Received: 18 May 2018
Accepted: 13 September 2018
First Online: 3 October 2018
Ethics approval and consent to participate
: This study was approved by the London - Brighton & Sussex Research Ethics Committee (REC no: 09/H1103/50) and conducted between 2009 and 2014.Informed consent was taken from each patient prior to their planned surgery, with consent forms filed within their hospital patient record.
: Not applicable.
: The authors declare that they have no competing interests.
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