Funding for this research was provided by:
Japanese Orthopaedic Association (JOA-Subsidized Science Project Research 2014-1)
Text and Data Mining valid from 2018-04-27
Received: 18 August 2017
Accepted: 5 April 2018
First Online: 27 April 2018
Ethics approval and consent to participate
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research regulations, and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.Written informed consent was obtained from all participants, and all study protocols were approved by the institutional review board of the National Institute of Advanced Industrial Science and Technology (2015–564).
: The authors declare that they have no competing interests.
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