Synovial cysts of the temporomandibular joint: an immunohistochemical characterization and literature review

Temporomandibular joint synovial cysts: A systematic review of the literature and a report of two cases

Temporomandibular joint (TMJ) synovial cysts are rare, unlike peripheric locations like the wrist or the knee. They share similar presentations with ganglion cyst, benign and sometimes malignant lesions. Only histopathological analysis confirms diagnosis in some cases, finding a true cyst lined by synoviocytes containing synovial fluid. They seem to be related to an increased articular pressure following trauma. In this study we present two cases of TMJ synovial cyst and a systematic review of the literature. A total of 32 cases were retrieved from published literature in PubMed, Cochrane Library and ClinicalTrials.gov databases using the search terms 'TMJ synovial cyst', 'temporomandibular synovial cyst', 'jaw joint synovial cyst'. Swelling (91.3%) and pain (78.3%) were the most common symptoms. MRI was the most commonly used imaging modality that was found to be beneficial for diagnosis. In almost all cases the cyst was removed under general anesthesia, allowing histopathological examination. Only two patients still had pain after removal of the cyst. No recurrence was observed .

Bilateral synovial cysts of the temporomandibular joint

Synovial cysts very rarely affect the temporomandibular joint (TMJ). On review of the literature, there are 29 reported cases of unilateral synovial cysts of the TMJ. We present a case of bilateral synovial cysts occurring at the TMJs.

Synovial Cysts in the Temporomandibular Joint: a Case Report and Critical Review of the Literature

Background

Synovial cysts of the temporomandibular joint are rare and treatment is based on consensus from cases reporting unilateral successful outcomes. A patient with a synovial cyst is presented, treated with successful surgical excision of the cyst, but without remission of joint symptoms. Furthermore, the case is supplemented by a critical, literature review.

Methods

This case report deals with a patient with a synovial cyst that presented with temporomandibular joint (TMJ) pain and reduced mouth opening. Magnetic resonance imaging verified a TMJ cyst.

Results

Surgical excision removed the synovial cyst, and the patient was followed-up for 4 years, with no recurrence of the cyst. Despite successful excision of the cyst, the symptoms did not subside, and the patient is still in treatment. The critical, literature review found 23 case reports describing 24 synovial cysts. In addition, 4 cases were included as their synovial cysts were erroneously described as ganglion cysts. In 4 cases, histological diagnosis could not be confirmed, and they were excluded. All cases described treatment by surgical excision without recurrence. The reported median follow-up was 10 months and postoperative TMJ symptoms were rarely examined or described.

Conclusions

The temporomandibular joint symptoms may persist despite successful removal of the synovial cyst. Furthermore, the 4 identified synovial cysts, mislabelled as ganglion cysts, represents almost a quarter of the cases of the reported synovial cysts. Correct labelling and reporting of synovial cysts are still imperative to describe the diverse aspects of treatment outcomes following surgical excision.

Ganglion and Synovial Cyst of the Temporomandibular Joint: A Case Report and Literature Review

Ganglion and synovial cysts of the temporomandibular joint (TMJ) are rare. Although histopathological findings differ, clinical presentation is comparable. This study adds a case report of a ganglion of the TMJ to existing literature and a review of all available case reports on ganglion and synovial cysts of the TMJ. Including our own case report, we reviewed 49 cases of ganglion and synovial cysts of the TMJ. They occurred in a female:male ratio of 3:1, at an median age of 46 years (range, 11-64 years). Patients mainly presented with preauricular swelling and pain. After imaging, the ganglion or synovial cyst was most commonly excised under general anesthesia. No recurrences were described.