Observational Study
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Jan 18, 2017; 8(1): 57-61
Published online Jan 18, 2017. doi: 10.5312/wjo.v8.i1.57
“Meniscal” scar as a landmark for the joint line in revision total knee replacement
Wasim Sardar Khan, Jagmeet Bhamra, Rhodri Williams, Rhidian Morgan-Jones
Wasim Sardar Khan, Jagmeet Bhamra, Rhodri Williams, Rhidian Morgan-Jones, Cardiff and Vale Orthopaedic Centre, Llandough University Hospital, Cardiff and Vale NHS Trust, Cardiff CF5 2LD, United Kingdom
Author contributions: Khan WS participated in the acquisition, analysis, and interpretation of the data, and drafted the initial manuscript; Bhamra J and Williams R participated in the drafting of the initial manuscript; Morgan-Jones R was the guarantor and designed the study; all authors reviewed and revised the article critically for important intellectual content; all authors approved the final submitted version.
Institutional review board statement: The study was reviewed and approved by the Cardiff and Vale Orthopaedic Centre.
Informed consent statement: All patients included in the study provided informed consent prior to undergoing surgery.
Conflict-of-interest statement: None.
Data sharing statement: Technical appendix, statistical code, and dataset available from the corresponding author at Dryad repository.
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/
Correspondence to: Wasim Sardar Khan, Knee Fellow, Cardiff and Vale Orthopaedic Centre, Llandough University Hospital, Cardiff and Vale NHS Trust, Longcross Street, Cardiff CF5 2LD, United Kingdom. wasimkhan@doctors.org.uk
Telephone: +44-79-71190720 Fax: +44-20-85703864
Received: April 23, 2016
Peer-review started: April 24, 2016
First decision: June 6, 2016
Revised: October 17, 2016
Accepted: November 16, 2016
Article in press: November 17, 2016
Published online: January 18, 2017

To determine whether tissue identified at the joint line was actually remnant “meniscal” scar tissue or not.


Nine patients undergoing revision knee surgery following informed consent had meniscal scar tissue sent to the histology department for analyses. All revisions were performed where joint line had been raised or lowered at earlier surgery. Although preoperative radiographic evaluations suggested that the joint line had been altered, intraoperatively there was scar tissue at the level of the recreated joint line. This scar tissue has traditionally been described as meniscal scar, and to identify the origins of this tissue, samples were sent for histological analyses. The tissue samples were stored in formalin, and embedded and sectioned before undergoing histochemical staining. All samples underwent macroscopic and microscopic examination by a histopathologist who was blind to the study aims. The specific features that were examined included tissue organisation, surface and central composition, cellular distribution including histiocytes, nuclear ratio and vasculature. Atypical and malignant features, inflammation and degeneration were specifically looked for. A statistical review of the study was performed by a biomedical statistician.


The histological findings for the nine patients showing the macroscopic and microscopic findings, and the conclusion are outlined in a Table. The histological analyses were reviewed to determine whether the tissue samples were likely to be meniscal scar tissue. The response was yes (2, 22%), no (6, 67%) and maybe (1, 11%) based on the conclusions. The results were “yes” when on macroscopy, firm cream tissue was identified. In these two “yes” samples, microscopic analyses showed organised fibrous tissue with focal degenerative areas with laminated pattern associated with histiocytes peripherally but no inflammation. The “no” samples were assessed macroscopically and microscopically and were deemed to have appearances representing fibrous synovial tissue and features in keeping with degenerate scar tissue or connective tissue. One sample was indeterminate and microscopically contained fibro-collagenous tissue with synovial hyperplasia. It also contained some degenerate hyalinised tissue that may represent cartilage, but the appearances were not specific.


Based on our pilot study, we recommend reliance on a number of markers to identify the joint line as outlined above, and to exercise caution in using the “meniscal” scar.

Keywords: Menical scar, Joint line, Revision surgery, Knee, Histology

Core tip: Our findings suggests that the structure identified as the “meniscal” scar may actually represent scar tissue that forms in the available space of the recreated joint line rather than actually represent the level of the native joint line where the meniscus once attached.