2 Royal National Orthopaedic Hospital, Stanmore, HA7 4LP, UK
3 The John Charnley Trust, UK
4 Hospital ABC Santa Fe, Carlos Graef Fernández 154-505, Mexico City, México
Acetabular defects, particularly as a result of protrusion of acetabular components into the hemipelvis, may cause serious complications during revision procedures as a result of iatrogenic injury to surrounding anatomical structures. In these challenging cases, we advocate the utilisation of preoperative three dimensional imaging. MRI and CT- imaging offer superior understanding of the three-dimensional quality of bony defects and the relationship of implants to important anatomical structures. Appropriate preoperative planning may also prevent major complications during the removal of the pre-existing hardware, prior to re-implantation of implants. Potential complications include injury of nerves, blood vessels and other intrapelvic structures.
In our case, a major bony defect of the acetabulum was a result of the protrusion of an implanted reinforcement ring. A preoperative, contrast-enhanced CT scan showed that the urethra was in close proximity to the hook of the reinforcement ring.
The preoperative imaging aided in identifying and understanding the potential complications that could occur intraoperatively. Additionally, it delineated the intact anatomic structures prior to surgery, which could have medico-legal implications.
The importance of preoperative imaging and the existing literature is discussed within this case description.
Keywords: Revision hip, revision knee, imaging, cup revision, 3D reconstruction, arthroplasty.
open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.
* Address correspondence to this author at the ENDO-Klinik Hamburg,
Holsenstraße 9, 22767 Hamburg, Germany; Tel: + 49 40 3197 - 1735;
Fax: + 49 40 3197 - 1953; E-mail: Hans-Christian.Schmitz@endo.de