In a recent study, Katherine Nash Scafide, PhD, RN, an assistant professor of nursing at Georgetown University School of Nursing & Health Studies, analyzed how different characteristics play a factor in the bruise healing process. Her research is unique in that, up until now, most research into bruise healing has involved small sample sizes. Scafide’s study comprised 103 participants who varied in gender and skin color.
Source: http://online.nursing.georgetown.edu/the-forensic-science-behind-bruise-healing-infographic/
1. Forensic health experts are often asked by the criminal justice system to identify the
age of bruises in victims of violence. Using objective, forensic data to evaluate a victim’s
bruises may help support or disprove an injury’s origin in a civil or criminal proceeding.
To date, however, research in this area has been limited. A recent study led by
Katherine Scafide, PhD, RN, an assistant professor of nursing at Georgetown University
School of Nursing & Health Studies, provides a foundation for understanding how
bruises change color as they age and how they heal differently based on gender, skin
color, and the role of fat below the surface of the skin.
THE
FORENSIC SCIENCE
B E H I N D
BRUISE HEALING
METHOD
RESULTS
CONCLUSION
In this study, a final sample of 103 participants was used. The following are the
assumptions and methods used to gather data.
The sample included English-speaking, healthy adults between the ages
of 18 and 45. An upper age limit of 45 was used so that it wasn’t
necessary to factor in the effects of declining estrogen on inflammation.
18 45
AGES
The sample excluded subjects who had:
Taken medication in the previous two weeks
that could impact coagulation or inflammation
Been diagnosed with a condition impacting
coagulation, inflammation, or estrogen production
An illness with a fever in the previous seven days
Donated blood or a blood product in the
previous 60 days
An injury or intra-muscular injection to the upper
arm in the past 30 days
Used self-tanning spray, cream, or been in a tanning
booth in the two to four weeks prior
Had any observable lesions on the upper arm, including
tattoos and acne
Color was measured objectively using a colorimeter, which converts
reflected light into numerical values.
After a baseline reading of skin color was done, participants were bruised
in the selected, exposed upper arm with a paintball pellet on day one.
The subjects were positioned against a rubber-covered plywood opening
where the arm was struck with a paintball pellet, 17 mm in size, from a
distance of 20 feet.
Thirty minutes after the paintball’s impact, the resulting skin discoloration
was marked and colorimetry measures were taken.
Study participants were observed for four consecutive days.
Physical examinations of the bruises were done, weight was taken, body
mass index (BMI) was calculated, triceps fat was measured, bruise size
was determined, and a colorimeter was used to measure color.
Individual Typology Angle (ITA°) was used to categorize skin color.
Participants were asked not to apply ice, massage the impact site, or
take anti-inflammatory medication.
DAY 1
DAYS 2-5
BASELINE
TRAUMA
30 MINUTES POST TRAUMA
HEALING PROCESS
AVERAGE PARTICIPANT
FINDINGS
Most subjects were
right handed.
There were similar
numbers of men and
women with light, medium,
and dark skin color
No significant difference by
gender was found in skin
color, natural hair color, BMI,
or dominant hand.
*Females had a significantly higher amount of triceps fat.
All subjects developed
a bruise within 30
minutes following the
paintball impact.
Participants with light skin color
were more likely to have
blonde/red or brown hair.
Central clearing was noted in 35.9% of the
bruises. Central clearing is a central pallor or
“donut-effect” that occurs when blood is forced
away from the point of impact. Medium skin
color subjects had central clearing more often
than light skin color subjects.
Participants with central clearing were more
likely to have larger bruises.
The size of bruises
varied but typically
decreased over time.
Bruises were generally
darker than skin color.
Bruises with central clearing
were typically lighter.
Larger bruises were typically darker.
Individuals with darker skin and
darker hair had darker bruises.
The darkness of a bruise
doesn’t significantly change
in the first four days.
Bruises have significantly more
red than skin color.
Larger bruises lose their
concentration of red faster than
smaller bruises.
Bruises were at their most
blue approximately 24 hours
after the initial trauma.
Between two and three days, the
bruises had a greater concentration
of yellow than skin color.
Larger bruises and those with
central clearing became more
yellow faster.
Medium skin color subjects
had, on average, significantly
redder bruises than subjects
with light or dark skin.
Subjects with medium skin tone had
significantly more yellow in their
bruises than those with dark skin.
AGE
27
TRICEP FAT*
13mm
BMI
25.4
kg/m2
Skin
Tone
Bruise
Coloration
35.9%
1 2 3 40
This study supports the findings of Hughes and Langlois, which found that many
factors contribute to the color of bruises, and these factors must be considered
or controlled when examining the change in bruise color over time.
Skin color is a significant variable when evaluating bruise color.
Bruises on subjects with medium skin color had greater concentrations of red
and yellow than those with light or dark skin color.
The amount of local subcutaneous fat did not significantly explain bruise color
or how it changes.
BMI was not a significant predictor of the change in bruise color.
Gender did not play a significant role in predicting bruise color or how it
changes over time. This contradicts the findings of Hughes and Langlois.
The study provided a detailed analysis of the change in bruise colorimetry
during the first four days of bruise development.
Further research on the aging of bruises is needed.
This study was conducted with the approval of the Johns Hopkins
Medicine Institutional Review Board. The protocol was developed and
reviewed in accordance with the ethical principles outlined in the Belmont
Report and the United States Department of Health and Human Services
Federal Policy for the Protection of Human Subjects. Written informed
consent was obtained from each subject prior to participation.
ETHICS REVIEW
COLORATION
HEALING PROCESS
SOURCE:
http://link.springer.com/article/10.1007%2Fs12024-013-9452-4# created by: