Journal of Orthopaedic Surgery and Research This Provisional PDF corresponds to the article as it appeared upon acceptance Fully formatted PDF and full text (HTML) versions will be made available soon Open wedge high tibial osteotomy: cause of patellar descent Journal of Orthopaedic Surgery and Research 2012, 7:3 doi:10.1186/1749-799X-7-3 Jason CH Fan (fchjason@netvigator.com) ISSN Article type 1749-799X Technical Note Submission date March 2011 Acceptance date 12 January 2012 Publication date 12 January 2012 Article URL http://www.josr-online.com/content/7/1/3 This peer-reviewed article was published immediately upon acceptance It can be downloaded, printed and distributed freely for any purposes (see copyright notice below) Articles in Journal of Orthopaedic Surgery and Research are listed in PubMed and archived at PubMed Central For information about publishing your research in Journal of Orthopaedic Surgery and Research or any BioMed Central journal, go to http://www.josr-online.com/authors/instructions/ For information about other BioMed Central publications go to http://www.biomedcentral.com/ © 2012 Fan ; licensee BioMed Central Ltd This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited Open wedge high tibial osteotomy: cause of patellar descent Jason CH Fan Department of Orthopaedics & Traumatology, Alice Ho Miu Ling Nethersole Hospital, Hong Kong SAR, People's Republic of China Correspondence: fchjason@netvigator.com Abstract: This was a retrospective review of the nine open wedge high tibial osteotomy (HTO) done in a regional hospital in Hong Kong from 2006 to 2008 The mechanical hip-knee-ankle angle improved from average 169.5°(164°-175°) to average 183.9° (179°–187°) Patellar descent was noted in all patients postoperatively, with Blackburne-Peel (BP) index significantly changing from 0.78 (0.64-0.93) to 0.59 (0.38-0.78) (p