Effect of improved thoracic kyphosis on forward shoulder posture after mobilization in individuals with thoracic hyperkyphosis.

BACKGROUND: Thoracic hyperkyphosis structurally alters the position of the scapula to cause forward shoulder posture. However, the effect of improved thoracic hyperkyphosis on forward shoulder posture is unclear. The objective of this study was to determine the effect of eight weeks of thoracic mobilization on improving thoracic hyperkyphosis and forward shoulder posture and determine the cutoff change ratio in kyphosis for improving forward shoulder posture using the decision tree method. METHOD: This study included 19 participants with thoracic hyperkyphosis who underwent thoracic mobilization for eight weeks. Forward shoulder posture (acromion-to-the-wall index) and thoracic kyphosis were measured before and after thoracic mobilization. FINDINGS: The intervention significantly improved thoracic kyphosis and forward shoulder posture. The cutoff change ratio in kyphosis for improving forward shoulder posture was >13.79%. In the subgroup analysis of participants with a change ratio of kyphosis >13.79% (seven cases), all patients showed improved forward shoulder posture. In contrast, in the subgroup with a change ratio of kyphosis ≤13.79% (12 cases), eight cases showed improved forward shoulder posture, while four cases showed no improvement. INTERPRETATION: Thoracic mobilization can be recommended in shoulder rehabilitation programs to improve forward shoulder posture to manage and prevent scapular malalignment in individuals with thoracic hyperkyphosis. We suggest that a high probability of improvement in forward shoulder posture can be expected when kyphosis is improved by >13.79%.