# Postural and biomechanical insights in disc displacement with reduction

## TL;DR

This study compares posture and muscle characteristics in people with disc displacement and healthy individuals, finding similar posture but lower pain thresholds in the affected group.

## Contribution

The study provides new insights into biomechanical and pain threshold differences in disc displacement with reduction compared to healthy individuals.

## Key findings

- Study group showed lower pressure pain thresholds except in specific muscle regions.
- Biomechanical characteristics of certain muscles differed, such as reduced elasticity in the left semispinalis muscle.
- Global posture and mobility were similar between the study and control groups.

## Abstract

Background: Although the relationship between temporomandibular
disorders and posture has been addressed in many studies, a complete consensus
has not yet been reached. This study aimed to evaluate global posture, cervical,
thoracic and lumbar mobility, and the biomechanical characteristics of muscles in
individuals with disc displacement with reduction. Methods: A total of
70 participants were included in the study, consisting of 37 healthy individuals
in the control group and 33 individuals in the study group. The participants
included in the study were assessed for temporomandibular joint range of motion,
pressure pain threshold in regions related to the temporomandibular disorders
(lateral capsule, masticatory muscles and upper trapezius), global posture and
thoracic and lumbar spine mobility, cervical posture and mobility, and the
biomechanical characteristics (elasticity, stiffness and tone) of the
paravertebral muscles, masticatory muscles and upper trapezius. The assessment
was conducted using a digital caliper, an analog algometer, a spinal mouse, a
universal and modified universal goniometer, and MyotonPRO, respectively.
Results: Cervical and temporomandibular joint range of motion were
similar in both groups. The study group showed lower pressure pain threshold
overall, except in the left upper trapezius and right anterior temporalis. The
biomechanical characteristics (elasticity, stiffness and tone) of the masseter
muscle and paravertebral muscles were also comparable, except for reduced
elasticity in the left semispinalis muscle. Global posture and mobility
(cervical, thoracic and lumbar) were alike in both groups. Conclusions:
This study showed that young adults with disc displacement with reduction largely
have similar global posture, mobility (cervical, thoracic and lumbar) and muscle
biomechanical characteristics (elasticity, stiffness and tone) compared to
healthy individuals. However, their pressure pain threshold, especially at the
joint capsule and most measurement points, was lower, except for a few areas.