[Impasses of cutaneous cicatrization]. 
The neurovascular aspects of healing failure have a common pathogenetic factor, the diminished delivery of oxygen to peripheral tissues.  Recent hypotheses on the pathogenesis of ulcers via venous insufficiency underline the presence of pericapillary fibrinous sleeves which justify the use of prolonged venous compression.  Encouraging preliminary results have been reported concerning the use of topic vasodilators (prostaglandin E2, ketanserin) in the treatment of leg ulcers.  Diabetic neurotrophic ulcers are of multifactorial origin, with disorders of the sympathetic nervous system having a determinant role.  Whatever the cause of healing failure, diagnosis and treatment should also take into account general factors, whether extrinsic, or intrinsic.