下列哪項因素對壓瘡（壓力性損傷）的發生貢獻最大？
Which factor most contributes to the development of pressure injuries?
- AFrequent repositioning頻繁重新定位
- BMaintaining skin moisture保持皮膚濕潤
- CHigh protein intake高蛋白攝取
- DProlonged immobility✓ 正解長期活動受限
壓力性損傷（Pressure Injury）的形成機制主要是由於軟組織在骨凸處受到持續性的壓力，導致微循環受阻、組織缺血缺氧。長期不動（Prolonged immobility）是導致此過程的最直接因素，因為病人無法藉由改變姿勢來緩解局部壓力。除了不動之外，剪力、摩擦力與潮濕也是重要輔助因子，但長期不動是臨床上最需透過翻身計畫來介入的核心問題。
Pressure injuries develop primarily when soft tissue over bony prominences is exposed to sustained pressure, impairing microcirculation and producing tissue ischemia and hypoxia. Prolonged immobility is the most direct contributor to this process, because clients cannot relieve local pressure by repositioning themselves. In addition to immobility, shear, friction, and moisture also play important contributory roles, but prolonged immobility is the core clinical problem that is most effectively addressed through repositioning programs.