Impact of Forward Head Posture on Postural Stability and Gait Kinematics

Forward head posture (FHP) is a common sagittal-plane postural deviation characterized by anterior translation of the head relative to the trunk. It has become increasingly prevalent among young adults due to prolonged use of computers, smartphones, and other digital devices. FHP has been associated with musculoskeletal dysfunction, altered cervical biomechanics, impaired proprioception, and deficits in postural control.

Recent evidence indicates that altered cervical alignment may influence not only local cervical function but also whole-body balance control and locomotor performance. Changes in head and neck alignment may disrupt vestibular, visual, and somatosensory integration, thereby affecting postural stability and gait efficiency. Although previous studies have independently investigated the effects of FHP on balance or gait, the relationship between postural stability and detailed kinematic gait characteristics in individuals with FHP remains insufficiently understood.

Therefore, this comparative cross-sectional study will investigate the impact of forward head posture on postural stability and kinematic gait characteristics in asymptomatic young adults.

A total of 66 participants of both sexes, aged between 18 and 35 years, will be recruited and assigned into two groups:

Forward Head Posture Group: participants with craniovertebral angle less than 50 degrees.

Control Group: participants with normal cervical posture.

Each participant will attend one laboratory-based assessment session.

Assessment Procedures

• Postural Assessment

Craniovertebral angle will be measured using standardized lateral photography and a smartphone-based digital angle measurement application for group allocation.

• Postural Stability Assessment

Dynamic postural stability will be assessed using the Biodex Balance System. Participants will perform bilateral stance testing at stability level 6 for three trials of 20 seconds each, with 10-second rest intervals. Outcome measures will include:

Overall Stability Index Anterior-Posterior Stability Index Mediolateral Stability Index

• Gait Assessment

Spatiotemporal gait characteristics will be assessed using the Biodex Gait Trainer. Following a familiarization period, participants will walk under two testing conditions:

Self-selected comfortable walking speed Fast walking speed

Outcome measures will include:

Walking velocity Step length Cadence Symmetry indices Temporal gait parameters Primary Objective

To compare postural stability and gait characteristics between young adults with forward head posture and healthy controls.

Secondary Objective

To investigate the relationship between postural stability measures and gait parameters within each group.

Statistical Analysis

Descriptive statistics will be calculated for all variables. Between-group comparisons will be performed using one-way multivariate analysis of variance (MANOVA). Correlation analysis will be performed to examine associations between postural stability and gait parameters. Statistical significance will be set at p < 0.05.

Inclusion criteria

• Cranio-vertebral angle less than 50◦
• Age from 18-35 years old (Young adults)
• BMI from 18.5-24.9
• Participants can walk independently without assistive devices

Exclusion criteria

• Individuals are excluded if they have had:

• Neck trauma, recent fractures, or Surgery or any underlying neurological or systemic conditions affecting the neck
• Pregnancy or Malignancy
• any inability to comprehend or respond to study assessments
• Any known respiratory or cardiovascular conditions that might affect the results of gait analysis
• Vestibular problems, visual problems, and sensory impairment affecting balance
• If they are undergoing current physical therapy or ergonomic intervention for FHP