Clinical Outcomes of 297 Children With Juvenile Idiopathic Arthritis and TMJ Disease

Systemic medications and intra-articular injections are the mainstay of juvenile idiopathic arthritis (JIA) treatment. 75-80 % of JIA patients develop temporomandibular joint (TMJ) arthritis. Disease progression in the TMJ will lead to micrognathia/ retrognathia, class II malocclusion, OSA, decrease maximum inter-incisal opening (MIO), ankylosis, chronic pain and poor cosmetic deformities. Micrognathia/ retrognathia are due to condylar resorption and the subsequent loss of vertical mandibular height. The goals of intra-articular injections are to improve mandibular function, slow down disease progression and therefore prevent or minimize complications. This retrospective chart review did not find severe resorption but identified a group of patients that developed heterotopic ossification . A retrospective chart review study for all patients diagnosed with JIA and had intra-articular injections from 2012-2014 was approved by the IRB.  Inclusion criteria: patient’s diagnosed with JIA by pediatric rheumatologist, evidence of TMJ involvement, and at least 1 intra-articular injection. The purpose of the study is to document the treatment outcome of intra-articular injections with different medications; Triamcinolone Hexacetonide (Aristospan) and Infliximab (Remicade). All intra-articular injections were performed without imaging guidance, under general anesthesia and by a single Oral & Maxillofacial Surgeon. The protocol followed is: 2-3 Aristospan (10mg/cc) injections, 6 month apart as indicated by the patient status. Patients unresponsive to Aristospan with severe progressive disease, (pain, limited opening, growth asymmetry, malocclusion or synovitis by MRI were considered refractory; and  2 injections of Remicade (10mg/cc) injections 6 weeks apart. A total of 297 charts were reviewed. 85% had Aristospan, 14% had Aristospan and Remicade while 1 % had Remicade only. Of the 297 patients; 44 patients identified with heterotopic ossification around their condyles. In the heterotopic ossification group (44 patients) 49% had Aristospan and 38% Aristospan and Remicade, 7% had Aristospan, Remicade and Kenalog, 4% had Aristospan and kenalog and 2% had Kenalog and Remicade. Female was more than male (which is probably due to the nature of JIA). Right TMJ was involved more than the Left TMJ (no true explanation). We noticed many patterns of heterotopic ossification, ranged from a bulbous condyle, scattered heterotopic bone surrounding the condyle, thickening in the glenoid fossa and a combination of all. All the heterotopic ossification was intra-articular and particularly in the superior joint space. Although definitive heterotopic ossification is identified, most patients had satisfactory mandibular function with good MIO (30 mm-52 mm), and asymptomatic.  Only 3 patients developed TMJ ankyloses. In conclusion, heterotopic ossification is a rare radiographic finding of intra-articular injection or a natural progression of the disease. To our knowledge there is only 1 article in the literature describing this pattern of ossification in a smaller group.

References:

1. Emma C. te Veldhuis, Alwine H. te Veldhuis, Maarten J. Koudstaal. Treatment management of children with juvenile idiopathic arthritis with temporomandibular joint involvement: a systematic review. Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology, Volume 117, Issue 5, May 2014, Pages 581-589.
2. Sahara Ringold,Mahesh Thapa,Elizabeth A. Shaw, and Carol A. Wallace. Heterotopic Ossification of the Temporomandibular Joint in Juvenile Idiopathic Arthritis. J of Rheumatology 2011;38;1423-1428