Synovial chondromatosis (SC) of the temporomandibular joint (TMJ) is a rare disease characterized by the presence of calcified loose bodies within the joint, and few systematically gathered data are available about its epidemiology. The aim of this paper was to describe a case of SC of the TMJ, and to carry out a systematic review of the literature on epidemiology over the past decade. A case of a 53-year-old female with the classical triad of signs and symptoms of SC (pain, swelling, restricted mouth opening) is described. A systematic search in the National Library of Medicine’s PubMed Database was performed. 155 cases were described in 103 publications. Most dealt with single case reports. Females are affected more than males with a 2.5:1 ratio and the mean age of patients was about 46 years. Late diagnosis is common and in most cases more than 2 years elapsed between symptom onset and surgical intervention. Open TMJ surgery is the treatment of choice, since less invasive techniques, such as arthroscopy, allowed complete removal of the loose bodies only in about half of cases. A single recurrence was described, confirming the benign nature of the disease.
Synovial chondromatosis (SC) is a cartilaginous metaplasia of the mesenchymal remnants of the synovial tissue of the joints. Its main characteristic is the formation of cartilaginous nodules that may be pedunculated and/or detach from the synovial membrane, becoming loose bodies within the joint space . The aetiology of SC is not fully understood and cases are divided into primary SC (without identifiable aetiological factors) and secondary SC (with a known aetiology). Secondary cases are often thought to be related to previous trauma, repetitive microtrauma or degenerative arthritis. Primary cases cannot be associated with any supposed aetiological factors and are considered to be more aggressive .
SC usually affects large synovial joints, such as the elbow and knee, and it is uncommon in the temporomandibular joint (TMJ) . The main clinical symptoms are preauricular swelling, pain, limitation of jaw movement and crepitus joint sounds. The diagnosis is made by computerized tomography (CT) and magnetic resonance imaging (MRI) . Surgery is the therapeutic choice to remove nodules and loose bodies from the joint space. Several approaches have been described, depending on the extension of the lesion with respect to the cranial fossa .
The first reported case of SC of the TMJ was in 1933, when Axhausen reported metaplastic chondrogenesis in the synovial membrane . After that, reports were characterized by inconsistencies of nomenclature, until the 1980s when the term ‘SC’ was adopted . A literature review of the period up to 1997 showed that 74 cases of SC of the TMJ were described, mainly as isolated case reports . More recent studies have attempted to summarize the literature data , but none has satisfied the need for a systematic assessment, and the findings are inconsistent regarding the total number of SC cases.
The aim of the present paper is to describe a case of SC of the TMJ and to carry out a systematic review of the literature over the past decade to update the epidemiological data.
A 53-year-old woman was referred because of severely restricted mouth opening and pain in the TMJ area. She presented a slight swelling in the right preauricular area, she was unable to open her mouth more than 20 mm and the midline of the mandible was deflected slightly to the right side ( Fig. 1 ). Symptoms had been present for about 1 year before the appointment and the restriction of mouth opening had worsened progressively. For about 6 months, the patient had worn an oral appliance prescribed by a general dental practitioner on the basis of an unspecified diagnosis of ‘craniomandibular dysfunction’ without experiencing any improvement. After that, the family physician had treated her with anti-inflammatory drugs (ketoprofene 80 mg, twice a day for 7 days) but her symptoms had remain unchanged and she was then referred to the authors’ tertiary centre. During history taking, she denied any past trauma or diagnosis of any rheumatological conditions. Physical examination revealed that, despite the preauricular swelling, neither dysfunction of the facial nerve nor hearing disturbances were present. Joint sounds on the right side were absent and the contralateral joint was negative on palpation. An orthopantomogram seemed to reveal one small calcification around the condyle, so further studies using imaging techniques were requested.
MRI showed an hypoechoic area located anteriorly to the condyle in the closed mouth position and located posteriorly to the condyle in the open mouth position ( Fig. 2 ). CT confirmed the presence of at least two loose bodies within the right TMJ and the diagnostic hypothesis of SC was made. The patient was scheduled for surgery.
A classical surgical approach to the TMJ was chosen owing to the impossibility of removing wide loose bodies by means of arthroscopy alone. Under general anaesthesia, the right TMJ was exposed using a preauricular incision. Immediately after opening the joint capsule, some transparent and viscous fluid came out of the joint space. A large calcified loose body was present in the upper joint space and was removed ( Fig. 3 ), another fibrous micronodular loose body was found around the condyle ( Fig. 4 ). Two large loose bodies were detected within the TMJ, in contrast to the large number of small bodies described in other cases ( Fig. 5 ). Synovectomy was performed to allow clearage of the joint compartment from any potential residual of metaplastic activity. Post-surgical histological examination revealed chondrometaplasia of the synovial membrane and confirmed the diagnosis of SC of the right TMJ, classified as third stage according to Milgram’s classification ( Fig. 6 ) .
The postoperative course was uneventful and only painkillers and antibiotics were prescribed. The day after surgery, a postoperative mouth opening of 28 mm was recorded, with no motor deficit on the right side of the face. Vigorous physiotherapy was started 1 week before surgery, and follow-up assessments were scheduled at 1 week, 1 month, 3 months, 6 months and 1 year. At the 1 year appointment, a maximum mouth opening of 43 mm was recorded, with no signs of recurrence ( Fig. 7 ).
On 30 July 2009 a systematic search in the National Library of Medicine’s PubMed Database was performed to identify all peer-review papers in the English literature dealing with cases of SC of the TMJ. The studies included for discussion in the review were clinical studies describing surgical interventions performed on one or more new cases of SC of the TMJ with respect to the last comprehensive review carried out by V on lindern et al. .
The search strategy comprised four steps: a search based on the Medical Subjects Headings (MeSH) of the PubMed database; a word terms search within the PubMed database; a search within PubMed related articles to find the selected ones; a search within the references lists of the selected articles.
The following MeSH terms were used to identify a list of potential papers to be included in the review.
TMJ: an articulation between the condyle of the mandible and the articular tubercle of the temporal bone. Year introduced: 1997.
SC: rare, benign, chronic, progressive metaplasia in which cartilage is formed in the synovial membranes of joints, tendons sheaths, or bursae. Some of the metaplastic foci can become detached producing loose bodies. When the loose bodies undergo secondary calcification, the condition is called synovial osteochondromatosis. Year introduced: 1990 (previous indexing: chondroma, 1966–1989).
The search was limited to papers in the English language published later than 01/01/1998 and the combination of the two MeSh terms allowed the identification of 23 citations, the abstracts of which were read to select articles to be retrieved in full text. After abstract reading, 12 papers were selected for inclusion in the review.
In the second step of the literature search the combined word terms ‘TMJ’ and ‘SC’ were used to identify other potential papers to be included in the review. Limits were set as described above. This search strategy provided a list of 49 new citations, the abstracts of which were read to select articles to be retrieved in full text. After abstract reading, 30 additional papers were selected for inclusion in the review.
A search within the PubMed related articles for each of the included papers and a hand-made search within the references lists of the included papers were performed, but no additional relevant papers were identified.
A total of 42 papers were selected for inclusion and discussion in this review on the basis of abstract reading. Retrieval of full texts was possible for 38 papers, while in four cases the full text of the paper was not retrieved because the authors were unavailable because of address changes or did not respond to the authors’ request.
For each of the included studies, the following data were recorded for discussion: sample size; age of the patient at the time of surgical intervention; male-to-female ratio; right-to-left joint ratio; clinical signs and symptoms; duration of symptoms before intervention; diagnostic imaging technique; type of surgical technique; number of loose bodies extracted from the joint space; follow-up period at the time of last observation after intervention; presence/absence of recurrence ( Table 1 ). Papers available only in abstract form were included in the table to provide as much comprehensive data as possible on the prevalence and demographic features of the disease; most of them provided sufficient information but little information on the other features of the cases was available, and is thus missing from the table.
|Study’s first author and year||Sample size||Age||F/M ratio||R/L joint||Clinical signs and symptoms||Duration of signs and symptoms||Diagnostic imaging technique||Surgical technique||Nr. of loose bodies||Follow-up span (months)||Recurrence|
|Cai , 2009||1||21||1 F||1 L||Pain, reduced MIO, click, concurrent pigmented villonodular sinovitis||N.S.||MR||Arthroscopy||Multiple (unspecified)||13||No|
|Peng , 2009||1||58||1 F||1 R + L||Slight diffuse swelling, reduced MIO, preauricular tenderness||N.S.||OPT, CT||Open surgery with diskectomy||Multiple (unspecified)||N.S.||N.S.|
|Zha , 2009||1||44||1 M||1 L||Crepitation, deflection, hard 3.5 cm mass in the preauricular area||3 years||CT, MR||Open surgery with no diskectomy or condylectomy||Multiple (90–95)||60||No|
|Adachi , 2008||1||25||1 F||1 L||Trismus, TMJ pain exacerbated with function||9 months||N.S.||Arthrocentesis||Multiple (unspecified)||N.S.||N.S.|
|Fernandez-sanroman , 2008||5||34–56||3 F, 2 M||3 R, 2 L||Pain (5/5 cases), occlusal changes (4/5), swelling (3/5), dysfunction (3/5)||34–48 months||OPT, MR, CT||Arthroscopy (3) or open surgery (2)||Multiple (unspecified)||16–108||No|
|Hohlweg-majert , 2008||5||12–66||4 F, 1 M||1 R, 4 L||Preauricular swelling and pain in 4/5 cases, only pain in 1 case||1–36 months||OPT (1) MR (4) CT (3) CBCT (2)||Computer-assisted surgery||Multiple (unspecified)||0–132||No|
|Honda , 2008||1||35||1 F||1 R||TMJ pain and reduced MIO||10 years||MR, AR, CBCT||Arthroscopy (only with partial removal of loose bodies)||Multiple (15)||12||No|
|Kademani , 2008||1||55||1 F||1 R||Preauricular swelling, open bite on the affected side, headache||N.S.||OPT, CT||Open surgery with condyloplasty e glenoid fossa repair||Multiple (unspecified)||N.S.||N.S.|
|Sembronio , 2008||1||28||1 F||1 R||Pain and swelling||N.S.||MR||Arthroscopy plus open surgery to allow removal of all loose bodies||Multiple (unspecified)||N.S.||N.S.|
|Yokota , 2008||1||52||1 M||1 R||Pain, swelling, difficulties to open the mouth||N.S||CT, MR||Combined transzygomatic temporal skull base and perauricular approach (condylectomy and cranial fossa repair)||Multiple (unspecified)||N.S.||No|
|Acar , 2007 * ,||1||72||–||–||–||–||–||–||–||–||–|
|Balliu , 2007||1||31||1 M||1 R||Painful swelling||N.S.||CT, MR||Open surgery||Single mass (cartilagineous nodules surrounded by synovia)||0||No|
|D’souza , 2007||1||63||1 F||1 L||Pain, swelling, crepitus, history of past unresolutive interventions||10 years||CT||2 Open surgeries, the second with synovectomy, diskectomy and interposition of dermis-fat graft (programmed for a condylar resection)||Multiple (unspecified)||∼72||Yes|
|Lieger , 2007||1||42||1 F||1 R||Pain on function, slight deflection on mouth opening||5 years||OPT, MR, CT||Open surgery with synovectomy||Multiple (unspecified)||9||No|
|Mandrioli , 2007 * ,||1||–||–||–||–||–||–||–||–||–||–|
|Reyes macias , 2007||1||54||1 F||1 R||Pain on jaw movement, deformity of the TMJ||5 years||N.S.||Open surgery||Multiple (unspecified)||8||No (infiltration with steroids to control pain after 1 month)|
|Xu , 2007||1||49||1 F||1 L||Pain, headache, swelling||7 years||MR, CT||Open surgery||Multiple (unspecified)||24||No|
|Hammodeh , 2006 * ,||1||–||–||–||–||–||–||–||–||–||–|
|Huh , 2006||1||74||1 M||1 L||Swelling with intermittent pain||2 years||OPT, CT, MR||Open surgery with high condylectomy||Multiple (unspecified)||N.S.||N.S.|
|Ardekian , 2005||11||19–72||8 F, 3 M||6 R, 5 L||TMJ pain (10/11 cases), swelling (8/11), reduced MIO (3/11)||1–180 months||OPT, CT, MR||Open surgery with synovectomy (11/11) and diskectomy (7/11) with temporalis flap (6/11)||Multiple in 7/11 cases, no in 4/11 (diagnosis confirmed by histologic examination)||12–120||No (one case of ortho surgery needed to correct occlusion after SC)|
|Hamilton , 2005||1||66||1 F||1 L||Asymptomatic preauricular mass||2 years||CT, MR||Unsuccessful aspiration followed by open surgery||Multiple (unspecified)||N.S.||N.S.|
|Martin-granizo , 2005||1||49||1 F||1 L||Pain, swelling, joint sounds||6 months||CT, MR||Open surgery after unsuccessful arthroscopy||Multiple (over 200)||12||No|
|Mupparapu , 2005||1||65||1 F||1 R||Premature dental contact in the left and open bite in the right side||18 months||CT, MR||Open surgery with steel plate to repair cranial perforation||Multiple (unspecified)||3||No|
|Sarlani , 2004||1||35||1 F||1 L||Limited MIO, asymmetry of the TMJ||7 years||MR||Open surgery with partial parotidectomy||Multiple (109)||6||No|
|Holmlund , 2003||9||24–81||7 F, 2 M||6 R, 3 L||TMJ pain and impaired mandibular function||8–72 months||OPT (9/9 cases), MR (4/9), CT (3/9), AR (1/9)||Open surgery||Multiple (3–80)||12–194||No|
|Ishii , 2003||1||38||1 F||1 L||Pain, swelling, reduced MIO||3 years||CT||Open surgery, calcification of the lateral pterygoid muscle left in place to avoid excessive bleeding||Multiple (unspecified)||120||No|
|Rootkin-gray , 2003||1||56||1 M||1 R||Pain, swelling, trismus||N.S.||ST||Open surgery||Multiple (110)||18||No|
|Shibuya , 2003||1||51||1 F||1 R||Pain, reduced MIO||N.S.||ST||Open surgery with diskectomy||Multiple (unspecified)||24||No|
|Aydin , 2002||1||39||1 M||1 L||Intermittent pain, mass over the zygomatic arch||3 years||CT, MR||Open surgery with disk repositioning||Multiple (unspecified)||24||No|
|Shibuya , 2002||1||57||1 F||1 R||Pain, reduced MIO, mandibular deflection to the affected side during movement||2 years||MR, AR||Arthroscopy||Multiple (unspecified)||10||No|
|Von lindern , 2002||8||26–71||5 F, 3 M||4 R, 4 L||Typical symptoms not present in all cases||N.S.||CT, MR||Open surgery with synovectomy and diskectomy||Multiple (unspecified)||N.S.||N.S.|
|Gay-escoda , 2001||1||42||1 M||1 L||Pain that increate with movements||3 years||CT||Open surgery with partial synovectomy and remodeling condylectomy||Multiple (4)||60||No|
|Koyama , 2001||2||47||2 F||2 L||Pain, mandibular deviation toward the other side at rest||N.S.||CT||Open surgery with diskectomy||Multiple (up to 95)||N.S.||N.S.|
|Yildiz , 2001||1||39||1 M||1 L||Facial asymmetry, mobile perauricular mass||4 years||MR, CT||Open surgery||Multiple (unspecified)||N.S.||N.S.|
|Miyamoto , 2000||2||21–37||2 F||2 R||Pain, reduced MIO, deflection on the affected side during mouth opening||15–120 months||MR (1 case), CT (1 case)||Arthroscopy (1 case) or open surgery (1 case)||Multiple (2–20)||10–15||No|
|Petito , 2000||4||31–63||4 F||3 R 1 L||Pain, limited MIO, swelling||1–24 months||CT (2/4 cases), MR (1/4), AR (1/4)||Open surgery||Multiple (unspecified)||0–36||No|
|Reddy , 2000||1||64||1 M||1 L||Infratemporal swelling||N.S.||CT, MR||Open surgery with cranial fossa repair||Multiple (unspecified)||N.S.||No|
|Shibuya , 2000 * ,||1||–||–||–||–||–||–||–||–||–||–|
|Ercoli , 1998||1||54||1 F||1 R||Pain, swelling, occlusal changes, joint sounds||N.S.||OPT, CT, MR||N.S.||Multiple (unspecified)||3||No|
|Gil-salù , 1998||1||65||1 F||1 L||Sensory disturbances, pain, peripheral facial nerve palsy||8 years||CT, MR||Open surgery with skull base repair||Single giant mass||15||No|
|Karlis , 1998||1||45||1 F||1 R||Pain, swelling, history of multiple trauma||N.S.||CT||Open surgery||Multiple (unspecified)||N.S.||N.S.|
|Louis , 1998||1||32||1 F||1 R||‘Fullness’ in the preauricular area||6 months||CT, MR||Unsuccessful arthroscopy followed by open surgery||Multiple (15–20)||24||No|