Bone plate-screw constructs for osteosynthesis – recommendations for standardized mechanical torsion and bending tests

2018 ◽  
Vol 63 (6) ◽  
pp. 719-727
Author(s):  
Hendrik Schorler ◽  
Robert Wendlandt ◽  
Christian Jürgens ◽  
Arndt-Peter Schulz ◽  
Christian Kaddick ◽  
...  

Abstract This paper follows up on a recent systematic review of test methods and parameters for biomechanical testing of bone plates and it is the first study that contains recommendations for standardized mechanical testing of bone plate-screw constructs for osteosynthesis. Following the testing philosophy of ASTM F382 and ISO 9585, we have developed standardized quasi-static and dynamic testing methods for straight linear and anatomically shaped plates, including locked type and conventional systems. The test specification comprises torsion and bending tests along the implant axis and therefore modifies and extends the methods proposed by ASTM F382. We present specific test setups in order to determine product-specific characteristics of the mechanical construct, consisting of the bone plate with corresponding screws (such as construct stiffness, yield strength, ultimate strength and fatigue properties) under the condition that it is rigidly fixed to “healthy bone”. We also address specific testing requirements that are important for the purpose of standardization, such as the positioning of the construct for testing or the number of screws in the diaphysis and metaphysis. Finally, we define the outcome parameters and associated failure criteria related to quasi-static and dynamic testing for comparative purposes. This paper does not intend to replace biomechanical testing of those devices under physiological loading conditions.

2017 ◽  
Vol 62 (3) ◽  
Author(s):  
Hendrik Schorler ◽  
Felix Capanni ◽  
Muneer Gaashan ◽  
Robert Wendlandt ◽  
Christian Jürgens ◽  
...  

AbstractBone plates for osteosynthesis are subject to biomechanical testing for safety and regulatory purposes. International standards applicable for those devices are designed for bone plates used in the surgical fixation of the skeletal system but not necessarily for all device variants available. We intend to summarize the test methods and parameters presented in the literature to evaluate bone plates in a clinical environment, especially for modern anatomically shaped implants. We conducted a systematic review on published biomechanical studies for lower and upper extremities (clavicle, humerus, ulna, radius, metacarpal, femur, tibia, fibula, metatarsal). The search process led to the identification of 159 relevant articles containing 330 individual tests, which were analyzed concerning various test criteria including test methods and parameters per bone segment for static and dynamic loading tests, as well as number of cycles, chosen bone model and outcome variables. The biomechanical literature for bone plates is diverse, inconsistent and heterogeneous. Test methods are not commonly applied per bone plate location and test parameters are not uniformly specified and displayed. They vary in particular for bending and torsion tests as well as for the number of loading cycles for dynamic testing. Outcome variables are not commonly applied nor defined. Consequently this paper is the first in a planned chronological series of three to identify the need (this publication), to develop a systematic procedural approach (2. publication) and to apply the process exemplary on a bone plate sample (3. publication).


1969 ◽  
Vol 20 (1) ◽  
pp. 57-60 ◽  
Author(s):  
R. E. Little

SummaryNishihara’s combined bending and torsion out-of-phase fatigue limit data are analysed. The Tresca shear stress failure criterion predicts strengths up to 30 per cent higher than observed. It thus appears that renewed attention should be given to the basic problem of developing reliable combined stress failure criteria. It is suggested that new test methods will be required for this purpose.


1986 ◽  
Vol 23 (4) ◽  
pp. 573-594 ◽  
Author(s):  
P. K. Robertson

The status of in situ testing and its application to foundation engineering are presented and discussed. The in situ test methods are discussed within the framework of three groups: logging, specific, and combined test methods. The major logging test methods discussed are standard penetration test (SPT), cone penetration test (CPT), and the flat plate dilatometer test (DMT). The major specific test methods discussed are the prebored pressuremeter test (PMT), the self-bored pressuremeter test (SBPMT), and the screw plate load test (SPLT). Discussion is also presented on recent tests that combine features of logging tests (using the CPT) and specific tests (e.g. the seismic, the electrical resistivity/dielectric, and the lateral stress sensing cone penetration tests). A brief discussion is also presented on the applicability, as perceived by the author, of existing in situ test methods and the future of in situ testing applied to foundation engineering. Key words: in situ testing, foundation engineering, penetration testing, pressuremeter.


2014 ◽  
Vol 224 ◽  
pp. 3-8 ◽  
Author(s):  
Sebastian Kamiński ◽  
Marcel Szymaniec ◽  
Tadeusz Łagoda

In this work an investigation of internal structure influence on mechanical and fatigue properties of ferritic-pearlitic steels is shown. Ferrite grain size and phase volume fraction of three grades of structural steel with similar chemical composition, but different mechanical properties, were examined. Afterwards, samples of the materials were subjected to cyclic bending tests. The results and conclusions are presented in this paper


2017 ◽  
Vol 870 ◽  
pp. 231-236
Author(s):  
Shu Tsung Hsu ◽  
Yean San Long ◽  
Teng Chun Wu

This work aims to analysis the SEMI PV standards developed in Taiwan during 2009 to 2014. The major technical committee (TC) and task force (TF) include Photovoltaic Technical Committee (2009), Photovoltaic Module Vibration TF (2010), Photovoltaic Cell Vibration TF (2011), Package Performance TF (2012), OPV and DSSC TF (2013), BIPV TF (2013) and Reliability TF (2014). ITRI coordinated these TFs to set up a series of experiments and discussions, which focused on the performance evaluation for PV cell, module and materials. The TFs have developed four standards include SEMI PV23 (2011), SEMI PV38 (2012), SEMI PV56 (2014) and SEMI PV57 (2014). Through these standardizations, some specific test methods and test flows were completed to evaluate the reliability for both c-Si and organic/inorganic PV products, which are helpful to improve the performances of cell and module, and propose the common testing guidelines for PV industry to refer to when desired.


Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1197 ◽  
Author(s):  
Andrzej Kurek

In this study, 16Mo3 steel was analysed for fatigue tests under tension-compression and oscillatory bending conditions. The analysis involved a comparison of fatigue test results obtained using the Manson-Coffin-Basquin, Langer and Kandil models and the models proposed by Kurek-Łagoda. It was observed that it is possible to substitute the basic tension-compression test performed in large testing machines with oscillatory bending tests carried out on a simple, modern test stand. The tests were performed under oscillatory bending on a prototype machine. The testing of 16Mo3 steel proved that the best-known Mason-Coffin-Basquin fatigue characteristic describes the results of all of the experimental tests very well, but the model can only be used when it is possible to divide strains into elastic and plastic components. It should be emphasised here that there is no such possibility in the case of tests performed under oscillatory bending conditions. It was proven that the proposed test method can substitute the tension-compression test very well and be a much more cost efficient way to obtain LCF material fatigue properties.


1991 ◽  
Vol 113 (2) ◽  
pp. 92-101 ◽  
Author(s):  
N. Nir ◽  
T. D. Dudderar ◽  
C. C. Wong ◽  
A. R. Storm

Low cycle fatigue studies of solder joints designed and fabricated to represent generic interconnection structures typical of what might be used in packaging microelectronics have been carried out to assist in the development of a better understanding of the fundamental mechanical properties that determine the reliability of such structures. These studies involve micro scale joints (micro-joints) of both eutectic and 95/5 Pb/Sn solders fabricated by several different processes. In addition to a discussion of the results of recent tests reflecting specified loss-of-strength failure criteria and extensive post-test failure mode analysis of, primarily, 95/5 Pb/Sn micro-joints, descriptions of (1) the design and fabrication of the custom shear test vehicles and (2) the high-resolution electro-mechanical loading system used to apply cyclic loadings under isothermal conditions will be presented. This computer controlled system provides for the application of fully or partially reversed shear strains (with or without dwells) to either prototypes or custom test vehicles, and can be operated to maintain either total or plastic strain control during cycling.


2016 ◽  
Vol 852 ◽  
pp. 1488-1492 ◽  
Author(s):  
Jin Rong Wu ◽  
Qin Yong Ma ◽  
Xiao Hong Dong

The change law for fatigue properties of polyester fiber asphalt concrete was acquired under different asphalt content by three point bending tests. The results indicate that fatigue life of polyester fiber asphalt concrete increases firstly and then declines with asphalt content increasing, which shows an optimum asphalt content,4.8%. The optimal asphalt content of polyester fiber asphalt concrete is bigger than that of common asphalt concrete. The way to improve fatigue performance of asphalt pavement is found through studying on polyester fiber asphalt concrete. All will provide a theoretical basis for structural design of asphalt pavement.


Sign in / Sign up

Export Citation Format

Share Document