Abstract
Background
Chondrocalcinosis is a metabolic disorder characterized by non-infectious joint inflammation with intra- or periarticular calcification. Temporomandibular (TMJ) chondrocalcinosis is rare and not usually included in the differential diagnosis of TMJ and facial pain disorders.
Case report
A 67-year-old woman presented with a calcified mass in the right TMJ between the condyle and glenoid fossa, eroding into the floor of the middle cranial fossa due to calcium pyrophosphate deposition in the TMJ. She underwent surgical excision of the mass with immediate econstruction with a custom-made prosthesis. On follow-up, there was complete clinical resolution, with no evidence of recurrence. Literature related to surgical treatment of chondrocalcinosis of TMJ and its treatment was reviewed. Surgery is the most commonly used treatment. A custom-made device allowed us to bridge the defect caused by the destructive disease process.
Conclusion
Custom-made prostheses can be considered a safe and effective solution in erosive forms of chondrocalcinosis, replacing the TMJ to restore functionality and correct the anatomical defect.
Highlights
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Chondrocalcinosis is a metabolic disorder characterized by non-infectious joint inflammation with periarticular calcification.
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Erosive TMJ chondrocalcinosis can present with a calcified mass eroding into the floor of the middle cranial fossa.
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Surgical excision of the mass and immediate reconstruction with a custom-made prosthesis is the optimal choice.
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Custom-made prostheses are an effective solution in erosive forms of chondrocalcinosis to restore TMJ function.
1
Background
Chondrocalcinosis is a rare disease that has been reported infrequently, characterized by noninfectious joint inflammation with intra- or periarticular calcification, caused by calcium pyrophosphate dihydrate (CPPD) crystal deposition. “Pyrophosphate arthropathy” is an alternative term used to describe the structural damage to the joint caused by deposition of CPPD crystals simulating degenerative joint disease; “pseudogout” refers to intermittent acute attacks of arthritis [ ]; “tophaceous pseudogout” characterizes lesions that have massive or tumoural CPPD crystal deposition and is one of the rarest forms of CPPD deposition disease, however, it should be mentioned because of its clinical and radiological resemblance to cartilaginous tumors [ ]. Pathogenesis is not clear. Synovial fluid levels of inorganic pyrophosphate (PPi) are higher than plasma levels in these patients, and this gap might indicate a local origin of PPi. Chondrocytes are believed to overproduce PPi since microscopic cartilage examination reveals the initial presence of crystals at the lacunar margin of these cells. Various conditions have been associated with CPPD crystal deposition disease such as hemochromatosis, hemosiderosis, familiar hypocalciuric hypercalcemia, hyperparathyroidism, hypothyroidism, hypophosphatasia, hypomagnesemia, diabetes, chronic renal dialysis, gout, aging, amyloidosis, neuropathic joint disease, oral parafunctional habits, trauma and surgery [ ]. Deposition of CPPD crystals is more common in large fibrocartilaginous joints than in hyaline cartilage. It is characterized by linear and punctate radiodensities in fibrocartilaginous structures, such as meniscus or articular fibrocartilage, and most commonly affects the knee meniscus and triangular ligament of the wrist [ ]. Radiological diagnosis is essential, but definitive diagnosis comes from analysis of the crystals: a differential diagnosis from other crystalline-induced arthritis or tumors with calcification in the TMJ must be made. CPPD crystals are rhomboid and display weak positive birefringence and for a definite diagnosis of CPPD arthropathy a demonstration of rhomboidal crystals on polarized light microscopy is required. Temporomandibular (TMJ) chondrocalcinosis was first described in 1976 [ ]. Chondrocalcinosis is not usually included in the differential diagnosis of TMJ and facial pain disorders, unless the diagnosis has been established in other joints. CPPD may mimic other joint affections, such as gout, rheumatoid arthritis, degenerative joint disease, neoplastic or infectious conditions, further delaying the diagnosis [ ]. Common signs and symptoms of TMJ chondrocalcinosis include pain, joint swelling, trismus, limited mouth opening, malocclusion, and hearing loss due to middle hear effusion. These symptoms are very common in many TMJ disorders, including both inflammatory and neoplastic processes [ ]. Since chondrocalcinosis can lead to significant alterations of normal TMJ anatomy, treatment of advanced stages might be challenging. Surgical treatment is the most commonly described approach to TMJ chondrocalcinosis, and many approaches have been described. We report a case of chondrocalcinosis of the TMJ that required an immediate alloplastic total joint replacement in a one-stage surgical approach. A review of the literature related to surgical treatment of chondrocalcinosis is also presented.
2
Case report
A 67-year-old woman with a three-year history of pain in the right preauricular area and progressive reduction of mandibular opening was referred to Maxillofacial Surgery Department (Academic Hospital, University of Udine). On examination, she had no facial swelling or asymmetry, and no tenderness of the masticatory muscles on palpation was appreciated. There was tenderness on the lateral pole of the right TMJ. Mouth opening was limited to 25 mm, causing right TMJ pain. The patient did not complain about any modification of the occlusion, although an expansive lesion of TMJ was present. Moreover, the patient was edentulous in the posterior mandible and even if there were any tendencies to posterior open bite, this was not reported by the patient, nor did it appear at the physical examination. She had no history of other joint disease conditions. Computed tomography (CT) showed a destructive process with a calcified mass in the right TMJ between the condyle and glenoid fossa with erosion into the floor of the middle cranial fossa and extending laterally and medially into the infratemporal fossa ( Fig. 1 ). Virtual surgical planning of the resection was based on the preoperative CT images ( Fig. 2 ). Resection was simulated, enabling finalization of the design of the joint prosthesis. Preauricular and retro-submandibular approach were performed to gain access to the angle and ramus of the mandible. The entire joint space appeared to be filled with granulomatous tissues eroding the glenoid fossa and disrupting the TMJ capsule. The mass was resected and extensive debridement was performed. Condylectomy was performed before removing the tumor, to provide a wider access to the medial compartment of the joint. Moreover, coronoidectomy was also performed based on the following assumptions: 1) the lesion extended up to the infratemporal fossa and, although it was not a malignant neoplasm, coronoidectomy was necessary to completely remove it; 2) since a long time, the patient reported a reduced mouth opening: for this reason, we performed coronoidectomy to provide a further improvement of mouth opening. Remarkably, coronoidectomy is commonly accomplished in the treatment of ankyloses, where there is a shortening of temporalis muscle fibers owing to the chronic reduction of mouth opening. The custom-made prosthesis (SINTAC Biomedical Engineering, Trento, Italy) was then inserted. This device consists of a titanium mandibular implant and a polyethylene fossa; titanium screws were used to attach both the condylar and fossa implants to the bone ( Fig. 3 ). A histopathological examination of the specimens supported the diagnosis of chondrocalcinosis. The patient recovered without complications and was discharged on the third postoperative day. At 1-year follow-up, the patient was free of disease and marked improvement in the subjective and objective clinical parameters was noticed. Joint function had improved to 35-mm interincisal opening and occlusion was maintained. 1-year postoperative CT confirmed complete removal of the lesion, with no signs of relapse (see Fig. 4 ).
