Postural balance is an essential capacity for functional autonomy and the performance of activities of daily living, relying on the continuous integration of visual, vestibular, and somatosensory information. Within this system, the upper cervical region plays a particularly important role, as it contributes to the orientation of the head in space and to the coordination between the head, eyes, and trunk. Due to their deep location between the occiput, atlas, and axis, the suboccipital muscles have a high proprioceptive significance and are frequently associated with cervical position control and sensorimotor regulation.

Changes in muscle tension, stiffness, or dysfunction in this region may alter the quality of afferent information transmitted to the central nervous system, potentially interfering with postural stability, head position awareness, body sway, and center of pressure control. In this context, the suboccipital inhibition technique is used in osteopathic practice as a manual intervention aimed at reducing myofascial tension, promoting relaxation of the upper cervical musculature, and potentially normalizing proprioceptive input.

Postural balance is a fundamental component of human motor function and is essential for maintaining functional autonomy and performing activities of daily living. It relies on the continuous and dynamic integration of sensory inputs from the visual, vestibular, and somatosensory systems, which are processed by the central nervous system to generate appropriate motor responses. These responses allow the body to maintain the center of mass within the base of support through constant postural adjustments.

Within this complex sensorimotor system, the upper cervical region plays a critical role in postural control. This region is responsible for the precise orientation of the head in space and contributes significantly to the coordination between the head, eyes, and trunk. The suboccipital muscles-namely the rectus capitis posterior major and minor, and the obliquus capitis superior and inferior-are deeply located between the occiput, atlas, and axis, and are characterized by a high density of muscle spindles. This anatomical feature suggests a strong proprioceptive function, making these muscles key contributors to cervical position sense and sensorimotor regulation.

In addition to their proprioceptive role, the suboccipital muscles are anatomically and functionally connected to the dura mater through the myodural bridge. This structure is thought to play a role in both mechanical and sensory integration, linking muscular activity with the central nervous system. Furthermore, the upper cervical region contains joint mechanoreceptors that provide additional afferent input, contributing to reflex mechanisms such as the cervico-ocular, cervico-collic, and tonic neck reflexes, which are essential for maintaining postural stability and gaze control.

Alterations in muscle tone, increased stiffness, or dysfunction in the suboccipital region may disrupt the quality of afferent information transmitted to the central nervous system. Such disturbances can impair proprioceptive accuracy and interfere with postural control mechanisms, potentially leading to increased body sway, altered head positioning, and changes in center of pressure (CoP) behavior. Since CoP displacement reflects the neuromuscular strategies used to maintain balance, it serves as an objective measure for assessing postural stability.

The suboccipital inhibition technique is commonly used in osteopathic practice as a manual intervention aimed at reducing myofascial tension in the upper cervical region. By promoting muscle relaxation and potentially restoring normal proprioceptive input, this technique may contribute to the optimization of postural control mechanisms. Previous studies have demonstrated its effects on cervical mobility, pain reduction, and flexibility; however, evidence regarding its immediate impact on postural balance remains limited and inconclusive.

Given the theoretical and neurophysiological rationale supporting the role of the suboccipital region in postural regulation, further investigation is warranted. The present study aims to evaluate the immediate effects of the suboccipital inhibition technique on postural balance in healthy young adults, using objective measures derived from center of pressure analysis, specifically Mean CoP and Mean Velocity.

Inclusion Criteria:

• Healthy individuals (defined by the absence of the exclusion criteria listed below)
• Aged between 18 and 35 years
• Signed informed consent form

Exclusion Criteria:

• Recent history of falls
• History of spinal or foot surgery
• Cervical fractures
• Known postural instability
• Suspected neurovascular compromise
• Neurological deficits
• Neurological or vestibular disorders
• Use of medication or substances that may affect the nervous system
• Osteopathy students from the 2nd, 3rd, and 4th academic years