Journal of Medicine and Health Research

Background: Forward head posture (FHP) is increasingly prevalent among young adults due to prolonged exposure to smartphones and computer-based tasks. While external postural parameters such as the cranio‑vertebral angle (CVA) are commonly used for screening, their relationship with sub‑occipital and upper cervical radiographic alignment remains inadequately defined.

Objective: The present study evaluates the association between long-term forward head posture and sub-occipital vertebral alignment using radiographic and postural measures.

Methods: A retrospective observational analytical study was conducted on 30 young adults (20–28 years) with prolonged device use. External posture was assessed using the cranio-vertebral angle (CVA). Upper cervical alignment was evaluated on open-mouth odontoid radiographs by measuring the atlanto-occipital joint axis angle (AOJAA), coronal atlanto-axial joint inclination angle (CAAJI), and odontoid lateral                  mass interval (OLMI). Group comparisons were performed using independent t-tests, and associations between CVA, radiographic parameters, and neck pain intensity were analyzed using Pearson correlation coefficients.

Results: Participants with forward head posture demonstrated significantly higher CAAJI and OLMI values compared with controls (p = 0.020 and p < 0.001, respectively), while AOJAA showed no significant between-group difference (p = 0.081). CVA demonstrated a moderate negative correlation with CAAJI (r = −0.430, p = 0.018), whereas correlations with AOJAA and OLMI were weak and non-significant. Mean neck pain intensity was mild to moderate.

Conclusions: Forward head posture in young adults is associated with measurable coronal-plane adaptations at the atlanto-axial joint. CAAJI appears to be a sensitive radiographic indicator of early upper cervical biomechanical alteration, even when external postural deviation and pain severity are moderate.