Tissue Laxity
Definition
The looseness of subcutaneous tissue. High laxity (eyelids, scrotum, elderly skin) allows blood to spread widely from a relatively small vessel injury, producing a bruise that looks larger and older than the injury mechanism would suggest.
- Definition
- Looseness of subcutaneous tissue at a body site
- High-laxity sites
- Eyelids, scrotum, elderly skin
- Effect
- Blood spreads widely from a small vessel injury
- Consequence
- Bruise appears larger or older than the mechanism suggests
Common questions
Why is tissue laxity important when estimating bruise age?+
A widely spread bruise from a high-laxity site can look like an older, more evolved injury simply because of how the blood tracked through loose tissue, so an examiner unaware of the site's laxity could misjudge the bruise's age or the force involved.
Does high tissue laxity mean a smaller impact caused the visible bruise?+
The visible spread can be larger than the impact area, but that does not by itself indicate a smaller force. It means the size and shape of a bruise at a lax site are poor indicators of the impacting object's size or the force applied.
Related terms
- Bilirubin
- A yellow-orange breakdown product of biliverdin, seen as the yellow-brown phase of a resolving bruise. Its appearance indicates advancing haemoglobin degradation.
- Biliverdin
- A green breakdown product of haemoglobin, appearing as the blue-green phase of bruise colour change. Biliverdin is then converted to bilirubin.
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- Oxyhaemoglobin
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