A 40-year-old patient with a chronic diabetic foot ulcer (5 cm, Wagner Grade 2) undergoes negative pressure wound therapy (NPWT). Which cellular and molecular mechanism best explains the therapeutic effect of NPWT on wound healing?
- A Occlusion of wound surface reducing bacterial colony counts by >99%
- B High oxygen tension in the wound microenvironment accelerating collagen synthesis
- C Osmotic draw of exudate reducing wound biofilm
- D Mechanical deformation of cells stimulating cytoskeletal stretch and promoting fibroblast proliferation, angiogenesis, and granulation tissue formation ✓
Explanation
NPWT (vacuum-assisted closure, VAC therapy) applies sub-atmospheric pressure (typically -125 mmHg), causing mechanical deformation of wound tissue. This mechanotransduction effect stimulates cell proliferation through integrin-mediated signaling and cytoskeletal stretch, promotes angiogenesis via VEGF upregulation, accelerates granulation tissue formation, reduces wound edema (by removing excess exudate), and draws wound edges together. It does not achieve 99% bacterial reduction by itself; infection control still requires debridement and antibiotics. It is indicated for chronic wounds, open abdominal wounds, and split-thickness skin graft fixation.
Reference: Bailey & Love's Short Practice of Surgery, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.