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<div><p>Objective</p><p>This study aimed to assess the impact of Mulligan Reverse Natural Apophyseal Glides (RNAGS) applied to the upper thoracic region on pain, movement limitation, and function in individuals with mechanical neck pain.</p><p>Methods</p><p>Conducted between January 2021 and May 2021, the study involved 69 participants randomly assigned to a sham group, physiotherapy group, and Mulligan group. A two-week, 11-session treatment program was administered with shared physiotherapy interventions and stretching exercises to all groups. The Mulligan group received additional mobilization with the Mulligan RNAGS technique. The sham group received sub-standard Mulligan mobilization. Outcome measures included Range of Motion (ROM), Visual Analogue Scale (VAS), and Neck Disability Index (NDI).</p><p>Results</p><p>No baseline differences were found in measurements among the groups. After the intervention, all groups showed increased ROM and decreased VAS and NDI scores (p<0.001). The Mulligan group exhibited significantly greater improvement in VAS, ROM, and NDI compared to other groups (p<0.001). The sham group demonstrated greater improvement in NDI and extension ROM compared to the physiotherapy group (p<0.001).</p><p>Conclusion</p><p>Mulligan RNAGS technique in the upper thoracic region proved beneficial for pain relief, range of motion, and functionality in mechanical neck pain. Long-term effects warrant further exploration through population-based studies.</p></div>