Contusion/Bruise-Factors and Color changes
- The laxity of tissues –
- Lax scrotal tissues allow more extravasation of blood
- Restrictive fascial planes prevent the accumulation of extravasated blood.
- The Turkish torture method ‘falaka’ relies on this principle – the soles of the feet are targets of a beating with sticks, causing severe pain but little outward sign of any injury
- The location of the bruise
- Highly vascular areas will be more heavily bruised, and tissues overlying bony support will bruise more readily than the unsupported and resilient tissues of the abdomen
- Age –
- Take longer to resolve in the elderly who tend to have more fragile vessels
- Children have a comparatively smaller volume of ‘supporting tissue’;
- The person’s skin pigmentation –
- Easily recognised in those with pigmented skin.
- The force of impact –
- The amount of force used may determine the extent of bruising, as well as the characteristics
- The extent of bruising is also inversely proportional to the sharpness of the object causing it – bruises represent blunt force trauma;
- The existence of co-morbidities –
- Some people have the tendency to bruise more easily than others, particularly those with bleeding diatheses, chronic alcoholism and liver failure, scurvy and hypertension. I
- The use of drugs –
- particularly anticoagulants such as warfarin and steroids;
- Any delay in presentation –
- bruises ‘migrate’ along anatomical fascial planes, and may appear some time after the injurious assault; and
- The effects of treatment –
- for example the timely application of ice-packs etc
Colour changes in the contusion
- Colour changes in the contusion is due to disintegration and haemolysis of red blood cells.
- At first : Red (oxyhemoglobin)
- Few hours to 3 days : blue (reduced hemoglobin)
- 4th day : Bluish-black to brown (haemosiderin)
- 5-6 days : Greenish (haematodin)
- 7-12 days : Yellow (Bilirubin)
- 2 weeks : Normal (absorption of pigment)
- Pigments are removed by phagocytes.
Healing process depends on:
- Size and situation of contusion.
- Age and physique of the person
- Presence and absence of disease.
- Sharp,well defined margins.
- Swelling of the tissues.
- Discoloration of the skin.
- Extravasation of blood into the true skin and subcutaneous tissue.
- Doubtful cases-Microscopic examination.
- Can be produced with in 1-2 hrs after death.
- If body is decomposed it is difficult to differentiate between antemortem and postmortem contusions.
Self inflicted contusion
- Rare-can be inflicted by irritant substances like Marking nut(Latin name: Semecarpus anacardium),root of plumbago zeyloxica or rosea.
- Can be differentiated by chemical analysis.
|Artificial bruise||True bruise|
|Caused by Juice of marking nut, calotropis,Plumbago rosea||Trauma|
|Dark brown color||Color changes|
|Well defined margins||Merge with surrounding areas|
|Redness seen in the surrounding skin||Redness in the site of injury|
- Shape and size of contusion,indicates the weapon used.
- Their position,arrangement,circumstances and surroundings.
Colour Changes of Bruise:
|Few hrs to 3 days||Blue||Reduced Hb|
|4th day||Bluish black to brown,||Hemosiderin|
- A contusion can be differentiated from postmortem staining by doing Incision test.
- Postmortem staining is easliy washable.
- Seen on exposed easily accessible parts
- Dark brown in colour
- Well defined wound covered with vesicles
- Inflammation around the surrounding site
- Vesicles on the fingertip and other parts of the body due to scratching