Publications
470 results found
Stephen JM, Kittl C, Williams A, et al., 2015, The effect of graft type and femoral positioning on patellofemoral contact pressure and kinematics after medial patellofemoral ligament reconstruction, British Association for Surgery of the Knee
Geraldes D, Hansen U, Amis A, 2015, Parametric analysis of glenoid implant design, European Society of Biomechanics 2015
Bonner TJ, Newell N, Karunaratne A, et al., 2015, Strain-rate sensitivity of the lateral collateral ligament of the knee, Journal of The Mechanical Behavior of Biomedical Materials, Vol: 41, Pages: 261-270, ISSN: 1751-6161
The material properties of ligaments are not well characterized at rates of deformation that occur during high-speed injuries. The aim of this study was to measure the material properties of lateral collateral ligament of the porcine stifle joint in a uniaxial tension model through strain rates in the range from 0.01 to 100/s. Failure strain, tensile modulus and failure stress were calculated. Across the range of strain rates, tensile modulus increased from 288 to 905 MPa and failure stress increased from 39.9 to 77.3 MPa. The strain-rate sensitivity of the material properties decreased as deformation rates increased, and reached a limit at approximately 1/s, beyond which there was no further significant change. In addition, time resolved microfocus small angle X-ray scattering was used to measure the effective fibril modulus (stress/fibril strain) and fibril to tissue strain ratio. The nanoscale data suggest that the contribution of the collagen fibrils towards the observed tissue-level deformation of ligaments diminishes as the loading rate increases. These findings help to predict the patterns of limb injuries that occur at different speeds and improve computational models used to assess and develop mitigation technology.
Keller R, Amis AA, 2015, Anatomy and Biomechanics of the Natural Knee and After TKR, The Unhappy Total Knee Replacement, Editors: Hirschmann, Becker, Publisher: Springer, Pages: 3-15, ISBN: 978-3-319-08098-7
This book addresses the need for improved diagnostic and treatment guidelines for patients in whom total knee arthroplasty (TKA) has had an unsatisfactory outcome. It opens by discussing the basics of TKA and the various causes of failure and pain. Diagnostic aspects are considered in detail, with attention to advances in clinical investigation, laboratory analysis and in particular, imaging techniques. In addition, helpful state of the art diagnostic algorithms are presented. Specific pathology-related treatment options, including conservative approaches and salvage and revision TKA strategies, are then explained, with identification of pitfalls and key points. A series of illustrative cases cover clinical scenarios frequently encountered in daily clinical practice. The evidence-based, clinically focused guidance provided in this book, written by internationally renowned experts, will assist surgeons in achieving the most effective management of these challenging cases.
Gregory TM, Sukjamsri C, Hansen U, et al., 2015, Glenoid Aseptic Loosening After Anatomical Shoulder Replacement: a Systematic Review of the Radiolucent Line Significance and of the Loosening Mechanisms, E-MEMOIRES DE L ACADEMIE NATIONALE DE CHIRURGIE, Vol: 14, Pages: 7-12, ISSN: 1634-0647
Puthumanapully PK, Harris SJ, Leong A, et al., 2014, A morphometric study of normal and varus knees, KNEE SURGERY SPORTS TRAUMATOLOGY ARTHROSCOPY, Vol: 22, Pages: 2891-2899, ISSN: 0942-2056
- Author Web Link
- Open Access Link
- Cite
- Citations: 26
Halewood C, Risebury M, Thomas NP, et al., 2014, Kinematic behaviour and soft tissue management in guided motion total knee replacement, KNEE SURGERY SPORTS TRAUMATOLOGY ARTHROSCOPY, Vol: 22, Pages: 3074-3082, ISSN: 0942-2056
- Author Web Link
- Cite
- Citations: 29
Hunt NC, Ghosh KM, Athwal KK, et al., 2014, Lack of evidence to support present medial release methods in total knee arthroplasty, KNEE SURGERY SPORTS TRAUMATOLOGY ARTHROSCOPY, Vol: 22, Pages: 3100-3112, ISSN: 0942-2056
- Author Web Link
- Cite
- Citations: 33
Stephen JM, Lumpaopong P, Dodds AL, et al., 2014, The effect of progressive tibial tuberosity medialisation and lateralisation on patellofemoral joint kinematics, contact mechanics and stability, American Journal of Sports Medicine, Vol: 43, Pages: 186-194, ISSN: 1552-3365
Background: Tibial tuberosity (TT) transfer is a common procedure to treat patellofemoral instability in patients with elevated TT–trochlear groove (TG) distances. However, the effects of TT lateralization or medialization on patellar stability, kinematics, and contact mechanics remain unclear.Hypothesis: Progressive medialization and lateralization will have increasingly adverse effects on patellofemoral joint kinematics, contact mechanics, and stability.Study Design: Controlled laboratory study.Methods: Eight fresh-frozen cadaveric knees were placed on a testing rig, with a fixed femur and tibia mobile through 90° of flexion. Individual quadriceps heads and the iliotibial band were separated and loaded with 205 N in anatomic directions using a weighted pulley system. Patellofemoral contact pressures and patellar tracking were measured at 0°, 10°, 20°, 30°, 60°, and 90° of flexion using pressure-sensitive film behind the patella and an optical tracking system. The intact knee was measured with and without a 10-N patellar lateral displacement load, and recordings were repeated after TT transfer of 5, 10, and 15 mm medially and laterally. Statistical analysis used repeated-measures analysis of variance, Bonferroni post hoc analysis, and Pearson correlations.Results: Tibial tuberosity lateralization significantly elevated lateral joint contact pressures, increased lateral patellar tracking, and reduced patellar stability (P < .048). There was a significant correlation between mean lateral contact pressure and the TT position (r = 0.810, P < .001) at 10°. Tibial tuberosity medialization reduced lateral contact pressures (P < .002) and did not elevate peak medial contact pressures (P > .11).Conclusion: Progressive TT lateralization elevated lateral contact pressures, increased lateral patellar tracking, and reduced patellar stability. Medial contact pressure and tracking did alter with progressive TT medialization, but t
Barcellona MG, Morrissey MC, Milligan P, et al., 2014, The effect of thigh muscle activity on anterior knee laxity in the uninjured and anterior cruciate ligament-injured knee, KNEE SURGERY SPORTS TRAUMATOLOGY ARTHROSCOPY, Vol: 22, Pages: 2821-2829, ISSN: 0942-2056
- Author Web Link
- Cite
- Citations: 17
Geraldes D, Hansen U, Amis A, 2014, A framework for parametric analysis of glenoid implant design, MECBioengineering 2014
Geraldes D, Hansen U, Jeffers J, et al., 2014, A framework for parametric analysis of glenoid implant design, International Society for Technology in Arthroplasty 2014
Kittl C, Weiler A, Amis AA, 2014, Anterolateral rotatory instability: Anatomy, biomechanics, and reconstruction, Arthroskopie, Vol: 27, Pages: 170-176, ISSN: 0933-7946
Background: Anterolateral rotatory instability (ALRI) of the knee consists of a translational and rotational component. It is widely accepted that anterior cruciate ligament (ACL) deficiency causes anterior tibial translation, but controversy exists regarding the peripheral structures restraining tibial internal rotation. These structures may be reconstructed using lateral extra-articular soft-tissue reconstruction. The principal behind these types of reconstruction is to tether the graft posterior to the transverse center of rotation, therefore, limiting internal tibial rotation and ultimately restraining the rotational component of the pivot shift test. Aim: The aim of the following paper is to provide a critical literature review regarding anatomy, biomechanics, and related types of reconstruction of the anterolateral side of the knee. Materials and methods: The article provides a critical review of the ALRI literature and takes into account the authors' own anatomical and biomechanical observations. Results: Based on this literature review, the anterolateral structures of the knee may be more important in restraining internal tibial rotation than previously thought. Conclusion: A combined intra-articular ACL and lateral extra-articular soft-tissue reconstruction may be desirable in revision ACL surgery and in patients presenting excessive ALRI following ACL rupture. © 2014 Springer-Verlag Berlin Heidelberg.
Tuncer M, Hansen UN, Amis AA, 2014, Prediction of structural failure of tibial bone models under physiological loads: Effect of CT density-modulus relationships, MEDICAL ENGINEERING & PHYSICS, Vol: 36, Pages: 991-997, ISSN: 1350-4533
- Author Web Link
- Cite
- Citations: 28
Ghosh KM, Blain AP, Longstaff L, et al., 2014, Can we define envelope of laxity during navigated knee arthroplasty?, KNEE SURGERY SPORTS TRAUMATOLOGY ARTHROSCOPY, Vol: 22, Pages: 1736-1743, ISSN: 0942-2056
- Author Web Link
- Cite
- Citations: 32
Amis AA, Arendt E, Deehan D, et al., 2014, The Medial Patellofemoral Ligament, Publisher: Springer Berlin Heidelberg
Halewood C, Samuelsson K, Kopf S, et al., 2014, How to do proper research, ESSKA Instructional Course Lecture Book Amsterdam 2014, Publisher: Springer, ISBN: 9783642539824
This book provides an update on a wide variety of hot topics in the field of knee surgery, sports trauma and arthroscopy, covering the latest developments in basic science and clinical and surgical methods.
Atallah L, Wiik A, Lo B, et al., 2014, Gait asymmetry detection in older adults using a light ear-worn sensor, PHYSIOLOGICAL MEASUREMENT, Vol: 35, Pages: N29-N40, ISSN: 0967-3334
- Author Web Link
- Cite
- Citations: 15
Gupte CM, Schaerf DA, Sandison A, et al., 2014, Neural Structures within Human Meniscofemoral Ligaments: A Cadaveric Study., ISRN Anatomy, Vol: 2014, ISSN: 2314-4726
Aim. To investigate the existence of neural structures within the meniscofemoral ligaments (MFLs) of the human knee. Methods. The MFLs from 8 human cadaveric knees were harvested. 5 μm sections were H&E-stained and examined under light microscopy. The harvested ligaments were then stained using an S100 monoclonal antibody utilising the ABC technique to detect neural components. Further examination was performed on 60–80 nm sections under electron microscopy. Results. Of the 8 knees, 6 were suitable for examination. From these both MFLs existed in 3, only anterior MFLs were present in 2, and an isolated posterior MFL existed in 1. Out of the 9 MFLs, 4 demonstrated neural structures on light and electron microscopy and this was confirmed with S100 staining. The ultrastructure of these neural components was morphologically similar to mechanoreceptors. Conclusion. Neural structures are present in MFLs near to their meniscal attachments. It is likely that the meniscofemoral ligaments contribute not only as passive secondary restraints to posterior draw but more importantly to proprioception and may therefore play an active role in providing a neurosensory feedback loop. This may be particularly important when the primary restraint has reduced function as in the posterior cruciate ligament—deficient human knee.
Newman SD, Lotfibakhshaiesh N, O'Donnell M, et al., 2014, Enhanced Osseous Implant Fixation with Strontium-Substituted Bioactive Glass Coating, TISSUE ENGINEERING PART A, Vol: 20, Pages: 1850-1857, ISSN: 1937-3341
The use of endosseous implants is firmly established in skeletal reconstructive surgery, with rapid and permanent fixation of prostheses being a highly desirable feature. Implant coatings composed of hydroxyapatite (HA) have become the standard and have been used with some success in prolonging the time to revision surgery, but aseptic loosening remains a significant issue. The development of a new generation of more biologically active coatings is a promising approach for tackling this problem. Bioactive glasses are an ideal candidate material due to the osteostimulative properties of their dissolution products. However, to date, they have not been formulated with stability to devitrification or thermal expansion coefficients (TECs) that are suitable for stable coating onto metal implants while still retaining their bioactive properties. Here, we present a strontium-substituted bioactive glass (SrBG) implant coating which has been designed to encourage peri-implant bone formation and with a TEC similar to that of HA. The coating can be successfully applied to roughened Ti6Al4V and after implantation into the distal femur and proximal tibia of twenty-seven New Zealand White rabbits for 6, 12, or 24 weeks, it produced no adverse tissue reaction. The glass dissolved over a 6 week period, stimulating enhanced peri-implant bone formation compared with matched HA coated implants in the contralateral limb. Furthermore, superior mechanical fixation was evident in the SrBG group after 24 weeks of implantation. We propose that this coating has the potential to enhance implant fixation in a variety of orthopedic reconstructive surgery applications.
Kondo E, Merican AM, Yasuda K, et al., 2014, Biomechanical Analysis of Knee Laxity With Isolated Anteromedial or Posterolateral Bundle-Deficient Anterior Cruciate Ligament, ARTHROSCOPY-THE JOURNAL OF ARTHROSCOPIC AND RELATED SURGERY, Vol: 30, Pages: 335-343, ISSN: 0749-8063
- Author Web Link
- Cite
- Citations: 28
Dodds AL, Halewood C, Gupte CM, et al., 2014, The anterolateral ligament ANATOMY, LENGTH CHANGES AND ASSOCIATION WITH THE SEGOND FRACTURE, BONE & JOINT JOURNAL, Vol: 96B, Pages: 325-331, ISSN: 2049-4394
- Author Web Link
- Cite
- Citations: 299
Stoddard JE, Deehan DJ, Bull AMJ, et al., 2014, No difference in patellar tracking between symmetrical and asymmetrical femoral component designs in TKA, KNEE SURGERY SPORTS TRAUMATOLOGY ARTHROSCOPY, Vol: 22, Pages: 534-542, ISSN: 0942-2056
- Author Web Link
- Cite
- Citations: 14
Merican AM, Ghosh KM, Baena FRY, et al., 2014, Patellar thickness and lateral retinacular release affects patellofemoral kinematics in total knee arthroplasty, KNEE SURGERY SPORTS TRAUMATOLOGY ARTHROSCOPY, Vol: 22, Pages: 526-533, ISSN: 0942-2056
- Author Web Link
- Cite
- Citations: 27
Gregory T, Hansen U, Khanna M, et al., 2014, A CT scan protocol for the detection of radiographic loosening of the glenoid component after total shoulder arthroplasty, Acta Orthopaedica, Vol: 85, Pages: 91-96, ISSN: 0001-6470
Background and purpose It is difficult to evaluate glenoid component periprosthetic radiolucencies in total shoulder arthroplasties (TSAs) using plain radiographs. This study was performed to evaluate whether computed tomography (CT) using a specific patient position in the CT scanner provides a better method for assessing radiolucencies in TSA.Methods Following TSA, 11 patients were CT scanned in a lateral decubitus position with maximum forward flexion, which aligns the glenoid orientation with the axis of the CT scanner. Follow-up CT scanning is part of our routine patient care. Glenoid component periprosthetic lucency was assessed according to the Molé score and it was compared to routine plain radiographs by 5 observers.Results The protocol almost completely eliminated metal artifacts in the CT images and allowed accurate assessment of periprosthetic lucency of the glenoid fixation. Positioning of the patient within the CT scanner as described was possible for all 11 patients. A radiolucent line was identified in 54 of the 55 observed CT scans and osteolysis was identified in 25 observations. The average radiolucent line Molé score was 3.4 (SD 2.7) points with plain radiographs and 9.5 (SD 0.8) points with CT scans(p = 0.001). The mean intra-observer variance was lower in the CT scan group than in the plain radiograph group (p = 0.001).Interpretation The CT scan protocol we used is of clinical value in routine assessment of glenoid periprosthetic lucency after TSA. The technique improves the ability to detect and monitor radiolucent lines and, therefore, possibly implant loosening also.
Stephen JM, Kader D, Lumpaopong P, et al., 2014, The Effect of Femoral Tunnel Position and Graft Tension on Patellar Contact Mechanics and Kinematics After Medial Patellofemoral Ligament Reconstruction, AMERICAN JOURNAL OF SPORTS MEDICINE, Vol: 42, Pages: 364-372, ISSN: 0363-5465
- Author Web Link
- Cite
- Citations: 114
Hunt NC, Ghosh KM, Blain AP, et al., 2014, How does laxity after single radius total knee arthroplasty compare with the native knee?, J. Orthop. Res., Vol: 32, Pages: 1208-1213, ISSN: 1554-527X
Athwal KK, Hunt NC, Davies AJ, et al., 2013, Clinical biomechanics of instability related to total knee arthroplasty, Clinical Biomechanics, ISSN: 0268-0033
Gregory TM, Sankey A, Augereau B, et al., 2013, Accuracy of Glenoid Component Placement in Total Shoulder Arthroplasty and Its Effect on Clinical and Radiological Outcome in a Retrospective, Longitudinal, Monocentric Open Study, PLOS ONE, Vol: 8, ISSN: 1932-6203
- Author Web Link
- Cite
- Citations: 43
Amis AA, 2013, Unicondylar knee replacement and the cruciate ligaments, Small Implants in Knee Reconstruction, Pages: 17-27, ISBN: 9788847026544
This chapter mainly addresses the way in which the actions of the cruciate ligaments affect the kinematics of the tibiofemoral joint after unicompartmental knee replacement (UKR). Although it is normal practise to excise one or both of the cruciate ligaments during total knee arthroplasty (TKA), this reflects the fact that, historically, TKA patients were severely disabled by their arthritis and so they did not demand high levels of function: pain relief was paramount. The degree of degenerative change in these osteoarthritic knees was such that the anterior cruciate ligament was usually absent, following a combination of soft-tissue degenerative changes associated with chronic inflammation and mechanical destruction mechanisms, such as sawing by the edges of the osteophytes that had formed around the antero-distal outlet of the femoral intercondylar notch. This has never been the case with UKR, as in these patients, who are often younger, only one compartment of the knee has arthritic damage severe enough to require arthroplasty. Therefore, the implants are required to work in harmony with the other structures of the knee and ideally with a high level of function.
This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.