Abstract
Background/Objectives: The present study aimed to investigate the relationship between forward head posture (FHP) and the mechanical properties of muscles as well as the influence of FHP on them. Methods: To define participants with FHP, craniovertebral angle (CVA) was measured. All participants were divided into two groups in accordance with their CVA: the experimental group (FHP) consisting of participants with a CVA below 50°, and the control group (CON) consisting of participants with a CVA above 50°. The tone, stiffness, and elasticity of the upper trapezius muscle (UT), the middle trapezius muscle (MT), the lower trapezius muscle (LT), the sternocleidomastoid muscle (SCM), the splenius capitis muscle (SC), the pectoralis major muscle (PM), and the serratus anterior muscle (SA) were measured using MyotonPro (Myoton AS, Tallinn, Estonia). Results: Both tone and stiffness in the UT were statistically significant (p < 0.05). In addition, stiffness in the LT was statistically significant (p < 0.05). No significant differences were found in tone, stiffness, and elasticity of the MT, SCM, SC, PM, and SA muscles (p > 0.05). A significant correlation was found between FHP and both tone and stiffness in the UT (r = −0.731, p = 0.000; r = −0.749, p = 0.000, respectively). No significant correlation was found between FHP and tone, stiffness, and elasticity of the MT, LT, SCM, SC, PM, and SA muscles. Conclusions: Since the UT was the muscle in which changes in mechanical properties were first induced by FHP, an approach targeting UT is necessary as a priority when treating patients with FHP.