“Meniscal” scar as a landmark for the joint line in revision total knee replacement

Table 1 Histological reports for nine patients showing the macroscopic and microscopic findings, and the conclusion

Patient	Macroscopy	Microscopy	Conclusion	Is the tissue likely to be meniscal scar tissue?
1	Cream tissue	Organised fibrous tissue and synovial surface. No atypical features	Appearances likely represent fibrous synovial tissue	No
2	Yellow and white tissue	Fragments of fibrous tissue partly lined by synovium show focal areas of denuded surface with acellular fibrinoid exudate. No significant inflammation	Features in keeping with degenerate scar tissue	No
3	Firm cream tissue	Fibrous tissue with focal degenerate area. No inflammation seen	Meniscal tissue	Yes
4	Firm cream tissue	Sections showing organised fibrous tissue and laminated pattern associated with foamy histiocytes at the periphery under the synovial surface. In areas the fibrous tissue lack nuclei	Appearances likely represent meniscal remnants with degenerate features	Yes
5	Firm cream tissue	Fragments of connective tissue. No features of atypia, malignancy, or significant inflammation	Connective tissue	No
6	Cream tissue	Fragments of fibrous tissue with overlying synovium. There is a mild inflammatory infiltrate	Features in keeping with fibrous scar tissue	No
7	Firm cream tissue	Sections show fragments of connective tissue. No evidence of atypia or malignancy. No significant inflammation is identified. There is a small collection of blood vessels seen in one edge	Connective/scar tissue	No
8	Cream tissue	Fibro-collagenous tissue with synovial hyperplasia. Some degenerate hyalinised tissue that may represent cartilage, but the appearances are not specific	Features in keeping with non-specific articular tissue	Maybe
9	Yellow and white tissue	Fibrous tissue with no significant inflammation	Degenerate scar tissue	No

The histological analyses were reviewed to determine whether the tissue reported was likely to be meniscal scar tissue.