Ear
External ear tumors - benign / nonneoplastic
Synovial chondromatosis of temporomandibular joint / external auditory canal
Author: Nat Pernick, M.D.
Last author update: 1 October 2013
Last staff update: 7 October 2022
Copyright: 2002-2023, PathologyOutlines.com, Inc.
PubMed Search: Synovial chondromatosis of temporomandibular joint external auditory canal
Table of Contents
Definition / general | Radiology description | Treatment | Gross description | Microscopic (histologic) description | Differential diagnosisCite this page: Pernick N. Synovial chondromatosis of temporomandibular joint / external auditory canal. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/earsynovialchondromatosis.html. Accessed June 3rd, 2023.
Definition / general
- Also called synovial chondrometaplasia, synovial osteochondromatosis
- Possibly neoplastic process in which multiple cartilaginous nodules form in synovium, some detach and float in joint space
- Temporomandibular joint (TMJ) lesions cause asymptomatic mass of external auditory canal with preauricular swelling and limited joint motion (Arch Otolaryngol Head Neck Surg 1999;125:1394)
Radiology description
- Numerous radiopaque loose bodies within TMJ but without bone destruction
- Confined to joint space, usually easily enucleated
- Rarely extends into parotid gland, temporal bone, cranium, auditory canal
Treatment
- Conservative surgery
Gross description
- Synovium with diffuse polypoid or pedunculated nodules, 1 mm to 3 cm, with smooth to granular external surface
Microscopic (histologic) description
- Nodules of mature cartilage of varying cellularity within synovium and joint space
Differential diagnosis
