Does ultrasound guidance during arthrocentesis in women with disc displacement without reduction reduce procedure time and improve outcomes? A randomized clinical trial.

Introduction: The goal of using ultrasound-guided (USG) arthrocentesis is to reduce number of needle insertion attempts, which is hypothesized to reduce procedure time, postoperative pain, and consequently, limitation in range of motion.

Purpose: The objective of this study was to compare the therapeutic and operative efficiency of USG Single-Puncture Arthrocentesis (SPA) Type 2 and SPA Type 2 arthrocentesis without ultrasound guidance in the treatment of temporomandibular joint (TMJ) internal derangement (ID) "disc displacement without reduction (DDWOR)."

Materials and methods: A double-blinded prospective randomized clinical trial (RCT) was conducted from December 2022 to December 2023 at Ain Shams University Hospital. It enrolled females with a mean age of 27.00 ± 3.70 years with DDWOR and failed conservative treatment, excluding those with malocclusion, parafunctional habits, systemic diseases, psychological disorders or requiring special needs. In the study, 40 female patients with DDWOR were randomly divided into a control group (SPA Type 2 arthrocentesis) and an intervention group (USG SPA Type 2 arthrocentesis). Patients were assessed for needle insertion attempts as the primary outcome. procedure time, pain measured using visual analogue scale (VAS), and maximum mouth opening (MMO) were also assessed. Follow-up was conducted at 4, 8, and 12 weeks. Patients with differences in age and gender, malocclusion, parafunctional habits, systemic diseases, or psychological disorders were excluded.

Results: The intervention group had fewer needle insertion attempts (1.6 vs. 2.9) and shorter procedure time (11.75 vs. 16 min, p < 0.001). Pain scores (p = 0.846) and maximum mouth opening (p = 0.341) showed no statistically significant differences after 12 weeks. Data were summarized as mean, SD, median, and IQR, with normality assessed by examining the distribution and using the Shapiro-Wilk test. Non-parametric variables were compared using the Mann-Whitney U test. Linear mixed models were assessed via residual plots, Q-Q plots, Shapiro-Wilk, Breusch-Pagan, and VIF tests. Fixed effects were analyzed with ANOVA or Wald Chi-Square tests, followed by Tukey's post-hoc comparisons. Analyses were conducted using R 4.5.0.

Conclusions: USG SPA Type 2 arthrocentesis demonstrated improved procedural efficiency, evidenced by fewer needle insertion attempts and shorter procedure duration. However, it did not result in statistically significant differences in therapeutic outcomes, including pain reduction or maximum mouth opening (MMO). Further research is warranted to determine whether ultrasound guidance provides additional clinical benefits beyond technical facilitation.