[libribook.com] Traumatic Scar Tissue Management 1st Edition

Prolonged Inflammation
Inflammation will persist as long as debris is present at the wound site.
Ineffective ‘clean-up’ during the inflammatory stage may prolong healing. Both
bacteria and endotoxins can lead to the prolonged elevation of pro-inflammatory
cytokines (e.g. interleukin-1 (IL-1)) extending this stage beyond its normal
length of time. Consequently this can result in the wound transitioning into
chronic state with failure to heal. In vitro evidence suggests that the presence of
macrophages delays wound contraction, therefore the withdrawal of
macrophages from the wound site may be essential for subsequent stages to
occur in normal sequence and timing. Prolonged inflammation can lead to an
increased level of matrix proteases (e.g. collagenase) that are known to degrade
the ECM or conversely the excessive/prolonged presence of cytokines that
stimulate excessive collagen production – resulting in pathophysiological scars
(Edwards & Harding 2004, Menke et al. 2007).