Retrospective Cohort Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Jan 18, 2020; 11(1): 27-35
Published online Jan 18, 2020. doi: 10.5312/wjo.v11.i1.27
Corrections in alpha angle following two different operative approaches for CAM-type femoral acetabular impingement - Ganz surgical hip dislocation vs anterior mini-open
Emanuel C Haug, Wendy M Novicoff, Quanjun Cui
Emanuel C Haug, Wendy M Novicoff, Quanjun Cui, Department of Orthopedic Surgery, University of Virginia School of Medicine, Charlottesville, VA 22908, United States
Author contributions: Haug EC, Cui Q and Novicoff WM all contributed equally to this project; Haug EC and Cui Q contributed to design and literature Research; Novicoff WM contributed to statistical analysis; Cui Q performed surgical procedures; Haug EC and Cui Q wrote the manuscript.
Institutional review board statement: This study was reviewed and approved by the University of Virginia Institution Review Board, ID# 18513.
Informed consent statement: Patients were not required to give informed consent to this study because the analysis used anonymous data that were obtained after each patient agreed to treatment by written consent.
Conflict-of-interest statement: Haug EC and Novicoff WM have no disclosures. Cui Q has received research grants by Exactech and NIH. He is a board member of VOS and ARCO, and editorial board member at the Journal of Arthroplasty and Journal of Orthopaedic Research.
STROBE statement: The authors have read the STROBE Statement-checklist of items, and the manuscript was prepared and revised according to the STROBE Statement-checklist of items.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Quanjun Cui, MD, Professor, Vice Chair for Research, Department of Orthopaedic Surgery, University of Virginia School of Medicine, Charlottesville, VA 22903, United States. qc4q@hscmail.mcc.virginia.edu
Received: March 7, 2019
Peer-review started: March 8, 2019
First decision: April 16, 2019
Revised: May 16, 2019
Accepted: November 6, 2019
Article in press: November 6, 2019
Published online: January 18, 2020
Core Tip

Core tip: It is well understood that femoroacetabular impingement (FAI) is a predisposing factor for secondary osteoarthritis of the hip joint. The two extensively described impingement mechanisms of FAI are CAM and Pincer-type. If conservative management fails, a surgical approach can be chosen. The measurement of the alpha angle is considered a standard method of assessing the severity of pathology in Cam-type FAI on pre-operative plain radiographs. The radiological correction of the alpha angle, as measured on a lateral view radiograph, has not been previously compared between different surgical approaches. This article compares the magnitude of alpha angle correction achieved by using two different operative techniques: the Ganz surgical hip dislocation and the anterior mini-open approach. Seventy-nine patients were identified in a 5-year period who underwent surgery at our institution. Statistically significant decreases in alpha angle were noted for both surgical techniques, with larger decreases seen in the anterior mini-open group.