Table 5

Suggested schema for the histological estimation of the time interval from infliction of injury to death in open skin wounds and abrasions

Time intervalHistology
Less than 4 hoursNo distinct signs of inflammation. Histological distinction between antemortem and postmortem skin wounds not possible
4–12 hours4 hours: some polymorph leucocytes perivascularly
8–12 hours: polymorphs, macrophages, and activated fibroblasts form distinct peripheral wound zone
Polymorphs more frequent than macrophages (5:1). Imminent necrosis in central zone
12–48 hours16–24 hours: relative number of macrophages increases, with polymorph to macrophage ratio falling to 0.4:1
After 16 hours older fibrin stains bright red with Martius scarlet blue, whereas before 16 hours “newer” fibrin stains yellow
24 hours: the number of polymorphs and amount of fibrin increase to maximum (remain at this value for 2–3 days)
Cut edge of epidermis shows cytoplasmic processes
24–48 hours: epidermis migrates from the incised edge towards the centre of the wound
At 32 hours and after, necrosis is apparent in the central wound zone
48 hours: macrophages reach maximum concentration in peripheral zone
2–4 days2–4 days: fibroblasts migrate from the nearby connective tissue to the wound periphery
3 days: epithelialisation of small wounds and abrasions complete; thereafter regenerated epidermis becomes highly stratified and thicker than the normal surrounding epidermis
3–4 days: capillary buds appear
4–8 days4 days: first new collagen fibres seen
4–5 days: profuse ingrowth of new capillaries; capillaries continue to proliferate until 8th day
6 days: lymphocytes reach maximum concentration in wound periphery
8–12 daysDecrease in number of inflammatory cells, fibroblasts, and capillaries; increase in the number and size of collagen fibres
>12 days12 days: definite stage of regression of cellular activity in both epidermis and dermis. Vascularity of dermis diminishes. Collagen fibres restored. Epithelium shows stainable basement membrane
At 14 days fibroplasia reaches its peak. Thereafter there is gradual shrinkage and maturation of connective tissue in the wound