Primary aneurysmal bone cyst of the temporomandibular joint: Multidisciplinary management with a CAD/CAM total joint replacement in a unique patient population

Primary aneurysmal bone cysts involving the mandibular condyle are exceedingly rare and may present unique difficulties with respect to diagnosis, ablation and reconstruction. A 27-year-old male Jehovah's Witness presented to an emergency department following a minor traumatic incident with left-sided facial swelling, paresthesia of the third division of the left trigeminal nerve and trismus. A diagnosis of a central giant cell lesion was rendered from an incisional biopsy of a lesion involving the left mandibular condylar head. The patient was initially treated by curettage and installation of a stock temporomandibular joint prosthesis. Histopathologic and molecular analysis revealed the presence of a primary aneurysmal bone cyst. The patient was lost to follow up and eventually returned with severe trismus secondary to ankylosis between a mass of heterotopic bone circumscribing the left mandibular condylar prosthesis and temporal bone which required pre-operative embolization, resection of the osseous mass and placement of a custom temporomandibular joint prosthesis. Intraoperatively, the coil within internal maxillary artery was encountered. Recurrent foci of aneurysmal bone cyst was noted within the resection specimen which was not evident upon pre-operative imaging. This report highlights the utility of multidisciplinary care and the application of contemporary technologies and procedures in the context of a staged approach to temporomandibular joint reconstruction for the treatment of a rare neoplasm in a unique patient population.