Pressure necrosis is the primary cause of wound dehiscence.

Wound dehiscence occurs because the distracting forces in a wound exceed the holding forces. Critical analysis of these forces indicates that pressure necrosis from sutures is the primary factor in wound dehiscence. Other factors play a secondary role, either in delaying the healing of a wound or in increasing the stress on it. To prevent pressure necrosis, a mechanically sound method of cradling the entire wound in a series of wide-biting encircling retention sutures, 2.5 cm apart, is described. Each retention suture is tied loosely with a measured tension sufficient to hold the wound together while avoiding pressure necrosis. In this prospective study the tension used is equal to 300 g, far less than surgeons usually use. There were no wound dehiscences in 787 consecutive abdominal incisions repaired by this method.