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Glowacki J, Bartkowiak T, Paczos P, Mietlinski P, Zawadzki P, Lapaj L. Effect of screw angulation and multiple insertions on load-to-failure of polyaxial locking system. PLoS One 2023; 18:e0295526. [PMID: 38079421 PMCID: PMC10712845 DOI: 10.1371/journal.pone.0295526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Accepted: 11/21/2023] [Indexed: 12/18/2023] Open
Abstract
PURPOSE Polyaxial locking plates rely on the alignment between the thread-to-thread connections of the screw head and the plate hole. These implants have provided substantial support for surgeons. In particular, extended screw positioning have proven to be beneficial in the fixation of challenging fractures. This study aimed to investigate the mechanical properties of ChM 5.0 ChLP polyaxial screws inserted in off-axis trajectories, including multiple insertions and to correlate these parameters with the screw head and the plate hole thread-to-thread engagement. METHODS Polyaxial locking screws were inserted into the plates at various angles (0°,10°,15°, -15° off-axis). Multiple time inserted screws were placed firstly at 15°, then 0° and finally -15° off-axis in the same plate hole. A microCT scan of the plate-hole and screw-head interface was conducted before destructive tests. Representative screws from each group were also examined by Scanning Electron Microscope. RESULTS The standard insertion at 0° sustained the greatest maximum bending strength without relocation in the screw hole. Screws inserted at 10° and 15° (one time) showed a significant reduction in load-to-failure of up to 36% and 55%, (p = 0.001) (p = 0.001) respectively. Screws inserted at -15° after a maximum of three multiple insertions with angle shift, showed a total reduction in force of up to 70% (p = 0.001). A microCT analysis of thread engagement showed significant correlations. However, the results obtained for multiple insertions were highly variable. CONCLUSIONS ChM 5.0 ChLP polyaxial locking system has valuable properties that foster fracture fixation, providing various surgical options. Nevertheless, the freedom of off-axis placement and multiple insertions of the screws comes at the price of reduced force. When possible surgeons should minimize the angles of insertions.
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Affiliation(s)
- Jakub Glowacki
- Department of General Orthopaedics, Musculoskeletal Oncology and Trauma Surgery, Poznan University of Medical Sciences, Poznań, Poland
| | - Tomasz Bartkowiak
- Institute of Mechanical Technology, Poznan University of Technology, Poznań, Poland
| | - Piotr Paczos
- Institute of Applied Mechanics, Poznan University of Technology, Poznań, Poland
| | - Patryk Mietlinski
- Institute of Mechanical Technology, Poznan University of Technology, Poznań, Poland
| | - Pawel Zawadzki
- Institute of Mechanical Technology, Poznan University of Technology, Poznań, Poland
| | - Lukasz Lapaj
- Department of General Orthopaedics, Musculoskeletal Oncology and Trauma Surgery, Poznan University of Medical Sciences, Poznań, Poland
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Glowacki J, Bartkowiak T, Paczos P, Gapinski B, Mietlinski P, Zawadzki P, Weiss W, Lapaj L. Effect of screw angulation on the bending performance of polyaxial locking interfaces: a micro-CT evaluation. Sci Rep 2023; 13:21740. [PMID: 38066023 PMCID: PMC10709442 DOI: 10.1038/s41598-023-48791-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 11/30/2023] [Indexed: 12/18/2023] Open
Abstract
Polyaxial locking plates rely on a specific thread-to-thread interface of the screw head and the plate hole. The objective of this study was to evaluate the mechanical performance of single screw interfaces when inserted off-axis and to establish correlations between those parameters and the engagement of the screw head and the plate hole thread. Three polyaxial locking screw systems were inserted into the corresponding plates at various angles (0°, 5°, 10°, and 15° off-axis). The screws were tested until failure. A micro-CT was performed to examine the interface between the plate hole and the screw head. The standard insertion at 0° sustained the greatest maximum bending strength without relocation in the screw hole. Screws inserted at 15° showed a significant reduction in force of up to 44%, 55% and 57%, respectively. Micro-CT analysis of the interface showed a significant loss of thread engagement for off-axis insertion. Polyaxial plates offer additional advantages for off-axis placement of screws. However, this flexibility is related to a significant decrease in both thread engagement and bending strength compared to monoaxial insertion. Regardless the insertion angle, the loss of stability is comparable when screws are placed off-axis. Surgeons are advised to consider off-axis insertion as a salvage option, providing access to better bone stock.
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Affiliation(s)
- Jakub Glowacki
- Department of General Orthopaedics, Musculoskeletal Oncology and Trauma Surgery, Poznan University of Medical Sciences, Poznan, Poland.
| | - Tomasz Bartkowiak
- Institute of Mechanical Technology, Poznan University of Technology, Poznan, Poland
| | - Piotr Paczos
- Institute of Applied Mechanics, Poznan University of Technology, Poznan, Poland
| | - Bartosz Gapinski
- Institute of Mechanical Technology, Poznan University of Technology, Poznan, Poland
| | - Patryk Mietlinski
- Institute of Mechanical Technology, Poznan University of Technology, Poznan, Poland
| | - Pawel Zawadzki
- Institute of Mechanical Technology, Poznan University of Technology, Poznan, Poland
| | - Weronika Weiss
- Institute of Mechanical Technology, Poznan University of Technology, Poznan, Poland
| | - Lukasz Lapaj
- Department of General Orthopaedics, Musculoskeletal Oncology and Trauma Surgery, Poznan University of Medical Sciences, Poznan, Poland
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Pierret M, Favreau H, Bonnomet F, Elizondo Moreno D, Bahlouli N, Martz P, Ehlinger M. Comparison of five methods for locked-plate fixation of complex diaphyseal fractures. Orthop Traumatol Surg Res 2022; 108:103400. [PMID: 36096378 DOI: 10.1016/j.otsr.2022.103400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Revised: 05/03/2022] [Accepted: 05/11/2022] [Indexed: 02/03/2023]
Abstract
BACKGROUND Peri-prosthetic fractures (PPFs) are steadily rising in number due to population ageing and increased performance of joint replacement procedures. Although PPFs without implant loosening are usually managed by internal fixation, no consensus exists regarding the optimal construct. The primary objective of this study was to compare five constructs, and the secondary objective was to compare sub-groups of mono-cortical screw constructs, with the goal of identifying the method most appropriate for diaphyseal fracture fixation when prosthetic material is present within the intra-medullary canal. HYPOTHESIS The primary hypothesis was that fixation using bi-cortical screws, i.e., the current reference standard, was superior over other fixation methods. The secondary hypothesis was that adding double cerclage to mono-cortical screw fixation provided the greatest mechanical strength. MATERIALS AND METHODS Synthetic osteoporotic bone was used to compare five methods for locking-screw fixation of a femoral diaphyseal plate. One method involved bi-cortical screws and four methods mono-cortical screws, with no cerclage wire, a single cerclage wire on either side positioned near or at a distance from the fracture, and two cerclage wires on both sides of the fracture. A complex fracture was simulated by creating a 2-cm diaphyseal gap. Load-to-failure was determined by applying compression loading along the anatomical axis of the femur. RESULTS Bi-cortical screw fixation provided greater mechanical strength than did three of the four mono-cortical screw constructs. The exception was the mono-cortical-screw and double-cerclage construct, for which no significant difference was found compared to bi-cortical screw fixation. Thus, mono-cortical screw fixation with double cerclage may be the best alternative when presence of an implant in the intra-medullary canal precludes bi-cortical screw fixation. CONCLUSION The findings from this study have clear implications for clinical practice. The study hypotheses were partly confirmed. The absence of a significant difference between the reference-standard bi-cortical screw fixation method and mono-cortical screw fixation with double cerclage, combined with the results regarding the secondary objective, suggest that mono-cortical screws plus double cerclage deserve preference in patients with an intra-medullary implant. Clinical studies are needed to assess the results of this bench study. LEVEL OF EVIDENCE IV, bench study.
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Affiliation(s)
- Marie Pierret
- Service de Chirurgie Orthopédique et de Traumatologie, Hôpital de Hautepierre, Hôpitaux Universitaires de Strasbourg, 1 avenue Molière, 67098 Strasbourg cedex, France; Laboratoire ICube, Université de Strasbourg- CNRS, 2 rue Boussingault, 67000 Strasbourg, France
| | - Henri Favreau
- Service de Chirurgie Orthopédique et de Traumatologie, Hôpital de Hautepierre, Hôpitaux Universitaires de Strasbourg, 1 avenue Molière, 67098 Strasbourg cedex, France
| | - François Bonnomet
- Service de Chirurgie Orthopédique et de Traumatologie, Hôpital de Hautepierre, Hôpitaux Universitaires de Strasbourg, 1 avenue Molière, 67098 Strasbourg cedex, France
| | - Daniel Elizondo Moreno
- Laboratoire ICube, Université de Strasbourg- CNRS, 2 rue Boussingault, 67000 Strasbourg, France; Plateforme IRIS/ICube, Université de Strasbourg- CNRS, 1 place de l'hôpital, 67000 Strasbourg, France
| | - Nadia Bahlouli
- Laboratoire ICube, Université de Strasbourg- CNRS, 2 rue Boussingault, 67000 Strasbourg, France
| | - Pierre Martz
- CHU Dijon, service d'orthopédie traumatologie, 14 rue Paul Gaffarel, 21000 Dijon, France; Unité INSERM UMR CAPS U1093. UFR STAPS, - BP 27877, Campus Universitaire, 21078 Dijon Cedex, France
| | - Matthieu Ehlinger
- Service de Chirurgie Orthopédique et de Traumatologie, Hôpital de Hautepierre, Hôpitaux Universitaires de Strasbourg, 1 avenue Molière, 67098 Strasbourg cedex, France; Laboratoire ICube, Université de Strasbourg- CNRS, 2 rue Boussingault, 67000 Strasbourg, France.
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Takai H, Nonoue Y, Kitajima M, Hama S, Takahashi T. Total femur fixation using the "nail-plate docking technique" for ipsilateral femur shaft fracture. Trauma Case Rep 2022; 42:100722. [PMID: 36281428 DOI: 10.1016/j.tcr.2022.100722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/16/2022] [Indexed: 11/09/2022] Open
Abstract
In an aging society, the number of femoral fractures is increasing, as well as the incidence of periprosthetic fractures. These secondary fractures are often difficult to fixate stably because of the osteoporotic bone and the existence of the former implant. Herein, we present two cases of secondary femoral shaft fractures after osteosyntheses for distal femur fractures with polyaxial locking plates (Non-Contact-Bridging Distal Femur, NCB-DF®, ZimmerBIOMET, Winterthur, Switzerland). Antegrade intramedullary nails (Natural Nail®-GT Femoral, ZimmerBIOMET, Winterthur, Switzerland) were utilized without removal of the NCB-DFs. In these osteosyntheses, proximal locking screws of NCB-DFs were inserted and locked into the distal inter-locking holes of Natural Nails. This "nail-plate docking technique" could allow for more stable fixation of the whole femur with minimally invasive surgical intervention while preserving the existing implant. Although there are a few surgical technical knacks and pitfalls in inserting the screw, further fractures of the femur could also be prevented with this technique.
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Dhason R, Roy S, Datta S. Metal and composite bone plates for B1 periprosthetic femoral fracture in healthy and osteoporotic condition: A comparative biomechanical study. Int J Artif Organs 2022; 45:704-714. [DOI: 10.1177/03913988221108752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The major concern after total hip arthroplasty (THA) is the incidence of periprosthetic fracture in the weaker bone, which can lead to subsequent revision surgery. Achieving the suitable fixation without affecting the stability of the well-fixed prosthesis remains controversial. Most of the studies examined the behavior of the Periprosthetic Fracture (PF) fixation (Vancouver “B1” type) through computational and experimentation on healthy bone condition with metal plates. The aim of the present study is to analyze the influences of the metal and composite bone plate PF fixation on the axial and shear movement at the fracture site. The PF fixation constructs were modeled with medical graded stainless-steel plate (construct A), titanium plate (construct B) and carbon/epoxy composite bone plate (construct C) with 12 holes and a 4 mm fracture gap. Analysis was carried out for all the stages (stage 1—Normal bone, stage 2—THA, stage 3—Immediate Post-Operative (IPO), stage 4—Post-Operative (PO) and, stage 5—Healed Bone (HB)) under various loadings for intact and osteoporosis conditions. The results showed higher stress in cortical bone for stage 3, whereas in all the other stages lower stresses were experienced in the cortical and cancelous bone under peak load in construct C for osteoporosis model compared with other constructs. The present study suggested the construct C may be suitable for osteoporosis bone conditions.
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Affiliation(s)
- Raja Dhason
- Department of Mechanical Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, India
| | - Sandipan Roy
- Department of Mechanical Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, India
| | - Shubhabrata Datta
- Department of Mechanical Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, India
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Rau D, Rußow G, Heyland M, Wulsten D, Kösters C, Schmölz W, Märdian S. A New System for Periprosthetic Fracture Stabilization-A Biomechanical Comparison. J Clin Med 2022; 11:892. [PMID: 35160342 DOI: 10.3390/jcm11030892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 01/26/2022] [Accepted: 02/05/2022] [Indexed: 11/23/2022] Open
Abstract
In recent years, an increase in periprosthetic femur fractures has become apparent due to the increased number of hip replacements. In the case of Vancouver type B1 fractures, locking plate systems offer safe procedures. This study compared the distal lateral femur plate (LOQTEQ®, aap Implantate AG) with a standard L.I.S.S. LCP® (DePuy Synthes) regarding their biomechanical properties in fixation of periprosthetic femur fractures after hip arthroplasty. We hypothesized that the new LOQTEQ system has superior stability and durability in comparison. Eighteen artificial left femurs were randomized in two groups (Group A: LOQTEQ®; Group B: L.I.S.S. LCP®) and tested until failure. Failure was defined as 10° varus deformity and catastrophic implant failure (loosening, breakage, progressive bending). Axial stiffness, loads of failure, cycles of failure, modes of failure were recorded. The axial stiffness in Group A with 73.4 N/mm (SD +/− 3.0) was significantly higher (p = 0.001) than in Group B (40.7 N/mm (SD +/− 2.8)). Group A resists more cycles than Group B until 10° varus deformity. Catastrophic failure mode was plate breakage in Group A and bending in Group B. In conclusion, LOQTEQ® provides higher primary stability and tends to have higher durability.
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Marczyński W, Sobolewski A. Static and dynamic examination of a locking plate in various setups for the stabilization of bone shaft fractures, including periprosthetic. Med Rehabil 2021. [DOI: 10.5604/01.3001.0014.8186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Introduction: Hip and knee arthroplasty, formerly known as the “gold standard” in the treatment of articular cartilage damage, after a period of being highly popular, are changing the way they are perceived over time due to their related complications. The number of complications is directly proportional to the number of prostheses placed. This is the case of numerus arthroplasty surgeries, also involving other joints. Since there is no tissue compatibility between the metal prosthesis and the bone tissue, the former represents a negative biological element that hinders the healing of the fracture.
Objective of the study: The study aims at addressing the following questions: 1. What is the elasticity of the fixation with a locking plate depending on the number of screws in both fragments, in the case of interfractural diastasis?, 2. What is the elasticity of the fixation with a locking plate depending on the number of screws in both fragments, in the case of fracture-on-fracture compression? 3. What is the difference in elasticity of the fixation using the cable system on a fracture with prosthesis?, 4. Determining the influence of different stabilization setups with the locking plate screws on the spacing of the fracture on the static and dynamic experimental model, 5. Is it possible to achieve elasticity of the stabilization stimulating bone union in a plate-based fixation, and when?
Material and methods: The study was performed in the research laboratory of ChM. The subject of the study was the ChM 5.0 ChLP straight narrow compression locking plate with limited contact L-238, holes-15. The plate was mounted using ChM 3.5 locking screws: 5.0 ChLP 3.5 x 18T self-tapping screw and 5.0 ChLP 3.5 x 36T self-tapping screw. The test was carried out under static and dynamic conditions.
Results and Conclusions: 1. The elasticity of the fixation with a locking plate at the interfractural diastasis is inversely proportional to the number of screws (plate deflection), 2. The elasticity of the fixation with a locking plate at the fracture-on-fracture compression is inversely proportional to the number of screws (fracture-on-fracture compression), 3. Application of the “cable system” on the fracture with prosthesis and the derotation screw optimizes the elasticity of the fixation and seems to be an optimal solution (in periprosthetic fractures), 4. Studies on the experimental static and dynamic model demonstrated that placing screws in all the openings of the plate is a restrained/clinically useless fixation. 5. The elasticity of the stabilization stimulating bone union can be obtained in the plate fixation supported by the "cable system".
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Affiliation(s)
- Wojciech Marczyński
- Department of Orthopaedics, Medical Centre of Postgraduate Education, the Prof. Adam Gruca Public Teaching Hospital in Otwock, Poland and Military Institute of Medicine in Warsaw, Poland
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Hanke MS, Beckmann NA, Keel MJB, Siebenrock KA, Bastian JD. Application of the reversed LISS-DF technique in an elderly patient to salvage infection-related failure of trochanteric fracture fixation. Trauma Case Rep 2021; 32:100419. [PMID: 33665313 PMCID: PMC7900578 DOI: 10.1016/j.tcr.2021.100419] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/06/2021] [Indexed: 02/01/2023] Open
Abstract
Failure of cephalomedullary fixation in geriatric trochanteric fractures is a potential complication. Attempts have been made to optimize the implant fixation (e. g. cement augmentation) and several factors (e. g. malreduction, tip apex distance) have been identified as risk factors for failure. Nevertheless, if intramedullary fixation fails, it is often associated with bone defects in mostly preexisting poor bone-stock. Accordingly, conversion to total hip arthroplasty (THA) is recommended by some authors as the only valid treatment option. However, in specific situations (e. g. implant associated infection) conversion to THA might be less reasonable than an attempt to re-osteosynthesis. This article reports on the successful use of a reversed contralateral LISS-DF (LISS for the distal femur, DePuy Synthes, Zuchwil, Switzerland) application after failed cephalomedullary fixation and failed re-osteosynthesis using a blade plate in a trochanteric fracture in an elderly patient with additional implant associated infection.
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Affiliation(s)
- Markus Simon Hanke
- Department of Orthopaedic Surgery and Traumatology, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - Nicholas Andreas Beckmann
- Department of Orthopaedics and Trauma Surgery, Heidelberg University Hospital, Schlierbacher Landstr. 200A, 69118 Heidelberg, Germany
- Corresponding author.
| | - Marius Johann Baptist Keel
- Department of Orthopaedic Surgery and Traumatology, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - Klaus Arno Siebenrock
- Department of Orthopaedic Surgery and Traumatology, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - Johannes Dominik Bastian
- Department of Orthopaedic Surgery and Traumatology, Inselspital, Bern University Hospital, University of Bern, Switzerland
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Harb A, Welke B, Liodakis E, Razaeian S, Zhang D, Krettek C, Hurschler C, Hawi N. Biomechanical Assessment of Three Osteosynthesis Constructs by Periprosthetic Humerus Fractures. Adv Orthop 2020; 2020:8872419. [PMID: 33163236 DOI: 10.1155/2020/8872419] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Accepted: 10/12/2020] [Indexed: 11/18/2022] Open
Abstract
Background Biomechanical stability assessment of 3 different constructs for proximal fixation of a locking compression plate (LCP) in treating a Worland type C periprosthetic fracture after total shoulder arthroplasty. Methods 27 Worland type C fractures after shoulder arthroplasty in synthetic humeri were treated with 14-hole LCP that is proximally fixed using the following: (1) 1 × 1.5 mm cerclage wires and 2x unicortical-locking screws, (2) 3 × 1.5 mm cerclage wires, or (3) 2x bicortical-locking attachment plates. Torsional stiffness was assessed by applying an internal rotation moment of 5 Nm and then after unloading the specimen, an external rotation moment of 5 Nm at the same rate was applied. Axial stiffness was assessed by applying a 50 N preload, and then applying a cyclic load of 250 N, then increasing the load by 50 N each time, until a maximum axial load of 2500 N was reached or specimen failure occurred. Results With regard to internal as well as external rotational stiffness, group 1 showed a mean stiffness of 0.37 Nm/deg and 0.57 Nm/deg, respectively, group 2 had a mean stiffness of 0.51 Nm/deg and 0.39 Nm/deg, respectively, while group 3 had a mean stiffness of 1.34 Nm/deg and 1.31 Nm/deg, respectively. Concerning axial stiffness, group 1 showed an average stiffness of 451.0 N/mm, group 2 had a mean stiffness of 737.5 N/mm, whereas group 3 had a mean stiffness of 715.8 N/mm. Conclusion Group 3 displayed a significantly higher torsional stiffness while a comparable axial stiffness to group 2.
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Grünewald D, Langenmair E, Hirschmüller A, Maier D, Südkamp NP, Konstantinidis L. Biomechanical in vitro evaluation of a ready-to-use calcium phosphate cement implanted to augment intramedullary nail fixation of a three-part humeral head fracture model. Proc Inst Mech Eng H 2019; 233:706-711. [PMID: 31064313 DOI: 10.1177/0954411919848625] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The aim of this study was the dynamic biomechanical evaluation of a ready-to-use oil-based calcium phosphate cement paste implanted to augment intramedullary nail fixation of a three-part humeral head fracture model. Fractures in the osteoporotic bone are often fractures of the proximal humerus. Secondary fracture displacements due to cut-out in osteoporotic bone have been observed in up to 13% of cases. Procedures have been developed to augment fracture fixation with polymethylmethacrylate to increase stability, but there are still unsolved challenges relating to its material-specific properties. Calcium phosphate cement could be a biological alternative in the augmentation of osteoporotic fractures because of its more favourable material properties. Fracture fixation was performed on eight pairs of human cadaveric bones to stabilize a standardized three-part humeral head fracture model by implantation of the Targon® PH (Braun-Aesculap AG, Tuttlingen, Germany) intramedullary nail and insertion of three head screws and two bicortical shaft screws. The procedure was randomized, and one bone of each pair received calcium phosphate cement augmentation. Custom-made cannulated screws with an open lateral slot facilitated augmentation, making it possible to cement the threaded portion of the screw (1-mL calcium phosphate cement/screw). After the calcium phosphate cement had hardened, the humeri were subjected to dynamic axial loading. Load was progressively increased, monitored by ultrasound-based motion analysis, and total deformation was recorded. Load testing continued until implant failure. The augmented group withstood significantly more cycles before implant failure. The average initial stiffness showed a significant difference between the two study groups. Ultrasonic sensor technology was used to measure angular displacement during testing and a significant difference was found. Calcium phosphate cement offers a potential alternative to implant augmentation in the treatment of osteoporotic humeral head fractures. Future studies are required to confirm these observations clinically in vivo.
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Affiliation(s)
- Dag Grünewald
- 1 Department of Orthopaedics and Trauma Surgery, Berufsgenossenschaftliche Unfallklinik Frankfurt am Main, Frankfurt am Main, Germany
| | - Elia Langenmair
- 2 Department of Orthopaedics and Trauma Surgery, Loretto-Krankenhaus Freiburg, Freiburg im Breisgau, Germany
| | - Anja Hirschmüller
- 3 Department of Orthopaedics and Trauma Surgery, Medical Center, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Germany
| | - Dirk Maier
- 3 Department of Orthopaedics and Trauma Surgery, Medical Center, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Germany
| | - Norbert P Südkamp
- 3 Department of Orthopaedics and Trauma Surgery, Medical Center, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Germany
| | - Lukas Konstantinidis
- 3 Department of Orthopaedics and Trauma Surgery, Medical Center, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Germany
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Wang K, Kenanidis E, Miodownik M, Tsiridis E, Moazen M. Periprosthetic fracture fixation of the femur following total hip arthroplasty: A review of biomechanical testing - Part II. Clin Biomech (Bristol, Avon) 2019; 61:144-162. [PMID: 30579137 DOI: 10.1016/j.clinbiomech.2018.12.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 11/21/2018] [Accepted: 12/04/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND Periprosthetic femoral fracture is a severe complication of total hip arthroplasty. A previous review published in 2011 summarised the biomechanical studies regarding periprosthetic femoral fracture and its fixation techniques. Since then, there have been several commercially available fracture plates designed specifically for the treatment of these fractures. However, several clinical studies still report failure of fixation treatments used for these fractures. METHODS The current literature on biomechanical models of periprosthetic femoral fracture fixation since 2010 to present is reviewed. The methodologies involved in the experimental and computational studies of periprosthetic femoral fracture fixation are described and compared with particular focus on the recent developments. FINDINGS Several issues raised in the previous review paper have been addressed by current studies; such as validating computational results with experimental data. Current experimental studies are more sophisticated in design. Computational studies have been useful in studying fixation methods or conditions (such as bone healing) that are difficult to study in vivo or in vitro. However, a few issues still remain and are highlighted. INTERPRETATION The increased use of computational studies in investigating periprosthetic femoral fracture fixation techniques has proven valuable. Existing protocols for testing periprosthetic femoral fracture fixation need to be standardised in order to make more direct and conclusive comparisons between studies. A consensus on the 'optimum' treatment method for periprosthetic femoral fracture fixation needs to be achieved.
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Affiliation(s)
- Katherine Wang
- Department of Mechanical Engineering, University College London, Torrington Place, London WC1E 7JE, UK
| | - Eustathios Kenanidis
- Department of Mechanical Engineering, University College London, Torrington Place, London WC1E 7JE, UK; Academic Orthopaedics Department, Papageorgiou General Hospital & CORE Lab at CIRI AUTH, Aristotle University Medical School, University Campus 54 124, Thessaloniki, Greece
| | - Mark Miodownik
- Department of Mechanical Engineering, University College London, Torrington Place, London WC1E 7JE, UK
| | - Eleftherios Tsiridis
- Academic Orthopaedics Department, Papageorgiou General Hospital & CORE Lab at CIRI AUTH, Aristotle University Medical School, University Campus 54 124, Thessaloniki, Greece
| | - Mehran Moazen
- Department of Mechanical Engineering, University College London, Torrington Place, London WC1E 7JE, UK.
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Abstract
BACKGROUND: Hip arthroplasties are increasing worldwide resulting in an increasing number of periprosthetic fractures. These fractures are difficult to treat with various the different fixation or revision options described, many of which have high complication rates. PURPOSE: To investigate whether our described method of treating periprosthetic fractures is an effective, safe and reproducible method of treating patients. METHODS: We describe the largest series of a cable plate fixation system combined with a single cortical strut allograft to treat patients with periprosthetic fractures of the hip (Unified Classification System B1 and selected B2, C and D). RESULTS: Between July 2006 and March 2015, 28 patients were treated using this method. The mean follow-up was 2.2 years (3 months to 9 years). The mean Oxford Hip Score (OHS) at final follow-up was 32 and the mean modified Harris Hip Score (mHHS) 67. There were 3 complications including 1 failure that required revision surgery, 1 case of infection successfully treated with debridement, antibiotics and retention, and a case of discomfort from the metalwork which we managed conservatively. CONCLUSION: This method of anatomical restoration of the femur with dual-plane fixation is a highly effective method of treating this complex group of patients, and should be considered as a first line of treatment. It shows that there is a role for successful treatment with internal fixation of certain B2, C and D fractures with this technique.
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Affiliation(s)
- Jonathan R Manara
- Department of Trauma and Orthopaedics, Royal United Hospital, Bath, UK
| | - John A Mathews
- Department of Trauma and Orthopaedics, Royal United Hospital, Bath, UK
| | - Harvey S Sandhu
- Department of Trauma and Orthopaedics, Royal United Hospital, Bath, UK
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Kim MB, Cho JW, Lee YH, Shon WY, Park JW, Kim J, Oh JK. Locking attachment plate fixation around a well-fixed stem in periprosthetic femoral shaft fractures. Arch Orthop Trauma Surg 2017; 137:1193-200. [PMID: 28689273 DOI: 10.1007/s00402-017-2745-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Indexed: 10/19/2022]
Abstract
INTRODUCTION Periprosthetic fractures are difficult to manage. Plating technique has been considered a reliable form of management of periprosthetic fractures with a well-fixed stem, but a dependable and stable method of plate fixation to the bone is lacking. This study reports the clinical results using a locking attachment plate (LAP) instead of cable fixation to fix locking plates to a periprosthetic femoral shaft fracture. MATERIALS AND METHODS Nineteen patients with periprosthetic femoral shaft fractures around well-fixed stemmed implants were studied between August 2012 and December 2014. Patients were followed up for at least 1 year postoperatively. Median age was 74 years (range 56-96 years). Fractures were classified according to the Unified Classification System, Vancouver classification, and Su classification. PROCEDURE Open reduction was performed under minimal incision and the locking plate was fixed to the lateral cortex of the femoral shaft. The part of the shaft without a stem was fixed to the plate using 5.0-mm locking screws, and the part with an underlying stem was fixed using 3.5-mm locking screws through the LAP instead of cables. Postoperatively, patients were managed using general principles for femoral shaft fractures. RESULTS Average follow-up was 16 months (range 12-36 months). All cases achieved fracture healing without loss of reduction. There were no cases of implant breakage or stem loosening at final follow-up. The average number of LAPs per fixation construct was 2.1 (range 1-4), and the average number of 3.5-mm locking screws through each LAP was 3.3 (range 2-4). The average value of plate screw density was 0.55 (range 0.37-0.8), and the average working length was four holes (range 2-8). CONCLUSIONS Using the LAP to manage periprosthetic fractures with a well-fixed stem could obviate the need for cable around the stem area and yield acceptable outcomes.
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Wähnert D, Grüneweller N, Gehweiler D, Brunn B, Raschke MJ, Stange R. Double plating in Vancouver type B1 periprosthetic proximal femur fractures: A biomechanical study. J Orthop Res 2017; 35:234-239. [PMID: 27061941 DOI: 10.1002/jor.23259] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 04/04/2016] [Indexed: 02/04/2023]
Abstract
Periprosthetic hip fractures are an increasing problem in modern orthopedic and trauma surgery. Many options for the operative treatment are available to the surgeon ranging from modern variable angular systems to standard plates, screws, and cerclages. However, there is no gold standard and therefore, the aim of this study, was to investigate the biomechanical characteristics of double plating versus a lateral standard plate in a Vancouver B1 fracture model. Ten 4th generation composite femora were used to implant cementless total hip prosthesis and create Vancouver B1 periprosthetic fractures. Afterwards, the osteotomies were fixed using the locking compression plate in combination with the locking attachment plate (LCP, LAP, DePuy Synthes, Solothurn, Switzerland)-group I. Group II additionally achieved a 5-hole 4.5/5.0 mm LCP anteriorly. Each construct was cyclically loaded to failure in axial compression. Axial construct stiffness was 50.87 N/mm (SD 1.61) for group I compared to 738.68 N/mm (SD 94.8) for group II, this difference was statistically significant (p = 0.016). The number of cycles to failure was also significant higher for group II (2,375 vs. 13,000 cycles; p = 0.016). Double plating can significantly increase construct stiffness and stability, and thus, is an option in the treatment of complex periprosthetic fractures, in revision surgery and for patients with the inability to partial weight bear. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:234-239, 2017.
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Affiliation(s)
- Dirk Wähnert
- Department of Trauma, Hand and Reconstructive Surgery, University Hospital Muenster, Albert-Schweitzer-Campus 1, Building W1, 48149, Muenster, Germany
| | - Niklas Grüneweller
- Department of Trauma, Hand and Reconstructive Surgery, University Hospital Muenster, Albert-Schweitzer-Campus 1, Building W1, 48149, Muenster, Germany
| | - Dominic Gehweiler
- Department of Trauma, Hand and Reconstructive Surgery, University Hospital Muenster, Albert-Schweitzer-Campus 1, Building W1, 48149, Muenster, Germany
| | - Benjamin Brunn
- Department of Trauma, Hand and Reconstructive Surgery, University Hospital Muenster, Albert-Schweitzer-Campus 1, Building W1, 48149, Muenster, Germany
| | - Michael J Raschke
- Department of Trauma, Hand and Reconstructive Surgery, University Hospital Muenster, Albert-Schweitzer-Campus 1, Building W1, 48149, Muenster, Germany
| | - Richard Stange
- Department of Trauma, Hand and Reconstructive Surgery, University Hospital Muenster, Albert-Schweitzer-Campus 1, Building W1, 48149, Muenster, Germany
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Konstantinidis L, Schmidt B, Bernstein A, Hirschmüller A, Schröter S, Südkamp NP, Helwig P. Plate fixation of periprosthetic femur fractures: What happens to the cement mantle? Proc Inst Mech Eng H 2016; 231:138-142. [PMID: 28013577 DOI: 10.1177/0954411916682769] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Osteosynthesis of periprosthetic femur fractures by screw fixation around the implanted prosthetic stem is currently regarded as the biomechanically superior option compared with cerclage. The aim of this biomechanical study was damage analysis of the cement mantle after revision screw insertion. A prosthetic stem (Bicontact) was implanted in 20 cadaveric femora in cemented technique. A locking compression plate (Synthes) was then applied to the lateral femur at the level of the prosthetic stem. The method of plate fixation to the femur was assigned randomly to three groups: bicortical non-locking screws, monocortical locking screws, and bicortical locking screws. This was followed by applying a fluctuating axial load (2100 N, 0.5 Hz) for 20,000 cycles. After testing, macroscopic and microscopic evaluations of the cement mantle were conducted. Cracks formed in the cement mantle in 14% of the 80 screw holes. The type of screw (bicortical or monocortical; locking or non-locking) had no significant effect on the number of cracks (p = 0.52). The relationship between manifestation of crack damage and cement mantle thickness was not significant (p = 0.36), whereas the relationship between crack formation and screw position was significant (p = 0.019). Those screws whose circumference was only partially within the cement mantle yielded a significantly lower number of cracks compared with screws positioned completely within the cement mantle or even touching the prosthetic stem. In order to reduce the incidence of crack formation in the cement mantle during plate osteosynthesis of periprosthetic femur fractures, the screws should not be either placed within the cement mantle or make direct contact with the stem.
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Affiliation(s)
- Lukas Konstantinidis
- 1 Clinic for Orthopaedics and Traumatology, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany
| | - Benjamin Schmidt
- 2 Clinic for Anesthesiology and Intensive Care Medicine, University Hospital Leipzig, Leipzig, Germany
| | - Anke Bernstein
- 1 Clinic for Orthopaedics and Traumatology, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany
| | - Anja Hirschmüller
- 1 Clinic for Orthopaedics and Traumatology, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany
| | - Steffen Schröter
- 3 Department of Traumatology and Reconstructive Surgery, BG Trauma Center Tübingen, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Norbert Paul Südkamp
- 1 Clinic for Orthopaedics and Traumatology, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany
| | - Peter Helwig
- 4 Clinic for orthopedics and traumatology, Clinic Heidenheim, Heidenheim, Germany
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Yeo I, Rhyu KH, Kim SM, Park YS, Lim SJ. High union rates of locking compression plating with cortical strut allograft for type B1 periprosthetic femoral fractures. Int Orthop 2016; 40:2365-71. [PMID: 26759257 DOI: 10.1007/s00264-015-3107-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 12/29/2015] [Indexed: 10/22/2022]
Abstract
PURPOSE Unified classification system (UCS) type B1 periprosthetic femoral fractures are associated with many complications, and management decisions continue to be controversial. The purpose of this study was to evaluate outcomes of UCS type B1 periprosthetic femoral fractures treated by locking compression plating with strut allograft augmentation. MATERIALS AND METHODS We retrospectively reviewed 17 consecutive UCS type B1 periprosthetic femoral fractures treated by open reduction and internal fixation using a lateral locking compression plate supplemented with an anterior cortical strut allograft. There was one man and 16 women with an average age of 74 years (range, 57-92 years). All had a cementless hip arthroplasty, and eight of the arthroplasties were revisions. RESULTS The mean duration of follow-up was 28 months (range, 12-74 months). All 17 fractures healed successfully at a mean of 20 weeks (range, 12-30 weeks). The mean post-operative Harris hip score was 86 points (range, 77-95 points). No mechanical complications such as failure of plate or screws and malalignment were noted. According to the graft-remodeling classification of Emerson et al., a partial bridging was observed in nine and a complete bridging in eight. Two patients required a removal of the plate due to irritation of the iliotibial band. No femoral stem loosening or deep infection was observed. CONCLUSION Our findings indicate that open reduction and internal fixation of UCS type B1 periprosthetic femoral fractures using a lateral locking compression plate supplemented with anterior cortical strut allograft provides adequate mechanical stability of fracture fixation and enhances the fracture healing.
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17
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Abstract
Fixation techniques of periprosthetic fractures are far from ideal although the number of this entity is rising. The presence of an intramedullary implant generates its own fracture characteristics since stiffness is altered along the bone shaft and certain implant combinations affect load resistance of the bone. Influencing factors are cement fixation of the implant, intramedullary locking and extramedullary or intramedullary localization of the implant and the cortical thickness of the surrounding bone. Cerclage wires are ideally suited to fix radially displaced fragments around an intramedullary implant but they are susceptible to axial and torsional load. Screws should be added if these forces have to be neutralized. Stability of the screw fixation itself can be enhanced by embracement configuration around the intramedullary implant. Poor bone stock quality, often being present in metaphyseal areas limits screw fixation. Cement augmentation is an attractive option in this field to enhance screw purchase.
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Affiliation(s)
- Mark Lenz
- Department of Trauma, Hand and Reconstructive Surgery, University Hospital Jena, Jena, Germany.
| | - Wolfgang Lehmann
- Department of Trauma Surgery, Orthopaedics and Plastic Surgery, University of Göttingen Medical School, Göttingen, Germany
| | - Dirk Wähnert
- Department of Trauma, Hand and Reconstructive Surgery, University Hospital Münster, Münster, Germany
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18
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Abstract
This article is concerned with the search for threshold values for bone quality beyond which the risk of fixation failure increased. For trochanteric fractures we recognized a BMD lower than 250mg/cm(3) as an additional risk for cut out. For medial femoral neck fractures since joint replacement surgery is available and produces excellent functional results, we see no indication for further differentiation or analysis of bone quality in relation to fracture fixation. In the area of osteoporotic vertebral body fractures, there are many experimental studies that try to identify BMD limits of screw fixation in the cancellous bone on the basis of QCT analysis. However, these values have not yet been introduced for application in clinical practice. In case of indication for surgical fixation, we favor minimally invasive, bisegmental, fourfold dorsal instrumentation with screw-augmentation for a T-value less than -2.0 SD (DXA analysis, total hip or total lumbar spine). For proximal humerus fractures, BMD value of 95mg/cm(3) could be seen as a threshold value below which the risk of failure rises markedly. In relation to osteoporotic distal radius fractures, based on our clinical experience and scientific analyses there are virtually no restrictions as far as bone quality is concerned on the application of palmar locking implants in the surgical management of distal radius fractures. Optimization of preoperative diagnostics might help to revise the treatment algorithm to take bone density into account, thus reducing the risk of failure and, at the same time, acquiring additional data for future reference.
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Affiliation(s)
- Lukas Konstantinidis
- Klinik für Orthopädie und Unfallchirurgie, Universitätsklinik Freiburg, Hugstetterstr. 55, 79106Freiburg, Germany
| | - Peter Helwig
- Klinik für Orthopädie und Unfallchirurgie, Universitätsklinik Freiburg, Hugstetterstr. 55, 79106Freiburg, Germany
| | - Anja Hirschmüller
- Klinik für Orthopädie und Unfallchirurgie, Universitätsklinik Freiburg, Hugstetterstr. 55, 79106Freiburg, Germany
| | - Elia Langenmair
- Klinik für Orthopädie und Unfallchirurgie, Universitätsklinik Freiburg, Hugstetterstr. 55, 79106Freiburg, Germany
| | - Norbert P Südkamp
- Klinik für Orthopädie und Unfallchirurgie, Universitätsklinik Freiburg, Hugstetterstr. 55, 79106Freiburg, Germany
| | - Peter Augat
- Institut für Biomechanik, Berufsgenossenschaftliche Unfallklinik Murnau & Paracelsus Medical University, Salzburg, Prof. Kuentscher Str. 8, 82418Murnau, Germany.
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19
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Hohloch L, Konstantinidis L, Wagner FC, Strohm PC, Südkamp NP, Reising K. Biomechanical comparison of different external fixator configurations for stabilization of supracondylar humerus fractures in children. Clin Biomech (Bristol, Avon) 2016; 32:118-23. [PMID: 26743869 DOI: 10.1016/j.clinbiomech.2015.12.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2014] [Revised: 12/14/2015] [Accepted: 12/14/2015] [Indexed: 02/07/2023]
Abstract
BACKGROUND Currently, closed reduction and percutaneous pinning are considered the treatment of choice for displaced supracondylar humerus fractures. However, indications exist for the use of external fixation with Schanz screws. In this in vitro study, we evaluate the biomechanical properties of a new variation for external fixation and compare them to an established construct. METHODS Twenty distal cadaver humeri (10 pairs) were allocated to 2 groups. The humeri of the first group were fixed by an external fixator consisting of Schanz screws and an oblique K-wire inserted from the distal radial cortex of the humerus, those of the second group were fixed by a new variation with the oblique K-wire inserted from the distal ulnar cortex of the humerus. Displacement and stiffness in static loading in internal and external rotation, as well as in extension and flexion were evaluated and compared. FINDINGS The variation of the external fixator of the second group proved to be statistically significantly superior to the variation of the first group in internal rotation loading (p>0.05). In sagittal loading conditions and external rotation loading, the variations were equally stable (p>0.05). There was no significant effect of the samples' bone density on displacement and stiffness values in any direction of loading. INTERPRETATION In cases of pediatric supracondylar humerus fractures when an external fixator is used for osteosynthesis, the insertion of an additional ulnarly inserted anti-rotation K-wire should be preferred to a radially inserted one as it reduces secondary displacement of the distal fragment.
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Affiliation(s)
- Lisa Hohloch
- Department of Surgery Clinic for Orthopedic and Trauma Surgery, Freiburg University Hospital, Freiburg, Germany
| | - Lukas Konstantinidis
- Department of Surgery Clinic for Orthopedic and Trauma Surgery, Freiburg University Hospital, Freiburg, Germany
| | - Ferdinand C Wagner
- Department of Surgery Clinic for Orthopedic and Trauma Surgery, Freiburg University Hospital, Freiburg, Germany
| | - Peter C Strohm
- Department of Surgery Clinic for Orthopedic and Trauma Surgery, Freiburg University Hospital, Freiburg, Germany
| | - Norbert P Südkamp
- Department of Surgery Clinic for Orthopedic and Trauma Surgery, Freiburg University Hospital, Freiburg, Germany
| | - Kilian Reising
- Department of Surgery Clinic for Orthopedic and Trauma Surgery, Freiburg University Hospital, Freiburg, Germany.
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Griffiths JT, Taheri A, Day RE, Yates PJ. Better Axial Stiffness of a Bicortical Screw Construct Compared to a Cable Construct for Comminuted Vancouver B1 Proximal Femoral Fractures. J Arthroplasty 2015; 30:2333-7. [PMID: 26239233 DOI: 10.1016/j.arth.2015.06.060] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 06/22/2015] [Accepted: 06/23/2015] [Indexed: 02/01/2023] Open
Abstract
The aim of this study was to biomechanically evaluate the Locking attachment plate (LAP) construct in comparison to a Cable plate construct, for the fixation of periprosthetic femoral fractures after cemented total hip arthroplasty. Each construct incorporated a locking compression plate with bi-cortical locking screws for distal fixation. In the Cable construct, 2 cables and 2 uni-cortical locking screws were used for proximal fixation. In the LAP construct, the cables were replaced by a LAP with 4 bi-cortical locking screws. The LAP construct was significantly stiffer than the cable construct under axial load with a bone gap (P=0.01). The LAP construct offers better axial stiffness compared to the cable construct in the fixation of comminuted Vancouver B1 proximal femoral fractures.
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Affiliation(s)
| | - Arash Taheri
- Fremantle Hospital, Fremantle, Western Australia
| | - Robert E Day
- Medical Engineering and Physics Department, Royal Perth Hospital, Perth, Western Australia, Australia
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Lampropoulou-Adamidou K, Tosounidis TH, Kanakaris NK, Ekkernkamp A, Wich M, Giannoudis PV. The outcome of Polyax Locked Plating System for fixation distal femoral non-implant related and periprosthetic fractures. Injury 2015; 46 Suppl 5:S18-24. [PMID: 26343298 DOI: 10.1016/j.injury.2015.08.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The objective of this study was to report on the safety, efficacy and clinical outcomes of the Polyax Locked Plating System (Biomet, Warsaw, IN, USA) in the management of acute (non-implant related and periprosthetic) distal femoral fractures. We retrospectively reviewed 71 patients with 73 distal femoral fractures. Thirty-three of the included fractures occurred around previously placed implants. The average patients' age was 67 years (range 18-98). There were 7 early postoperative complications (9.5%) including one deep surgical site infection, 2 pulmonary embolisms and 4 urinary or respiratory infections. At final follow-up (mean 12, range 9-55 months) all fractures progressed to clinical and radiological union. However, major revision surgery for healing problems was required in 5 cases (6.8%) and minor in 3 cases (4.1%). The average time to healing was 6 (range 3-23) months. Angulation less than 5 degrees in any plane was observed in 66 cases (89.7%), within 5-10 degrees in 5 cases (7.3%) and within 10-15 degrees in 2 cases (2.9%). The mean pre-injury and final follow-up values of Glasgow Outcome Scale were 1.5(1-3) and 1.7(1-3) respectively. Overall 61 patients (83.53%) retained their pre-injury activity status. The Polyax Locked Plating System offers a safe and efficient fixation in distal femoral fractures.
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Affiliation(s)
- Kalliopi Lampropoulou-Adamidou
- Academic Department of Trauma & Orthopaedic Surgery, University of Leeds, Clarendon Wing, Floor A, Great George Street, Leeds General Infirmary, LS1 3EX Leeds, UK
| | - Theodoros H Tosounidis
- Academic Department of Trauma & Orthopaedic Surgery, University of Leeds, Clarendon Wing, Floor A, Great George Street, Leeds General Infirmary, LS1 3EX Leeds, UK; NIHR Leeds Biomedical Research Unit, Chapel Allerton Hospital, West Yorkshire, LS7 4SA Leeds, UK
| | - Nikolaos K Kanakaris
- Academic Department of Trauma & Orthopaedic Surgery, University of Leeds, Clarendon Wing, Floor A, Great George Street, Leeds General Infirmary, LS1 3EX Leeds, UK
| | - Axel Ekkernkamp
- Department of Trauma and Orthopedic Surgery, Unfallkrankenhaus Berlin, Warener Str. 7, 12683 Berlin, Germany
| | - Michael Wich
- Department of Trauma and Orthopedic Surgery, Unfallkrankenhaus Berlin, Warener Str. 7, 12683 Berlin, Germany; Klinikum Dahme-Spreewald, Koepenicker Str. 29, 15711 Koenigs Wusterhausen, Germany
| | - Peter V Giannoudis
- Academic Department of Trauma & Orthopaedic Surgery, University of Leeds, Clarendon Wing, Floor A, Great George Street, Leeds General Infirmary, LS1 3EX Leeds, UK; NIHR Leeds Biomedical Research Unit, Chapel Allerton Hospital, West Yorkshire, LS7 4SA Leeds, UK.
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Lewis GS, Caroom CT, Wee H, Jurgensmeier D, Rothermel SD, Bramer MA, Reid JS. Tangential Bicortical Locked Fixation Improves Stability in Vancouver B1 Periprosthetic Femur Fractures: A Biomechanical Study. J Orthop Trauma 2015; 29:e364-70. [PMID: 26053467 DOI: 10.1097/BOT.0000000000000365] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVES The biomechanical difficulty in fixation of a Vancouver B1 periprosthetic fracture is purchase of the proximal femoral segment in the presence of the hip stem. Several newer technologies provide the ability to place bicortical locking screws tangential to the hip stem with much longer lengths of screw purchase compared with unicortical screws. This biomechanical study compares the stability of 2 of these newer constructs to previous methods. METHODS Thirty composite synthetic femurs were prepared with cemented hip stems. The distal femur segment was osteotomized, and plates were fixed proximally with either (1) cerclage cables, (2) locked unicortical screws, (3) a composite of locked screws and cables, or tangentially directed bicortical locking screws using either (4) a stainless steel locking compression plate system with a Locking Attachment Plate (Synthes) or (5) a titanium alloy Non-Contact Bridging system (Zimmer). Specimens were tested to failure in either axial or torsional quasistatic loading modes (n = 3) after 20 moderate load preconditioning cycles. Stiffness, maximum force, and failure mechanism were determined. RESULTS Bicortical constructs resisted higher (by an average of at least 27%) maximum forces than the other 3 constructs in torsional loading (P < 0.05). Cables constructs exhibited lower maximum force than all other constructs, in both axial and torsional loading. The bicortical titanium construct was stiffer than the bicortical stainless steel construct in axial loading. CONCLUSIONS Proximal fixation stability is likely improved with the use of bicortical locking screws as compared with traditional unicortical screws and cable techniques. In this study with a limited sample size, we found the addition of cerclage cables to unicortical screws may not offer much improvement in biomechanical stability of unstable B1 fractures.
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Gwinner C, Märdian S, Dröge T, Schulze M, Raschke MJ, Stange R. Bicortical screw fixation provides superior biomechanical stability but devastating failure modes in periprosthetic femur fracture care using locking plates. Int Orthop 2015; 39:1749-55. [PMID: 25947899 DOI: 10.1007/s00264-015-2787-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2015] [Accepted: 04/01/2015] [Indexed: 10/23/2022]
Abstract
PURPOSE The incidence of periprosthetic fractures is inevitably increasing. Sufficient stabilisation and proper screw placement next to large-volume implants remains difficult. Modern locking plates allow polyaxial, thus bicortical, screw placement around a prosthetic stem. This study analysed the biomechanical properties of different screw configurations in a locking plate construct of a periprosthetic femoral fracture model. METHODS A total of 20 Sawbones were used to stabilise a Vancouver-B1 femoral fracture with a locking plate using either four monocortical screws or three bicortical screws for proximal fixation. These were loaded with an increasing axial compression until failure. RESULTS Bicortical screw purchase was significantly superior to monocortical regarding load to failure (1,510 N ± 284 N versus 2,350 N ± 212 N, p < 0.001) and maximal number of cycles (6803 ± 760 versus 4041 ± 923, p < 0.001). However, the mode of failure in the bicortical group was a severe comminuted fracture pattern as opposed to the monocortical group in which a pull-out of the screws without further damage to the bone was observed. CONCLUSIONS Bicortical screw placement enhances the primary stability in treating periprosthetic femoral fractures. Notably, the mode of failure may limit the salvage options in case of revision surgery.
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Wagner FC, Konstantinidis L, Hohloch N, Hohloch L, Suedkamp NP, Reising K. Biomechanical evaluation of two innovative locking implants for comminuted olecranon fractures under high-cycle loading conditions. Injury 2015; 46:985-9. [PMID: 25771445 DOI: 10.1016/j.injury.2015.02.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 02/05/2015] [Accepted: 02/08/2015] [Indexed: 02/02/2023]
Abstract
INTRODUCTION The relatively high complication rate after fixation of olecranon fractures has led to an increasing application of anatomically pre-contoured locking plate systems. The purpose of the present study was to conduct a biomechanical comparison of olecranon osteosyntheses by applying the Olecranon VA-LCP and the 3.5mm LCP Hook Plate (LCP, locking compression plate) to an unstable fracture model under high-cycle loading conditions. METHODS After creating an unstable fracture (Schatzker type B), osteosynthesis was performed on eight pairs of fresh-frozen cadaveric ulnae by application of either the Olecranon VA-LCP (Synthes, Solothurn, Switzerland) or the 3.5mm LCP Hook Plate (Synthes, Solothurn, Switzerland). Loading (50,000 alternating loads, cyclic and sinusoidal 10-300 N) was conducted by application of tensile load with the elbow in 90° flexion to simulate the tensile strength of the triceps brachii. For statistical analysis, angular displacement in the region of the humeral trochlea was taken as a measure of olecranon dislocation. RESULTS In Group 1 (Olecranon VA-LCP), a median angular displacement of 0.36° (minimum 0.10°; maximum 0.80°) was observed after 500 alternating loads. In Group 2 (3.5-mm LCP Hook Plate), the medial displacement was 0.80° (minimum 0.13°; maximum 2.72°). The difference was nonsignificant (p = 0.128). The mean value for angular displacement in Group 1 after 50,000 cycles was 0.80° (minimum 0.31°; maximum 1.99°), whereas in Group 2 a mean angular displacement of 2.02° (minimum 0.71°; maximum 6.40°) was recorded. The difference was statistically significant (p = 0.017). In Group 2, implant failure in the form of proximal plate pullout occurred in one construct after 756 cycles. CONCLUSION A significantly higher biomechanical stability can be achieved in the fixation of unstable olecranon fractures by application of the Olecranon VA-LCP rather than the 3.5mm LCP Hook Plate.
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Affiliation(s)
- F C Wagner
- Department of Orthopedic and Trauma Surgery, Freiburg University Medical Center, Freiburg, Germany.
| | - L Konstantinidis
- Department of Orthopedic and Trauma Surgery, Freiburg University Medical Center, Freiburg, Germany
| | - N Hohloch
- Department of Orthopedic and Trauma Surgery, Freiburg University Medical Center, Freiburg, Germany
| | - L Hohloch
- Department of Orthopedic and Trauma Surgery, Freiburg University Medical Center, Freiburg, Germany
| | - N P Suedkamp
- Department of Orthopedic and Trauma Surgery, Freiburg University Medical Center, Freiburg, Germany
| | - K Reising
- Department of Orthopedic and Trauma Surgery, Freiburg University Medical Center, Freiburg, Germany
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Abstract
We are currently facing an epidemic of periprosthetic fractures around the hip. They may occur either during surgery or post-operatively. Although the acetabulum may be involved, the femur is most commonly affected. We are being presented with new, difficult fracture patterns around cemented and cementless implants, and we face the challenge of an elderly population who may have grossly deficient bone and may struggle to rehabilitate after such injuries. The correct surgical management of these fractures is challenging. This article will review the current choices of implants and techniques available to deal with periprosthetic fractures of the femur.
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Affiliation(s)
- A T Yasen
- University College London Hospitals, 235 Euston Road, London NW1 2BU, UK
| | - F S Haddad
- University College London Hospitals, 235 Euston Road, London NW1 2BU, UK
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Yasen AT, Haddad FS. The management of type B1 periprosthetic femoral fractures: when to fix and when to revise. Int Orthop 2014; 39:1873-9. [PMID: 25512137 DOI: 10.1007/s00264-014-2617-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Accepted: 11/25/2014] [Indexed: 10/24/2022]
Abstract
The incidence of periprosthetic fractures around total hip arthroplasty is increasing as patient longevity rises and the number of patients with hip implants continues to grow. Type B1 periprosthetic femoral fractures are associated with a well-fixed stem and have traditionally been treated with internal fixation. However, there are a subset of these fractures which fare badly when internal fixation is undertaken, and revision of the femoral component to a long-stemmed implant may be more appropriate. We look at the traditional methods of fixation, and the evidence and indications for revision of these fractures.
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Affiliation(s)
- Adam T Yasen
- Department of Trauma and Orthopaedics, University College London Hospital, 235 Euston Road, London, NW1 2BU, UK,
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El-Zayat BF, Efe T, Ruchholtz S, Khatib S, Timmesfeld N, Krüger A, Zettl R. Mono- versus polyaxial locking plates in distal femur fractures - a biomechanical comparison of the Non-Contact-Bridging- (NCB) and the PERILOC-plate. BMC Musculoskelet Disord 2014; 15:369. [PMID: 25373872 PMCID: PMC4232626 DOI: 10.1186/1471-2474-15-369] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 10/27/2014] [Indexed: 12/01/2022] Open
Abstract
Background The aim of this cadaveric study was to compare a polyaxial (NCB®, Zimmer) to a fixed-angle monoaxial locking plate (PERILOC®, Smith & Nephew) in comminuted fractures of the distal femur regarding stability of the construct. Up to date there is no published biomechanical data concerning polyaxial plating in cadaveric distal femurs. Methods Fourteen formalin fixed femora were scanned by dual-energy x-ray absorptiometry. As fracture model an unstable supracondylar comminuted fracture was simulated. Fractures were pairwise randomly fixed either with a mono- (group A) or a polyaxial (group B) distal femur plate. The samples were tested in a servohydraulic mechanical testing system starting with an axial loading of 200 N following an increase of 200 N in every step with 500 cycles in every sequence up to a maximum of 2 000 N. The end points were implant failure or relevant loss of reduction. Data records included for each specimen time, number of cycles, axial load and axial displacement. Statistical analysis was performed using the exact Wilcoxon signed rank test. Results The mean donor age at the time of death was 75 years. The bone mass density (BMD) of the femurs in both groups was comparable and showed no statistically significant differences. Five bones failed before reaching the maximum applied force of 2000 N. Distribution curves of all samples in both groups, showing the plastic deformation in relation to the axial force, showed no statistically significant differences. Conclusions Operative stabilization of distal femur fractures can be successfully and equally well achieved using either a monoaxial or a polyaxial locking plate. Polyaxial screw fixation may have advantages if intramedullary implants are present. Electronic supplementary material The online version of this article (doi:10.1186/1471-2474-15-369) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Bilal Farouk El-Zayat
- Department of Orthopaedics and Rheumatology, University Hospital Marburg, Baldingerstrasse, 35043 Marburg, Germany.
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Sariyilmaz K, Dikici F, Dikmen G, Bozdag E, Sunbuloglu E, Bekler B, Yazicioglu O. The effect of strut allograft and its position on Vancouver type B1 periprosthetic femoral fractures: a biomechanical study. J Arthroplasty 2014; 29:1485-90. [PMID: 24656637 DOI: 10.1016/j.arth.2014.02.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 01/19/2014] [Accepted: 02/13/2014] [Indexed: 02/01/2023] Open
Abstract
The aim of this study is to assess the biomechanical advantage of adding strut allograft and the effect of its position on the construct in Vancouver type B1 fractures. Fifteen forth-generation synthetic femurs were used and created a fracture model at the tip of prosthesis, and subsequently fixated with a lateral plate only, lateral plate and medial strut, lateral plate and anterior strut. Rotational and axial tests were performed. In all loading tests, the plate with medial strut group was stiffer than the other constructs and had higher failure load values and had less displacement in the fracture site. A combination of a plate with a medial strut allograft provides more mechanical stability on periprosthetic femoral fractures near the tip of a total hip arthroplasty.
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Affiliation(s)
- Kerim Sariyilmaz
- Department of Orthopedics and Traumatology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Fatih Dikici
- Department of Orthopedics and Traumatology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Goksel Dikmen
- Department of Orthopedics and Traumatology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Ergun Bozdag
- Laboratory of Biomechanics and Strength of Materials, Faculty of Mechanical Engineering, Istanbul Technical University, Istanbul, Turkey
| | - Emin Sunbuloglu
- Laboratory of Biomechanics and Strength of Materials, Faculty of Mechanical Engineering, Istanbul Technical University, Istanbul, Turkey
| | - Bugra Bekler
- Laboratory of Biomechanics and Strength of Materials, Faculty of Mechanical Engineering, Istanbul Technical University, Istanbul, Turkey
| | - Onder Yazicioglu
- Department of Orthopedics and Traumatology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
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Lenz M, Perren SM, Gueorguiev B, Richards RG, Hofmann GO, Fernandez dell'Oca A, Höntzsch D, Windolf M. A biomechanical study on proximal plate fixation techniques in periprosthetic femur fractures. Injury 2014; 45 Suppl 1:S71-5. [PMID: 24252576 DOI: 10.1016/j.injury.2013.10.027] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
INTRODUCTION Proximal plate fixation is a crucial factor in osteosynthesis of periprosthetic femur fractures. Stability and strength of different fixation concepts for proximal plate fixation were compared. MATERIALS AND METHODS Twelve fresh frozen, bone mineral density matched human femora, instrumented with cemented hip endoprosthesis were osteotomized simulating a Vancouver B1 fracture. Specimens were instrumented with locking compression plates, fixed proximally with either locking attachment plate (LAP), monocortical screws, cerclage plus monocortical screws (1cerclage) or cerclages only (4cerclages). Cyclic testing was performed with monotonically increasing load until failure. Relative movements at the proximal plate-femur interface were registered by motion tracking. RESULTS The LAP construct exhibited a significantly longer cumulative survival (failure criterion 1mm separation at the proximal plate fixation) compared to the monocortical (p=0.048) and 4cerclages constructs (p=0.012) but not to 1cerclage constructs. CONCLUSION Bicortical screw anchorage improves proximal plate fixation in periprosthetic fractures. The cerclage-screw combination is a valuable alternative especially in osteoporotic bone.
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Affiliation(s)
- Mark Lenz
- AO Research Institute Davos, Clavadelerstrasse 8, CH-7270 Davos-Platz, Switzerland; Department of Trauma, Hand and Reconstructive Surgery, Friedrich-Schiller-University Jena, Erlanger Allee 101, D-07747 Jena, Germany.
| | - Stephan M Perren
- AO Research Institute Davos, Clavadelerstrasse 8, CH-7270 Davos-Platz, Switzerland.
| | - Boyko Gueorguiev
- AO Research Institute Davos, Clavadelerstrasse 8, CH-7270 Davos-Platz, Switzerland.
| | - Robert G Richards
- AO Research Institute Davos, Clavadelerstrasse 8, CH-7270 Davos-Platz, Switzerland.
| | - Gunther O Hofmann
- Department of Trauma, Hand and Reconstructive Surgery, Friedrich-Schiller-University Jena, Erlanger Allee 101, D-07747 Jena, Germany.
| | | | - Dankward Höntzsch
- Department of Medical Technology Development, BG Trauma Hospital Tübingen, Schnarrenbergstrasse 95, D-72076 Tübingen, Germany.
| | - Markus Windolf
- AO Research Institute Davos, Clavadelerstrasse 8, CH-7270 Davos-Platz, Switzerland.
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Hanschen M, Aschenbrenner IM, Fehske K, Kirchhoff S, Keil L, Holzapfel BM, Winkler S, Fuechtmeier B, Neugebauer R, Luehrs S, Liener U, Biberthaler P. Mono- versus polyaxial locking plates in distal femur fractures: a prospective randomized multicentre clinical trial. Int Orthop 2013; 38:857-63. [PMID: 24326361 DOI: 10.1007/s00264-013-2210-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Accepted: 11/15/2013] [Indexed: 11/25/2022]
Abstract
PURPOSE Treatment of complex fractures of the distal femur utilizing monoaxial locking plates (e.g. Less Invasive Stabilisation System, LISS®, Synthes) is considered to be superior to conventional plating systems. Due to the limitation that the thread forces the screw into pre-determined positions, modifications have been made to allow screw positioning within a range of 30° (Non Contact Bridging, NCB®-DF, Zimmer). For the first time, this multicenter prospective randomized clinical trial (RCT) investigates the outcome of LISS® vs. NCB®-DF treatment following complex fractures of the distal femur. METHODS Since June 2008, 27 patients with a fracture of the distal femur (AO ASIF 33-A-C and periprosthetic fractures) were enrolled in this study by four university trauma centres in southern Germany. Clinical (e.g. range of motion, Oxford knee score, Tegner score) and radiological (e.g. axis deviation, secondary loss of realignment) follow-ups were conducted one and six weeks, as well as three, six, and 12 months after the operation. RESULTS This study comprises data of 27 patients (8 male, 19 female; 15 NCB®-DF, 12 LISS®). Polyaxial osteosynthesis using the NCB® system tended to result in better functional knee scores and a higher range of motion. Interestingly, fracture union tended to be more rapid using the polyaxial plating system. CONCLUSIONS We present the analysis of a multicenter prospective RCT to compare the monoaxial LISS® vs. the polyaxial NCB®-DF treatment following complex fractures of the distal femur. NCB®-DF treatment tended to result in better functional and radiological outcomes than LISS® treatment. LEVEL OF EVIDENCE Level I.
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Affiliation(s)
- Marc Hanschen
- Department of Trauma Surgery, Klinikum rechts der Isar, Technical University Munich, Ismaninger Strasse 22, 81675, Munich, Germany,
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Abstract
Periprosthetic fractures are increasing not only due to the demographic development with high life expectancy, the increase in osteoporosis and increased prosthesis implantation but also due to increased activity of the elderly population. The therapeutic algorithms are manifold but general valid rules for severe fractures are not available. The most commonly occurring periprosthetic fractures are proximal and distal femoral fractures but in the clinical routine fractures of the tibial head, ankle, shoulder, elbow and on the borders to other implants (peri-implant fractures) and complex interprosthetic fractures are being seen increasingly more. It is to be expected that in the mid-term further options, such as cement augmentation of cannulated polyaxial locking screws will extend the portfolio of implants for treatment of periprosthetic fractures. The aim of this review article is to present the new procedures for osteosynthesis of periprosthetic fractures.
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Affiliation(s)
- M J Raschke
- Klinik und Poliklinik für Unfall-, Hand- und Wiederherstellungschirurgie, Universitätsklinikum Münster, Waldeyerstraße 1, 48149, Münster, Deutschland.
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Wähnert D, Schröder R, Schulze M, Westerhoff P, Raschke M, Stange R. Biomechanical comparison of two angular stable plate constructions for periprosthetic femur fracture fixation. Int Orthop 2014; 38:47-53. [PMID: 24114243 DOI: 10.1007/s00264-013-2113-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Accepted: 09/08/2013] [Indexed: 10/26/2022]
Abstract
PURPOSE Fractures of the femur associated with total hip arthroplasty are a significant concern in orthopaedic and trauma surgery. However, little is known about the different biomechanical properties of internal fixation systems in combination with periprosthetic fractures. In this study two new internal fixation systems for periprosthetic fractures are investigated using a cadaver fracture model simulating a Vancouver B1 periprosthetic femur fracture. METHODS Nine pairs of fresh-frozen cadaver femurs were scanned by dual X-ray absorptiometry. Cementless total hip prostheses were implanted and a periprosthetic femur fracture was simulated. Fractures were randomly fixed either with the fixed angle locking attachment plate (LAP®, Depuy Synthes®, Solothurn, Switzerland) or the variable angle non-contact bridging plate (NCB®, Zimmer GmbH, Winterthur, Switzerland). Each construct was cyclically loaded to failure in axial compression. RESULTS Axial stiffness and cycles to failure were significantly higher in the NCB group. Both systems were able to be fixed well around the femoral stem. CONCLUSION The two different internal fixation systems for periprosthetic fractures differed significantly in our setup. The non-contact bridging plate system revealed significantly higher failure load and may be the preferred option where high stability and load capacity is needed right after operation.
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Bastian JD, Butscher A, Bigolin G, Zumstein MA, Nötzli HP. Extracortical plate fixation with new plate inserts and cerclage wires for the treatment of periprosthetic hip fractures. Int Orthop 2014; 38:489-94. [PMID: 24091416 DOI: 10.1007/s00264-013-2114-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Accepted: 09/08/2013] [Indexed: 10/26/2022]
Abstract
PURPOSE Fixation of periprosthetic hip fractures with intracortical anchorage might not be feasible in cases with bulky implants and/or poor bone stock. METHODS Rotational stability of new plate inserts with extracortical anchorage for cerclage fixation was measured and compared to the stability found using a standard technique in a biomechanical setup using a torsion testing machine. In a synthetic PUR bone model, transverse fractures were fixed distally using screws and proximally by wire cerclages attached to the plates using "new" (extracortical anchorage) or "standard" (intracortical anchorage) plate inserts. Time to fracture consolidation and complications were assessed in a consecutive series of 18 patients (18 female; mean age 81 years, range 55-92) with periprosthetic hip fractures (ten type B1, eight type C-Vancouver) treated with the new device between July 2003 and July 2010. RESULTS The "new" device showed a higher rotational stability than the "standard" technique (p < 0.001). Fractures showed radiographic consolidation after 14 ± 5 weeks (mean ± SD) postoperatively in patients. Revision surgery was necessary in four patients, unrelated to the new technique. CONCLUSION In periprosthetic hip fractures in which fixation with intracortical anchorage using conventional means might be difficult due to bulky revision stems and/or poor bone stock, the new device may be an addition to the range of existing implants.
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Konstantinidis L, Papaioannou C, Blanke P, Hirschmüller A, Südkamp NP, Helwig P. Failure after osteosynthesis of trochanteric fractures. Where is the limit of osteoporosis? Osteoporos Int 2013; 24:2701-6. [PMID: 23702701 DOI: 10.1007/s00198-013-2392-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Accepted: 04/23/2013] [Indexed: 10/26/2022]
Abstract
SUMMARY The aim of this study is to identify osteoporosis values, beyond which there is a high risk of osteosynthesis failure. Bone mineral density (BMD) of 30 cadaveric femora with a pertrochanteric fracture osteotomy was correlated to the risk of cut out after osteosynthesis on a biomechanical testing approach. For a BMD less than 250 mg/cm(3), there is a high risk of fixation failure after surgical treatment of pertrochanteric fractures. This value can be regarded as a reference value for future experimental and clinical studies. INTRODUCTION Despite continuous modification of intramedullary load carriers for the surgical stabilization of trochanteric fractures, cut out remains the most frequent complication. The aim of this experimental study was to identify threshold osteoporosis values, beyond which there is a high risk of osteosynthesis failure. METHODS Bone mineral density (BMD) of 30 cadaveric femora was recorded for the femoral head by QCT measurement. Subsequently, a standardized osteotomy mimicking an unstable trochanteric type fracture was stabilized by intramedullary nailing. The constructs were loaded axially at a force of 2,100 N up to 20,000 cycles. Cut out at the femoral head was documented by radiograph. Statistical evaluation of the cohort group was performed by calculation of relative risk in relation to the BMD values. RESULTS In total, there were six cases of cut out after 10,000 cycles. The incidence of cut out for BMD less than 250 mg/cm(3) was 0.55 (5 of 9) and for BMD greater than 250 mg/cm(3), it was 0.05 (1 of 21). Therefore, the relative risk of cut out for BMD <250 mg/cm(3) is 11× greater than for a BMD >250 mg/cm(3). After 20,000 cycles, an additional test caused one cut out (relative risk of cut out for a BMD <250 mg/cm(3) 5.8). CONCLUSIONS For a BMD less than 250 mg/cm(3), there is a high risk of fixation failure after surgical treatment of pertrochanteric fractures. Although this value is based on an experimental in vitro study design with all its associated limitations, it can be regarded as a reference value for future experimental and clinical studies.
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Affiliation(s)
- L Konstantinidis
- Department of Orthopedics and Traumatology, Albert-Ludwigs-University Freiburg, Freiburg im Breisgau, Germany,
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Konstantinidis L, Papaioannou C, Hirschmüller A, Pavlidis T, Schroeter S, Südkamp NP, Helwig P. Intramedullary nailing of trochanteric fractures: central or caudal positioning of the load carrier? A biomechanical comparative study on cadaver bones. Injury 2013; 44:784-90. [PMID: 23395417 DOI: 10.1016/j.injury.2012.12.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2012] [Revised: 12/01/2012] [Accepted: 12/22/2012] [Indexed: 02/02/2023]
Abstract
BACKGROUND Current recommendations with regard to central or caudal positioning of the femur head carrier in the management of trochanteric fractures are contradictory. METHODS A standardised pertrochanteric osteotomy was stabilised in 15 pairs of cadaver femurs by means of intramedullary osteosynthesis (5xPFN-A-Synthes, 5xIntertan-Smith&Nephew, 5xTargon-PF-Aesculap). For each pair randomised central (group A) or caudal (group B) implantation of the femoral neck component was performed. Subsequently, the constructs were axially loaded to 2100N. In the absence of cut out after 20,000 cycles, load was increased to a maximum force of 3100N. Angular displacement was recorded based on ultrasound. Migration of the load carrier in the femoral head was monitored radiologically. FINDINGS DISPLACEMENT No significant difference between groups (p>0.15) was found for the first 50 load cycles. A significantly greater degree of varus deformity was observed in group A (p=0.049) after 2000 load cycles and became more apparent as the number of load cycles increased (after 6000 cycles p=0.039, after 20,000 cycles p=0.034, after 22,000 cycles p=0.016). Angular displacement in the other two planes did not differ significantly across groups. CUT OUT: Migration of the load carrier in the femoral head was not significantly different for the two groups. Overall cut out occurred in 9 constructs, 3 in group A and 6 in group B. The difference in cut-out rate was not significant (p=0.213, chi-squared test). CONCLUSION Biomechanical superiority can be shown for caudal positioning of the femoral neck load carrier in terms of reduced varus deformity. The incidence of cut out is however unaffected by the position of the load carrier.
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Affiliation(s)
- L Konstantinidis
- Department of Orthopaedics and Traumatology, Albert-Ludwigs-University Freiburg, Germany.
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Ebrahimi H, Rabinovich M, Vuleta V, Zalcman D, Shah S, Dubov A, Roy K, Siddiqui FS, H. Schemitsch E, Bougherara H, Zdero R. Biomechanical properties of an intact, injured, repaired, and healed femur: An experimental and computational study. J Mech Behav Biomed Mater 2012. [DOI: 10.1016/j.jmbbm.2012.09.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Lenz M, Gueorguiev B, Joseph S, van der Pol B, Richards RG, Windolf M, Schwieger K, de Boer P. Angulated locking plate in periprosthetic proximal femur fractures: biomechanical testing of a new prototype plate. Arch Orthop Trauma Surg 2012; 132:1437-44. [PMID: 22707211 DOI: 10.1007/s00402-012-1556-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Indexed: 02/09/2023]
Abstract
INTRODUCTION To improve proximal plate fixation of periprosthetic femur fractures, a prototype locking plate with proximal posterior angulated screw positioning was developed and biomechanically tested. METHODS Twelve fresh frozen, bone mineral density matched human femora, instrumented with cemented hip endoprosthesis were osteotomized simulating a Vancouver B1 fracture. Specimens were fixed proximally with monocortical (LCP) or angulated bicortical (A-LCP) head-locking screws. Biomechanical testing comprised quasi-static axial bending and torsion and cyclic axial loading until catastrophic failure with motion tracking. RESULTS Axial bending and torsional stiffness of the A-LCP construct were (1,633 N/mm ± 548 standard deviation (SD); 0.75 Nm/deg ± 0.23 SD) at the beginning and (1,368 N/mm ± 650 SD; 0.67 Nm/deg ± 0.25 SD) after 10,000 cycles compared to the LCP construct (1,402 N/mm ± 272 SD; 0.54 Nm/deg ± 0.19 SD) at the beginning and (1,029 N/mm ± 387 SD; 0.45 Nm/deg ± 0.15) after 10,000 cycles. Relative movements for medial bending and axial translation differed significantly between the constructs after 5,000 cycles (A-LCP 2.09° ± 0.57 SD; LCP 5.02° ± 4.04 SD; p = 0.02; A-LCP 1.25 mm ± 0.33 SD; LCP 2.81 mm ± 2.32 SD; p = 0.02) and after 15,000 cycles (A-LCP 2.96° ± 0.70; LCP 6.52° ± 2.31; p = 0.01; A-LCP 1.68 mm ± 0.32; LCP 3.14 mm ± 0.68; p = 0.01). Cycles to failure (criterion 2 mm axial translation) differed significantly between A-LCP (15,500 ± 2,828 SD) and LCP construct (5,417 ± 7,236 SD), p = 0.03. CONCLUSION Bicortical angulated screw positioning showed less interfragmentary osteotomy movement and improves osteosynthesis in periprosthetic fractures.
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Raschke M, Stange R, Kösters C. Versorgung periprothetischer und periimplantärer Frakturen: Moderne Plattenosteosyntheseverfahren. Chirurg 2012; 83:749-62. [DOI: 10.1007/s00104-011-2244-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Lenz M, Windolf M, Mückley T, Hofmann GO, Wagner M, Richards RG, Schwieger K, Gueorguiev B. The locking attachment plate for proximal fixation of periprosthetic femur fractures--a biomechanical comparison of two techniques. Int Orthop 2012; 36:1915-21. [PMID: 22638607 DOI: 10.1007/s00264-012-1574-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Accepted: 05/03/2012] [Indexed: 10/28/2022]
Abstract
PURPOSE Mechanical properties of a locking attachment plate construct (LAP-LCP), allowing bicortical screw placement laterally to the prosthesis stem, are compared to a cerclage-LCP construct. METHODS Eight right synthetic femora with implanted uncemented hip endoprosthesis were cut distally and fixed with LCP, monocortical locking screws and either LAP (n = 4) or cerclage (n = 4). Cyclic testing was performed with monotonically increasing sinusoidal load until failure. Relative movements at the plate-femur interface were registered by motion tracking. Statistical differences were detected by unpaired t-test and general linear model repeated measures. RESULTS Stiffness of the LAP-LCP was significantly higher at the beginning (875.4 N/mm ± 29.8) and after 5000 cycles (1213.0 N/mm ± 101.1) compared to the cerclage-LCP (644.96 N/mm ± 50.1 and 851.9 N/mm ± 81.9), with p = 0.013. Relative movements for AP-bending (B) and axial translation (T) of the LAP-LCP at the beginning (0.07° ± 0.02, 0.20 mm ± 0.08), after 500 cycles (0.16° ± 0.10, 0.26 mm ± 0.07) and after 5000 cycles (0.26° ± 0.11, 0.31 mm ± 0.07) differed significantly from the cerclage-LCP (beg.: 0.26° ± 0.04, 0.28 mm ± 0.05; 500 cyc: 0.47° ± 0.03, 0.53 mm ± 0.07; 5000 cyc.: 0.63° ± 0.18, 0.79 mm ± 0.13), with B: p = 0.02, T: p = 0.04. Relative movements for medial bending were not significantly different between the two constructs. Cycles to failure (criterion 1 mm axial translation) differed significantly between LAP-LCP (19,519 ± 1,758) and cerclage-LCP (11,265 ± 2,472), with p = 0.035. CONCLUSIONS Biomechanically, the LAP-LCP construct improves proximal fixation of periprosthetic fractures compared to the cerclage-LCP construct.
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Konstantinidis L, Papaioannou C, Hirschmüller A, Pavlidis T, Schröter S, Südkamp NP, Helwig P. Effects of muscle-equivalent forces on the biomechanical behavior of proximal femur fracture models: a pilot study on artificial bones. Proc Inst Mech Eng H 2012; 226:681-5. [DOI: 10.1177/0954411912447011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Introduction: There has been extensive analysis of the influence of muscle forces and their effects on the biomechanical behavior of the proximal femur. Nevertheless, these forces have only been taken into account in a handful of biomechanical studies in the field of traumatology. The aim of this study was to analyze the biomechanical behavior of two typical fracture models of the proximal femur based on muscle-equivalent forces. Method: Plate osteosynthesis was performed on two groups of artificial femora to stabilize either a trochanteric osteotomy ( n = 5) or a femur shaft osteotomy ( n = 5). After fixation axial loading was applied to the constructs first without muscle-equivalent forces and then with the addition of these forces (abductor groups and vastus lateralis). Displacement at the osteotomy site and the stiffness of the whole construct were measured during loading. Results: Comparison of the two loading modes revealed no significant differences for displacement or stiffness for the trochanteric fractures. For the femur shaft fractures, a significant difference was found for displacement ( p = 0.023) and stiffness ( p = 0.003) with or without muscle-equivalent forces. Conclusion: The loading protocol for implant testing on femur shaft fractures should include muscle-equivalent forces. For trochanteric fractures, consideration of muscle forces is not entirely necessary since they will have little effect on the results, for example, when comparing implants.
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Affiliation(s)
- Lukas Konstantinidis
- Department of Orthopaedics and Traumatology, Albert-Ludwigs-University Freiburg, Germany
| | | | - Anja Hirschmüller
- Department of Orthopaedics and Traumatology, Albert-Ludwigs-University Freiburg, Germany
| | - Theodoros Pavlidis
- Department of Orthopaedics and Traumatology, Albert-Ludwigs-University Freiburg, Germany
| | - Steffen Schröter
- Department of Orthopaedics and Traumatology, Albert-Ludwigs-University Freiburg, Germany
| | - Norbert P Südkamp
- Department of Orthopaedics and Traumatology, Albert-Ludwigs-University Freiburg, Germany
| | - Peter Helwig
- Department of Orthopaedics and Traumatology, Albert-Ludwigs-University Freiburg, Germany
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Konstantinidis L, Helwig P, Seifert J, Hirschmüller A, Liodakis E, Südkamp NP, Oberst M. Internal fixation of dorsally comminuted fractures of the distal part of the radius: a biomechanical analysis of volar plate and intramedullary nail fracture stability. Arch Orthop Trauma Surg 2011; 131:1529-37. [PMID: 21744234 DOI: 10.1007/s00402-011-1346-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2010] [Indexed: 11/29/2022]
Abstract
INTRODUCTION The purpose of the present study was to carry out biomechanical testing of "new generation" volar plates and an intramedullary nail. METHODS Four volar locking plates (Column Plate, VariAx distal radius, 2.4 mm-LCP and 3.5 mm-LCP) and the intramedullary nail, Targon-DR, were implanted in biomechanically validated artificial bones after simulation of a wedge osteotomy with total transection of the volar cortex to mimic a type 23 A3-fracture according to the AO-classification. Axial load (250 Newton [N]) and volar and dorsal bending loads (both 50 N) were applied. Axial load was increased to fixation failure. Gap motion was measured three-dimensionally directly at the fracture gap. The 3.5 mm-LCP was used for comparison as it currently represents an established locking implant that has been well tested biomechanically. RESULTS In this experimental setting, the 2.4 mm-LCP showed the lowest resistance under all three loading modi and, consequently, the highest level of motion at the osteotomy gap in comparison to all other implants (p < 0.05). Under axial loading, there were no significant differences between the other four implants. Under dorsal bending, the Targon-DR-nail and the VariAx-plate showed less gap displacement in comparison to the 3.5 mm-LCP (p < 0.05). Under volar bending, only the Targon-nail showed greater resistance than the 3.5 mm-LCP (p < 0.05) with no other significant differences between the Column Plate, the VariAx and the 3.5 mm-LCP. CONCLUSION In this experimental setting, all "new generation" implants for distal radius fractures with the exception of the 2.4 mm-LCP showed identical or higher stability compared to the 3.5 mm-LCP. The 2.4 mm-LCP showed the lowest resistance and this must be taken into consideration when planning postoperative functional therapy.
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Affiliation(s)
- Lukas Konstantinidis
- Department of Orthopaedic and Trauma Surgery, Albert-Ludwigs-University Freiburg, Hugstetter Str. 55, 79106 Freiburg, Germany.
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Shah S, Kim SYR, Dubov A, Schemitsch EH, Bougherara H, Zdero R. The biomechanics of plate fixation of periprosthetic femoral fractures near the tip of a total hip implant: cables, screws, or both? Proc Inst Mech Eng H 2011; 225:845-56. [DOI: 10.1177/0954411911413060] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Femoral shaft fractures after total hip arthroplasty (THA) remain a serious problem, since there is no optimal surgical repair method. Virtually all studies that examined surgical repair methods have done so clinically or experimentally. The present study assessed injury patterns computationally by developing three-dimensional (3D) finite element (FE) models that were validated experimentally. The investigation evaluated three different constructs for the fixation of Vancouver B1 periprosthetic femoral shaft fractures following THA. Experimentally, three bone plate repair methods were applied to a synthetic femur with a 5 mm fracture gap near the tip of a total hip implant. Repair methods were identical distal to the fracture gap, but used cables only (construct A), screws only (construct B), or cables plus screws (construct C) proximal to the fracture gap. Specimens were oriented in 15° adduction to simulate the single-legged stance phase of walking, subjected to 1000 N of axial force, and instrumented with strain gauges. Computationally, a linearly elastic and isotropic 3D FE model was developed to mimic experiments. Results showed excellent agreement between experimental and FE strains, yielding a Pearson linearity coefficient, R2, of 0.92 and a slope for the line of best data fit of 1.06. FE-computed axial stiffnesses were 768 N/mm (construct A), 1023 N/mm (construct B), and 1102 N/mm (construct C). FE surfaces stress maps for cortical bone showed Von Mises stresses, excluding peaks, of 0–8 MPa (construct A), 0–15 MPa (construct B), and 0–20 MPa (construct C). Cables absorbed the majority of load, followed by the plates and then the screws. Construct A yielded peak stress at one of the empty holes in the plate. Constructs B and C had similar bone stress patterns, and can achieve optimal fixation.
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Affiliation(s)
- S Shah
- Martin Orthopaedic Biomechanics Laboratory, St Michael’s Hospital, Toronto, Canada
- Department of Mechanical and Industrial Engineering, Ryerson University, Toronto, Canada
| | - S Y R Kim
- Department of Mechanical and Industrial Engineering, Ryerson University, Toronto, Canada
| | - A Dubov
- Martin Orthopaedic Biomechanics Laboratory, St Michael’s Hospital, Toronto, Canada
| | - E H Schemitsch
- Martin Orthopaedic Biomechanics Laboratory, St Michael’s Hospital, Toronto, Canada
- Faculty of Medicine, University of Toronto, Toronto, Canada
| | - H Bougherara
- Department of Mechanical and Industrial Engineering, Ryerson University, Toronto, Canada
| | - R Zdero
- Martin Orthopaedic Biomechanics Laboratory, St Michael’s Hospital, Toronto, Canada
- Department of Mechanical and Industrial Engineering, Ryerson University, Toronto, Canada
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