Septic Arthritis of the Temporomandibular Joint with Intracranial Extension: A Case Report

Abstract

Septic arthritis of the temporomandibular joint (TMJ) is rare with few cases reported in the literature. We present a case of septic arthritis of the left TMJ in an 18-year-old man who was initially referred as a suspected TMJ dislocation. He had a 3-day history of pain, trismus and malocclusion with left preauricular swelling and became clinically septic with a positive blood culture containing Fusobacterium necrophorum. Computed tomography revealed left TMJ effusion. A later scan showed evidence of a temporal space collection and development of an intracranial extension in the left middle cranial fossa. The patient underwent needle arthrocentesis and drainage, followed by six weeks of antibiotic therapy following advice from neurosurgery and microbiology. Further imaging revealed resolution of the collection. Few cases have been reported of this unusual diagnosis, and this case demonstrates the importance of close multidisciplinary input in forming an accurate diagnosis and managing appropriately.

Introduction

An 18-year-old patient was referred to our unit with a suspected temporomandibular joint (TMJ) dislocation. He presented with a 3-day history of pain localised to the left preauricular region, trismus and malocclusion. This was preceded by odynophagia and a suspected diagnosis of tonsil stones, for which he was taking antibiotics prescribed by his General Physician. He was otherwise fit and well, having moved to the UK recently from Gambia.

Examination revealed a left preauricular swelling which extended buccally (Fig. 1), marked trismus and cervical lymphadenopathy, however no true malocclusion. Initial investigations displayed elevated inflammatory markers, with a raised white cell count and C-reactive protein (CRP), and a subtle widening of the left joint space on Orthopantomogram imaging. An ear, nose and throat review ruled out a tonsillar source. Computed tomography (CT) showed a left TMJ effusion with diffuse masseteric and temporal oedema but no collection (Fig. 2). The patient progressed to exhibit clinical signs of sepsis with pyrexia, rigours and a raised lactate of 6.2 mmol/L. Blood cultures revealed a gram-negative bacteraemia. The patient was taken to theatre where a needle aspiration and washout of the left TMJ was subsequently performed, draining two millilitres of purulent fluid from the joint space. The patient was later found to be positive for sickle cell trait, a diagnosis of which he was unaware and had no known family history.

Fig. 1.

Preauricular swelling on initial presentation. Clinical photograph demonstrates the preauricular swelling evident at initial presentation. This was localised over the left Temporomandibular joint with some buccal extension but no evidence of spread into the temporal region at this point

Fig. 2.

Coronal (a) and Axial (b) images of CT Head taken on admission. Computed tomography (CT) taken at initial presentation and prior to any surgical intervention. Demonstrates a left TMJ effusion with diffuse masseteric oedema (a) and temporal oedema (b), but no collection

Pain and trismus improved post-operatively, however with persistence of swelling and intermittent pyrexia. A second CT scan, taken 48 h after the initial procedure, revealed multi-loculated abscess formation in the temporalis with intracranial extension forming extradural empyema in the left middle cranial fossa (Fig. 3). An urgent neurosurgical review was sought in addition to microbiology advice. No bacterial growth had been cultured from pus samples taken intra-operatively, however blood cultures taken on admission yielded anaerobic gram-negative rods after two days growth; isolating Fusobacterium necrophorum after a total of four days growth. Prior to blood culture and sensitivity results, the patient received empirical antibiotic treatment with intravenous Co-amoxiclav and Metronidazole, based on microbiology advice and local trust guidelines for severe odontogenic infections. Following isolation of F. necrophorum and cerebral abscess diagnosis, Co-amoxiclav was substituted for intravenous Meropenem. The patient also underwent a second surgical procedure for an incision and drainage of the temporal space abscess, via a preauricular incision, during which a significant volume of pus was drained from the infra-temporal space. Inflammatory markers improved following the second surgical procedure, resolving to normal levels by six days post-operatively. A repeat CT scan taken at this point demonstrated an overall improvement, with no requirement for further drainage, and therefore intravenous Ceftriaxone was commenced in place of Meropenem on advice of microbiology.

Fig. 3.

Axial images (a–d) of repeat CT Head, taken 48 h after first surgery. CT Head taken 48 h following needle aspiration and washout of left TMJ. Demonstrates marked progression compared with previous study, showing multi-loculated abscess formation in the left temporalis muscle and masticator space, tracking along the lateral border of the zygomatic arch and to the insertion of the temporalis muscle at the coronoid process of the mandible (a & b). Without bone destruction, there is transosseous intracranial spread of infection into the left middle cranial fossa with formation of an extradural abscess anterior to the temporal pole, measuring up to 1.5 cm in thickness and 3 cm × 2.4 cm in size (c & d)

Magnetic resonance imaging (MRI) revealed normal signals in the brain parenchyma immediately adjacent to the extradural collection. The neurosurgical team recommended conservative management of the epidural abscess with six weeks of antibiotic treatment comprising oral Metronidazole (400 mg) three times daily and intravenous Ceftriaxone (2 g) twice daily. A repeat MRI scan taken on completion of antimicrobial therapy demonstrated improved appearances overall, with some minor residual dural thickening overlying the left temporal pole but no defined collection (Fig. 4).

Fig. 4.

Axial images of MRI scans taken before (a) and after (b) antibiotic treatment. MRI scans taken at diagnosis of intracranial abscess (a) and following 6 weeks of antimicrobial therapy (b). Demonstrates an overall improvement at completion of treatment, with a minor residual dural thickening at the left temporal pole but no evidence of a defined collection and with normal signal in the brain parenchyma

Discussion

Septic arthritis has rarely been reported to involve the temporomandibular joint (TMJ). This case reflected common symptoms reported in such cases; including trismus, joint tenderness and sudden malocclusion [1]. Pathogens are introduced via direct spread of local infection or through hematogenous dissemination from a distant site [2]. In this case, given the history of odynophagia, a pharyngeal source could be considered [3].

Usual causative pathogens isolated in similar cases include Staphylococcus aureus and Neisseria [2], however in this case F. necrophorum, an oropharyngeal commensal, was cultured. This anaerobic gram-negative rod is usually associated with Lemierre’s syndrome [4]. F. necrophorum has also been identified as an emerging causative pathogen in otogenic and paranasal infections [4], in addition to being a bacterium isolated from active sites of NOMA (Cancrum Oris) [5]. Septic arthritis is rarely associated with this microorganism with few cases reported in the literature, of which most are isolated from knee and hip joints [6]. Interestingly, one of these cases occurred three weeks following drainage of a dental abscess, suggesting a possible association [7]. Only one paper discusses the association between F. necrophorum and septic arthritis of the temporomandibular joint specifically, with isolation of the pathogen in four paediatric patients [8].

The intracranial extension of infection has been reported in two previous cases of temporomandibular joint septic arthritis [9, 10]. The close anatomical proximity of the TMJ with the skull base can predispose both locations to contiguous spread of infection. In this particular case, no bone destruction or other clearly distinguishable pathology was identified as being responsible for the transosseous intracranial spread of infection into the left middle cranial fossa. Despite soft tissue inflammation extending into the external auditory canal, the middle ear cavity and petromastoid air cells were clear, ruling this out as a potential route. The most plausible theory in this case suggests the role of transforaminal spread of infection into the middle cranial fossa, with the route likely originating from the infra-temporal space.

Conclusion

Awareness of this rare presentation of septic arthritis involving the temporomandibular joint is essential for timely diagnosis and management of the potentially fatal condition. This case demonstrates the need for early multidisciplinary input to prevent further morbidity.

Author contributions

All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Natalie Turton, David McGoldrick, Kieran Walker, Timothy Martin and Prav Praveen. The first draft of the manuscript was written by Natalie Turton and David McGoldrick, and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial or not-for-profit sectors.

Declarations

Conflict of interest

The authors have no competing interest to declare.

Ethics statement/confirmation of patient’s permission

Ethics approval not applicable. The patient’s permission was obtained.