Abstract
Mixed connective tissue disease (MCTD) is a rare systemic autoimmune disorder, which can affect the temporomandibular joint (TMJ). The literature on TMJ dysfunction in patients with MCTD is however sparse. This is a case report of a 35-year old woman with MCTD, who presented with severe pain from the temporomandibular region. She had a disc-derangement and intra-articular erosions of her left TMJ and developed a fibrous ankylosis of her right TMJ. The conditions led to arthroplasty with interposition of a temporalis muscle flap (TMF) bilaterally. Follow-up showed re-establishment of the cortical borders of the condyles and glenoid fossae and a pain free craniomandibular articulation within a normal range of motion. This is to our knowledge the first report on TMJ ankylosis and arthroplasty with the interposition of TMFs in a patient with MCTD. The report describes the clinical progression, the surgical intervention and presents a narrative review of the literature.
Highlights
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MCTD is a rare autoimmune disease which can affect the TMJs.
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Patients with MCTD can develop TMJ ankylosis.
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The temporal muscle flap can serve as a stable TMJ interposition graft in MCTD.
1
Introduction
MCTD is a rare systemic autoimmune disorder, defined by the presence of serum antibodies targeting the U1 small nuclear ribonucleoprotein (U1snRNP) and overlapping clinical features of Systemic Lupus Erythematosus (SLE), Systemic Sclerosis (SSc) and Polymyositis/Dermatomyositis (PM/DM) [ , ]. Clinical features include Raynaud’s phenomenon, polyarthralgia/polyarthritis, myositis, sclerodactyly, oesophageal hypomobility, interstitial lung disease (ILD) and pulmonary arterial hypertension (PAH) [ ].
The estimated mean annual incidence of MCTD is about 2.1 per million per year [ ]. 7–23% of the total MCTD population have a juvenile (<18 years) onset (JMCTD) [ , ]. Polyarthritis is a common symptom, mainly limited to the hands and feet [ ]. Joint erosions tend to develop 10–15 years after the onset of JMCTD/MCTD [ , ], and are present in about half of the JMCTD/MCTD population [ , ]. It is suggested that MCTD with erosive arthritis is a separate phenotype, less often presenting with ILD or PAH [ ]. The extent of joint damage in general remains unclear [ ] and very little is known about TMJ involvement, though there seems to be a higher prevalence of TMJ symptoms and severe TMJ erosions in patients with MCTD compared to healthy controls [ ].
The basic immune-modulating treatment in MCTD is hydroxychloroqiune (HCQ). Corticosteroids (CS), methotrexate (MTX), cyclosporine, azathioprine and mycophenolate mofetil (MMF) are used in addition when treating MCTD-related arthritis. There are some reports on therapy-resistant arthritis successfully treated with rituximab, and indications that TNF-α inhibitors could be used treating severe MCTD-arthritis [ ].
This report presents a rare case of MCTD with severe TMJ degeneration and fibrous ankylosis, treated with bilateral arthroplasty with the interposition of TMFs.
2
Case report
The patient, a 35-five-year-old female, had an onset of general arthralgia at the age of seven and was diagnosed with MCTD at sixteen. TMJ pain developed in her late twenties. Initial TMJ-treatment included jaw exercises, occlusal splint therapy and intra-articular CS injections (IACS) by a specialist in stomathognathic physiology. As her symptoms got worse, she was referred to our department for arthrocentesis. The medical treatment was directed by her rheumatologist, and included HCQ, ibuprofen, amitriptyline, pregabalin, mepenzolate, omeprazole and also recurrent IACS in the hands and feet. For reasons unknown, one had chosen not to use MTX or MMF, nor try rituximab or TNF-α inhibitors.
At refrerral the patient reported on a constant pain from the temporomandibular region at rest, 8 on a visual analogue scale (VAS), and intense pain when moving the jaw (VAS 10). Clinical examination demonstrated a maximal interincisal opening (MIO) of 20mm, with severe pain from the TMJs and the masticatory muscles. Bilateral arthrocentesis was performed twice within a period of two months. There was a slight increase of the MIO, a decrease in pain in the right TMJ, but persisting pain in the left TMJ.
Magnetic resonance imaging (MRI) showed a perforated, oedematous and anteromedial displaced disc of the left TMJ. On the right side the disc was intact and non-dislocated, and a small condylar subcortical cyst was present. Computed tomography (CT) revealed erosions of the articular surfaces of the eminence and glenoid fossa in the left TMJ. Both condylar heads had well-defined cortical borders. A radiopaque structure was noted in the soft tissue inferior to the articular eminence on the right side ( Fig. 1 ).
The symptoms, clinical and radiographic findings indicated removal of the left articular disc. Due to the erosive lesions, interposition of a TMF was advocated to prevent postoperative ankylosis.
2.1
Surgery of the left TMJ
Surgery was performed under general anaesthesia. The left TMJ was exposed through an extended pre-auricular incision. The articular disc was perforated and adherent to the articular eminence, with degenerative lesions of the articular cartilage. Inflamed synovial membrane and the articular disc were removed. The eminence and the condylar head were reduced and the bony surfaces smoothened. A thin pedicled TMF was raised and folded over the zygomatic arch. The flap was interposed in the joint space and fastened with resorbable sutures. The tissues were thereafter closed in layers.
Gentle jaw movements were allowed postoperatively, and jaw exercises were initiated after two weeks.
2.2
Follow up
After seven months the MIO was 36mm. The left TMJ presented with minimal pain, but the right TMJ was distinctly painful. A new CT-scan revealed erosions of the right condylar head and the glenoid fossa, and also intra- and extracapsular bone formation. The left TMJ presented with new bone formation within the glenoid fossa, and a reduction of the condyle and eminence in accordance with previous surgery ( Fig. 2 ).
