Bruising in Children

Introduction

Bruises in children are commonplace. You’re likely to find one accompanying a fall, next to a scratch or a scrape in a variety of situations. Medically speaking, a bruise forms when blood escapes into the skin or subcutaneous tissue (or both), when a nearby blood vessel (usually smaller capillaries) bursts as a result of blunt force. Accidental bruises in children occur often in the course of routine play. However, bruises can also indicate child abuse if they are observed in specific patterns over time.

As we go over bruising in children here, we’ll be borrowing from: T. Stephenson. Bruising in children. Current Pediatrics (1995) 5, 225-229.

Those in the medical and child abuse prevention prevents are taught any “non-accidental” bruise represents a case of child abuse. They are wrong about that. However, for purposes of this article, we’ll set that aside and simply use the language as presented in the paper referenced above.

What Affects the Appearance of a Bruise?

A number of factors can contribute to the appearance of a bruise, including:

The impact of the blunt force that causes the bruise.
The vascularity of veins and blood vessels beneath the skin.
Diseases that impact clotting abilities or connective tissues.
Taut or loose skin. Loose skin tends to bruise more easily.
Muscle tone or fatty tissue underneath the bruise. Bruises in areas well supported by muscle will be minimal compared to bruises that occur where there is excess subcutaneous fat.
Age. Babies and the elderly usually bruise more easily.
Sex. Women may bruise more easily than men.
Skin color. Bruises are more obvious on paler skin.

What does an accidental bruise look like?

Children frequently present with bruises from falling off of a bike, or tripping over a shoelace, so occasional bruising as the average child engages in everyday activity is to be expected.

In a 1982 study, researchers observed a few key patterns in the way that 400 children from 2 weeks to 11 years old bruised over a 10-month period. They found the following trends in accidental bruising:

By the end of year 3, almost 60% of the children had some type of visible wound—and bruises were the most common. Many of these bruises were associated with nearby cuts or scrapes.
More than 20% of the bruises found were on the lower legs, followed by 9.25% on the thighs and buttocks and 8.5% on the arms. Infants and toddlers were the exception though, since injuries to the lower legs were uncommon in children younger than 18 months (presumably because they aren’t running around on their own outside).
Bruises to the head and face were rare (only in 6.5% of their cases, and most of these were toddlers), and bruises to the back were even less common (mostly in children older than 6 years). Just 1.5% of children had bruising on the chest.
Accidental bruising in children 2 weeks-2 months old was practically non-existent (only 2 instances reported). Injuries to the genitalia were also extremely rare.

See Roberton, D M et al. “Unusual injury? Recent injury in normal children and children with suspected non-accidental injury.” British medical journal (Clinical research ed.) vol. 285,6352 (1982): 1399-401.

Bruising as a Result of Disease

There are a few conditions that can predispose some children to unexplained bruising. These conditions are marked by the absence of blood clotting ability or weak connective tissue.

Henoch-Schönlein Purpura, for example, can present with unexplained bruising in children due to a lack of clotting factors. This is often diagnosed after examining family and medical history.

In other cases, like with Ehlers-Danlos or Marfan’s syndrome, individuals are prone to bruising due to abnormal elastic tissue. If severe and unexplained bruises appear on a child (particularly if they may lead to legal action), undertaking a clotting screen to identify these disorders is recommended.

Non-Accidental Bruises

Bruises are found on the majority of children suffering from physical abuse. Non-accidental bruises often display different characteristics from accidental, self-inflicted bruises typically found in children.

Most bruises that are the result of physical abuse are multiple. The exception is when there is a one-time injury, such as a slap mark on the face.
Though there is some debate on the accuracy of determining the age of a bruise, there are often several bruises in different states of healing that indicate repeated trauma to the child’s body.
Bruises found on the head and face are often non-accidental. These may be from slaps to the face, blows to the head, or fingermarks from force-feeding the child.
Bruising on all parts of the body except the lower legs is more common in non-accidental bruising.
Bruises to the outside of the ear and the side of the lower jaw are normally associated with non-accidental injuries.
Black eyes can occur in all children, but two black eyes on the same child are uncommon. Apart from the case where the forehead hits a hard surface and blood flows into the area around the eye sockets, two black eyes is generally cause for concern.

Specific Patterns of Non-Accidental Bruises

Multiple bruises about 1 cm in diameter may be fingertip bruises caused by poking or tightly gripping the child.
Suction bruising (“love bites”) with petechial hemorrhaging.
Five closely grouped linear marks, often accompanied by petechial hemorrhaging, on the checks or buttocks, can signify a hand slap. Ring marks, including scratches on the body, are also frequently observed.
A single linear bruise may be caused by a belt or a cane.
Bruises consistent with the weave of the clothing worn when injured.

Conclusion

Bruising is very common in young children, but it occurs in a relatively predicable display of normal injuries sustained through play. Outside of a small number of diseases that are associated with unexplained bruising, there are a few specific patterns that emerge in cases of alleged abuse.