Effectiveness of lower cervical self-sustained natural apophyseal glide (SNAG) in improving regional function among individuals with cervical extension dysfunction

Background. Cervical extension dysfunction is a common movement impairment of the cervical region. The Mulligan sustained natural apophyseal glide (SNAG) is frequently used in clinical practice to enhance movement, but there is limited evidence regarding its effect on improving regional function. This study aims to determine the effect of lower cervical SNAG on extension movement gain. Materials and methods. This quasi-experimental study enrolled 60 subjects with their consent. They were conveniently allocated into three groups. Self-SNAG, with or without specific exercises targeting neck and scapular muscles, and standard exercises were administered over 7 sessions spread across two weeks. Pain severity, cervical extension range, deep neck flexor strength, regional disability, and segmental facet position using roentgenogram were measured pre- and post-intervention. Results. Significant improvements were observed in cervical extension range, deep flexor strength, and neck disability across all groups (p < 0.001). The group receiving SNAG and specific exercises demonstrated significantly better improvement (p < 0.005) in all outcomes compared to the other groups. The cervical segmental facet position also changed significantly following SNAG application (p < 0.001). Conclusions. The study findings suggest that self-administered SNAG targeting the lower cervical segment, when combined with specific exercises, changes cervical segmental facet position, improves muscle performance, enhances regional function, and reduces pain among individuals with cervical extension dysfunction.