesions in clinical practice are seen in this proximal region. The deformation also has important implications for sMCL reconstruction techniques. Only a perfect anatomic restoration of the insertion sites of the sMCL on both the proximal and distal tibial insertion sites will be able to reproduce the isometry of the sMCL and thus provide the adequate stability throughout the range of motion. The fact that knee motion between 15° and 90° caused minimal strain in the sMCL might suggest that early passive range of motion in physical therapy postoperatively should have little risk of stretching a graft out in the case of an anatomical reconstruction. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:2016-2024, 2016., (© 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.)
- Published
- 2016
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45. Lower extremity muscle activation onset times during the transition from double-leg stance to single-leg stance in anterior cruciate ligament injured subjects.
- Author
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Dingenen B, Janssens L, Luyckx T, Claes S, Bellemans J, and Staes FF
- Subjects
- Adult, Ankle Joint innervation, Ankle Joint physiopathology, Central Nervous System physiopathology, Electromyography, Female, Hip Joint innervation, Hip Joint physiopathology, Humans, Knee Joint innervation, Knee Joint physiopathology, Lower Extremity innervation, Lower Extremity physiopathology, Male, Muscle, Skeletal innervation, Muscle, Skeletal physiopathology, Neuromuscular Junction physiopathology, Young Adult, Anterior Cruciate Ligament physiopathology, Anterior Cruciate Ligament Injuries, Muscle Contraction physiology, Postural Balance physiology, Posture physiology, Weight-Bearing physiology
- Abstract
The goal of this study was to evaluate muscle activation onset times (MAOT) of both legs during a transition task from double-leg stance (DLS) to single-leg stance (SLS) in anterior cruciate ligament injured (ACLI) (n=15) and non-injured control subjects (n=15) with eyes open and eyes closed. Significantly delayed MAOT were found in the ACLI group compared to the control group for vastus lateralis, vastus medialis obliquus, hamstrings medial, hamstrings lateral, tibialis anterior, peroneus longus and gastrocnemius in both vision conditions, for gluteus maximus and gluteus medius with eyes open and for tensor fascia latae with eyes closed. Within the ACLI group, delayed MAOT of tibialis anterior with eyes open and gastrocnemius with eyes closed were found in the injured leg compared to the non-injured leg. All other muscles were not significantly different between legs. In conclusion, the ACLI group showed delayed MAOT not only around the knee, but also at the hip and ankle muscles compared to the non-injured control group. No differences between both legs of the ACLI group were found, except for tibialis anterior and gastrocnemius. These findings indirectly support including central nervous system re-education training to target the underlying mechanisms of these altered MAOT after ACL injury., (Copyright © 2015 Elsevier B.V. All rights reserved.)
- Published
- 2015
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46. The role of the deep medial collateral ligament in controlling rotational stability of the knee.
- Author
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Cavaignac E, Carpentier K, Pailhé R, Luyckx T, and Bellemans J
- Subjects
- Aged, Aged, 80 and over, Arthroplasty, Replacement, Knee, Biomechanical Phenomena, Cadaver, Female, Humans, Joint Instability diagnosis, Joint Instability physiopathology, Knee Joint surgery, Male, Range of Motion, Articular, Collateral Ligaments surgery, Joint Instability surgery, Knee Joint physiopathology, Knee Prosthesis
- Abstract
Purpose: The tibial insertion of the deep medial collateral ligament (dMCL) is frequently sacrificed when the proximal tibial cut is performed during total knee arthroplasty. The role of the dMCL in controlling the knee's rotational stability is still controversial. The aim of this study was to quantify the rotational laxity induced by an isolated lesion of the dMCL as it occurs during tibial preparation for knee arthroplasty., Methods: An isolated resection of the deep MCL was performed in 10 fresh-frozen cadaver knees. Rotational laxity was measured during application of a standard 5.0 N.m rotational torque. Maximal tibial rotation was measured at different knee flexion angles using an image-guided navigation system (Medivision Surgetics system, Praxim, Grenoble, France) before and after dMCL resection., Results: In all cases, internal and external tibial rotation increased after dMCL resection. Total rotational laxity increased significantly for all knee flexion angles, with an average difference of +7.8° (SD 5.7) with the knee in extension, +8.9° (SD 1.9) in 30° flexion, +7° (SD 2.9) in 60° flexion and +5.3° (SD 2.8) in 90° flexion., Conclusions: Sacrificing the tibial insertion of the deep MCL increases rotational laxity of the knee by 5°-9°, depending on the knee flexion angle. Based on our findings, new surgical techniques and implants that preserve the dMCL insertion such as tibial inlay components should be developed. Further clinical evaluations are necessary.
- Published
- 2015
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47. Postural stability during the transition from double-leg stance to single-leg stance in anterior cruciate ligament injured subjects.
- Author
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Dingenen B, Janssens L, Luyckx T, Claes S, Bellemans J, and Staes FF
- Subjects
- Anterior Cruciate Ligament physiopathology, Female, Humans, Male, Movement, Young Adult, Anterior Cruciate Ligament Injuries, Knee Injuries physiopathology, Leg physiopathology, Postural Balance physiology
- Abstract
Background: An anterior cruciate ligament injury may lead to deteriorations in postural stability. The goal of this study was to evaluate postural stability during the transition from double-leg stance to single-leg stance of both legs in anterior cruciate ligament injured subjects and non-injured control subjects with a standardized methodology., Methods: Fifteen control subjects and 15 anterior cruciate ligament injured subjects (time after injury: mean (SD)=1.4 (0.7) months) participated in the study. Both groups were similar for age, gender, height, weight and body mass index. Spatiotemporal center of pressure outcomes of both legs of each subject were measured during the transition from double-leg stance to single-leg stance in eyes open and eyes closed conditions. Movement speed was standardized., Findings: The center of pressure displacement after a new stability point was reached during the single-leg stance phase was significantly increased in the anterior cruciate ligament injured group compared to the control group in the eyes closed condition (P<.001). No significant different postural stability outcomes were found between both legs within both groups (P>.05). No significant differences were found during the transition itself (P>.05)., Interpretation: The anterior cruciate ligament injured group showed postural stability deficits during the single-leg stance phase compared to the non-injured control group in the eyes closed condition. Using the non-injured leg as a normal reference when evaluating postural stability of the injured leg may lead to misinterpretations, as no significant differences were found between the injured and non-injured leg of the anterior cruciate ligament injured group., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
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- 2015
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48. Digital image correlation as a tool for three-dimensional strain analysis in human tendon tissue.
- Author
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Luyckx T, Verstraete M, De Roo K, De Waele W, Bellemans J, and Victor J
- Abstract
Background: Determining the mechanical behaviour of tendon and ligamentous tissue remains challenging, as it is anisotropic, non-linear and inhomogeneous in nature., Methods: In this study, three-dimensional (3D) digital image correlation (DIC) was adopted to examine the strain distribution in the human Achilles tendon. Therefore, 6 fresh frozen human Achilles tendon specimens were mounted in a custom made rig for uni-axial loading. 3D DIC measurements of each loading position were obtained and compared to 2 linear variable differential transformers (LVDT's)., Results: 3D DIC was able to calculate tendon strain in every region of all obtained images. The scatter was found to be low in all specimens and comparable to that obtained in steel applications. The accuracy of the 3D DIC measurement was higher in the centre of the specimen where scatter values around 0.03% strain were obtained. The overall scatter remained below 0.3% in all specimens. The spatial resolution of 3D DIC on human tendon tissue was found to be 0.1 mm(2). The correlation coefficient between the 3D DIC measurements and the LVDT measurements showed an excellent linear agreement in all specimens (R(2) = 0.99). Apart from the longitudinal strain component, an important transverse strain component was revealed in all specimens. The strain distribution of both components was of a strongly inhomogeneous nature, both within the same specimen and amongst different specimens., Conclusion: DIC proved to be a very accurate and reproducible tool for 3D strain analysis in human tendon tissue.
- Published
- 2014
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49. Does a conservative tibial cut in conventional total knee arthroplasty violate the deep medial collateral ligament?
- Author
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Maes M, Luyckx T, and Bellemans J
- Subjects
- Aged, Aged, 80 and over, Anatomy, Cross-Sectional, Cadaver, Female, Humans, Knee Joint anatomy & histology, Male, Medial Collateral Ligament, Knee anatomy & histology, Middle Aged, Photography, Arthroplasty, Replacement, Knee, Knee Joint surgery, Medial Collateral Ligament, Knee surgery, Tibia surgery
- Abstract
Purpose: Based on the anatomy of the deep medial collateral ligament (MCL), it was hypothesized that at least part of its cross-sectional insertion area is jeopardized while performing a standard tibial cut in conventional total knee arthroplasty (TKA). The aim of this study was to determine whether it is anatomically possible to preserve the tibial deep MCL insertion during conventional TKA., Methods: Thirty-three unpaired cadaveric knee specimens were used for this study. Knees with severe varus/valgus deformity or damage to the medial structures of the knee were excluded. In the first part of the study, the dimensions of the tibial insertion of the deep MCL and its relationship to the joint line were recorded. Next, the cross-sectional area of the deep MCL insertion was determined using calibrated digital photographic analysis. In the second part, the effect of a standard 9-mm 3° sloped tibial cut on the structural integrity of the deep MCL cross-sectional insertion area was determined using conventional instrumentation., Results: The proximal border of the deep MCL insertion site on the tibia was located on average 4.7 ± 1.2 mm distally to the joint line. After performing a standard 9-mm 3° sloped tibial cut, on average 54% of the deep MCL insertion area was resected. In 29% of the cases, the deep MCL insertion area was completely excised., Conclusion: The deep MCL cannot routinely be preserved in conventional TKA. The deep MCL insertion is at risk and may be jeopardized in case of a tibial cut 9 mm below the native joint line. As the deep MCL is a distinct medial stabilizer and plays an important role in rotational stability, this may have implications in future designs of both unicondylar and total knee arthroplasty, but further research is necessary.
- Published
- 2014
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50. The Segond fracture: a bony injury of the anterolateral ligament of the knee.
- Author
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Claes S, Luyckx T, Vereecke E, and Bellemans J
- Subjects
- Adolescent, Adult, Awards and Prizes, Cadaver, Female, Femur diagnostic imaging, Humans, Knee Injuries diagnostic imaging, Knee Injuries pathology, Knee Joint diagnostic imaging, Ligaments, Articular diagnostic imaging, Ligaments, Articular pathology, Male, Middle Aged, Radiography, Tibia anatomy & histology, Tibia diagnostic imaging, Tibial Fractures diagnostic imaging, Tibial Fractures pathology, Young Adult, Ligaments, Articular injuries, Tibial Fractures etiology
- Abstract
Purpose: The purpose of this study was to investigate the relation of the Segond fracture with the anterolateral ligament (ALL) of the knee., Methods: To identify the soft-tissue structure causative for the Segond fracture, a study was set up to compare anatomic details of the tibial insertion of the recently characterized ALL in cadaveric knees (n = 30) with radiologic data obtained from patients (n = 29) with a possible Segond fracture based on an imaging protocol search. The spatial relation of the ALL footprint with well-identifiable anatomic landmarks at the lateral aspect of the knee was determined, and this was repeated for the Segond fracture bed., Results: In all of the included cadaveric knees, a well-defined ALL was found as a distinct ligamentous structure connecting the lateral femoral epicondyle with the anterolateral proximal tibia. The mean distance of the center of the tibial ALL footprint to the center of the Gerdy tubercle (GT-ALL distance) measured 22.0 ± 4.0 mm. The imaging database search identified 26 patients diagnosed with a Segond fracture. The mean GT-Segond distance measured 22.4 ± 2.6 mm. The observed difference of 0.4 mm (95% confidence interval, -1.5 to 2.2 mm) between the GT-ALL distance and GT-Segond distance was neither statistically significant (P = .70) nor clinically relevant., Conclusions: The results of this study confirmed the hypothesis that the ALL inserts in the region on the proximal tibia from where Segond fractures consistently avulse, thus suggesting that the Segond fracture is actually a bony avulsion of the ALL., Clinical Relevance: Although the Segond fracture remains a useful radiographic clue for indirect detection of anterior cruciate ligament injuries, the Segond fracture should be considered a frank ligamentous avulsion itself., (Copyright © 2014 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
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