Skin nontumor
Other dermatoses
Synovial metaplasia
Last author update: 1 August 2011
Last staff update: 31 August 2020
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PubMed Search: Synovial metaplasia
Table of Contents
Definition / general | Clinical features | Microscopic (histologic) description | Positive stains | Negative stainsCite this page: Hamodat M. Synovial metaplasia. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/skinnontumorsynovialmetaplasia.html. Accessed March 21st, 2023.
Definition / general
- Metaplastic changes resembling synovium in non-joint spaces, usually in patients with prior surgery or traumatic injuries
- Synovial-type membranes may form against surface of suture material, tissue expanders or implants
- Associated with movement, loose areolar tissue that would develop spaces secondary to movement, and relatively smooth gliding surfaces that can resist penetration by fibroblasts (Arch Pathol Lab Med 2002;126:727)
- Membranes resemble joint (“true”) synovial membranes
- May be associated with cyst formation and transepidermal fistulae (Am J Surg Pathol 1987;11:343)
Clinical features
- Resemble suture granulomas
Microscopic (histologic) description
- Resembles hyperplastic synovium
Positive stains
- Vimentin (strong); scattered positivity with alpha-1-antichymotrypsin (alpha-1ACT) and lysozyme
Negative stains
- No basement membrane antigens or elastic fibers
