Effectiveness of lateral pterygoid muscle energy technique in patients with temporomandibular joint dysfunction: a...

Temporomandibular joint (TMJ) dysfunction involves both myogenic and articular disc components, often arising from muscular hyperactivity, and impaired coordination of the lateral pterygoid muscle. Insufficient or unbalanced activation of this muscle can disrupt normal disc-condyle motion, contributing to pain, and functional limitation. While Muscle Energy Techniques (MET) have demonstrated efficacy in managing TMJ dysfunction, their specific application targeting the lateral pterygoid remains underexplored. The present trial investigates this targeted approach to determine its effectiveness in improving TMJ kinematics, and function.

Single Blinded Randomized Controlled Trial including 48 participants with symptomatic, and asymptomatic TMJ dysfunction were randomly allocated to two treatment groups with equal allocation in both groups based upon eligibility criteria. Group A received Lateral Pterygoid MET, along with conventional protocol while Group B received only conventional protocol for two weeks, with five sessions per week. The assessment for Maximal Mouth Opening (MMO), lateral deviation, and jaw function using JFLS-20 was conducted at day 0, day 14, and at day 21 follow-up. Ethical approval for the study was obtained from the Jamia Hamdard Institutional Ethics Committee (JHIEC) under Ethical Approval Number Ref. No. 13/24 (19/12/2024).

Significant within-group improvements in MMO, lateral deviation, and jaw function (p < .001). Between-group differences were significant only for lateral deviation, favoring the experimental group (p < .001, Cohen's f = 0.55, partial η² = 0.23). The effect sizes were large for MMO (f = 0.64, partial η² = 0.29), and negligible for JFLS-20 (f = 0.06, partial η² = 0.004). Post hoc power analyses indicated sufficient power ( >0.95) for detecting between-group effects.

This trial demonstrates the effectiveness of lateral pterygoid MET in improving jaw kinematics, with particularly greater improvements observed in lateral deviation, while the intervention showed limited effects on JFLS-20 and MMO when between-group differences were analyzed. These findings highlight the importance of incorporating lateral pterygoid - specific MET into therapeutic interventions for temporomandibular joint dysfunction.