Background <p>Postural kyphosis is considered a common spinal alignment disorder characterized by an increased thoracic curvature without structural vertebral abnormalities. Changes in sagittal alignment may affect load distribution throughout the body and alter sensorimotor integration, thereby influencing somatosensory inputs and body perception. However, to our knowledge, no previous study has simultaneously evaluated trunk and plantar tactile sensitivity, proprioception, and body image perception in young adults with postural kyphosis. Understanding these multidimensional alterations is clinically important, as they may contribute to impaired postural control and inform rehabilitation strategies. Therefore, this study aims to compare trunk and plantar tactile sensitivity, trunk and ankle joint position sense, and body image perception between young adults with postural kyphosis and healthy individuals of similar age.</p> Methods <p>This analytical cross-sectional study included 62 individuals aged 18–25 years, comprising 31 individuals with postural kyphosis and 31 healthy controls. Thoracic kyphosis angle was measured using the flexicurve method. Tactile sensation in the trunk and foot regions was assessed using the Semmes-Weinstein monofilament test, while proprioception was evaluated using a digital goniometer to assess joint position sense. Body image sensation was assessed using the Kyphosis-Specific Spine Appearance Questionnaire (KSAQ).</p> Results <p>Individuals with postural kyphosis demonstrated significantly reduced tactile sensation at the T4, T5, and T6 vertebral levels (<i>p</i> &lt; 0.001) and at the first metatarsal region of both feet (<i>p</i> &lt; 0.05) compared with healthy controls. Proprioceptive sensitivity was significantly lower in the postural kyphosis group during trunk flexion, extension, and right and left lateral flexion, as well as during ankle dorsiflexion and plantar flexion (all <i>p</i> &lt; 0.001). In addition, KSAQ scores were significantly higher in individuals with postural kyphosis than in healthy controls (<i>p</i> &lt; 0.001).</p> Conclusion <p>The findings of this study suggest that postural kyphosis is associated not only with altered spinal alignment but also with changes in tactile sensation, proprioception, and body image in young individuals. These results highlight the importance of considering sensory–motor integration and psychosocial aspects when planning rehabilitation strategies for individuals with postural kyphosis.</p> Trial registration <p>ClinicalTrials.gov, registered on 15 May 2024 (Identifier: NCT06420869). Retrospectively registered.</p>