Does Ultrasound Guidance Improve Effectiveness for Intra-Articular TMJ Steroid Injections in Juvenile Idiopathic Arthritis?

Juvenile Idiopathic Arthritis (JIA) is the most common childhood rheumatic disease. JIA frequently affects the temporomandibular joints (TMJs) and, when this occurs, intra-articular steroid injection (IASI) is one option for treatment. IASI is typically performed by an Oral and Maxillofacial Surgeon (OMS) using facial landmarks and joint palpation, but some authors have suggested that superior results can be achieved when the procedure is performed by an Interventional Radiologist (IR) using image guidance¹. The purpose of this study is to compare outcomes of TMJ IASI performed by an OMS without intraoperative imaging versus by an IR using ultrasound guidance in a series of patients with JIA and TMJ synovitis. We hypothesized that there would be no measurable difference in treatment outcomes based on injection technique.

This is a retrospective cohort study of patients with JIA treated at Boston Children’s Hospital from 2000-2015 who had contrast-enhanced MRIs demonstrating TMJ synovitis and received at least one TMJ IASI. Subjects were included in the “OMS group” if the IASI was performed by an OMS using standard anatomic landmarks and palpation. The “IR group” included subjects who had IASI by an IR using ultrasound guidance. The two groups were age and sex matched. All IASIs included percutaneous intubation of the superior joint space with an 18-gauge catheter, lavage with normal saline and injection of 10mg of triamcinolone hexacetonide (0.5mL of 100mg/5mL Aristospan, Sandoz Inc, Princeton, NJ). Outcome variables included change in maximal incisal opening (MIO), patient-reported pain, and change in synovial enhancement ratio (ER) on contrast enhanced MRIs². Paired t-tests were used to assess the outcome measures and independent t-tests were applied to compare the two groups. Statistical significance was set at p<0.05.

Forty-Five patients were included in the study. Twenty-two subjects (72% female) with a mean age of 13.6 ± 1.3 years were in the OMS group, and 23 subjects (69% female) with a mean age of 13.3 ± 1.8 years were included in the IR group. The mean MIOs for the OMS group were 33.0 ± 5.3mm pre-IASI and 40.1 ± 4.9mm post-IASI (p<0.001). For the IR group, the mean pre- and post-IASI MIOs were 34.5 ± 5.2mm and 41.5 ± 4.1mm, respectively (p<0.001). In the OMS group, 14 subjects (64%) reported TMJ pain prior to IASI and 1 (1%) had pain post-IASI (p<0.001). For the IR group, 15 (75%) had pain pre-IASI and 2 (8%) reported pain post-IASI (p<0.001). The pre-IASI mean ER for the OMS group was 3.70 ± 1.83 and decreased to 2.54 ± 1.36 post-IASI (p<0.001). For the IR group, the pre- and post-IASI mean ERs were 3.50 ± 0.95 and 2.54 ± 0.86, respectively (p<0.001). There were no statistically significant differences in any outcome measure between groups (change in MIO p=0.283; post-operative pain p=1.00; change in ER p=0.492).

In conclusion, we found no significant differences in the outcomes of TMJ IASI performed by an OMS using standard technique compared to an IR using ultrasound guidance. We therefore cannot justify the use of a longer anesthetic, exposure to high doses of radiation, and the increased costs associated with performing routine IASI as an IR procedure.

1. Parra B, Chan M, Krishnamurthy G et al, Use and accuracy of US guidance for image-guided injections of the temporomandibular joints in children with arthritis. Pediatr Radiol (2010) 40:1498–1504

2. Peacock ZS, Vakilian P, Caruso P, Resnick CM, Vangel M, Kaban LB. Quantifying synovial enhancement of the pediatric temporomandibular joint. J Oral Maxillofac Surg (Accepted for publication March 14, 2016)