Pressure Abrasions – Causes, Symptoms, Treatment

Pressure Abrasions result from prolonged compression of the epidermis. The force required to produce pressure abrasion is, however, minimal. E.g., the use of rough material for hanging produces a ligature mark that is an imprint of the material used.

An abrasion is a partial thickness wound caused by damage to the skin and can be superficial involving only the epidermis to deep, involving the deep dermis. Abrasions usually involve minimal bleeding.^[rx] Mild abrasions, also known as grazes or scrapes, do not scar or bleed because the dermis is left intact, but deep abrasions that disrupt the normal dermal structures may lead to the formation of scar tissue. A more traumatic abrasion that removes all layers of skin is called an avulsion.

Types of Abrasions

Abrasions are classified into three types:

• Linear or scratch abrasions – Linear abrasions are caused by tangential forces resulting in denuding of the epidermis. Linear abrasions are the simplest of injuries and tend to heal by primary intention, without any sequelae. Linear abrasions have significant medicolegal importance, especially when seen over the neck, inner thighs, and genitalia. Linear or semicircular injuries are classically seen as a result of nail scratches, and their presence on the inner aspect of thighs and around female genitalia may indicate resistance in cases of sexual assault. Likewise, nail scratch abrasions on the neck may be suggestive of throttling.
• Grazed or brush abrasions – Grazed abrasions are usually multiple in presentation and result from friction against a broad, rough surface. These are most commonly seen in cases of road traffic accidents as well as in sports falls. Grazed abrasions are caused by the dragging of the body against a rough surface, resulting in the scrapping of the epidermis. The depth of grazed injuries varies depending on the irregularity of the surface, as well as the speed tugging the body. Extensive, grazed abrasions are sometimes referred to as “brush burns.”
• Patterned abrasion – Patterned abrasions are a result of perpendicular force on the epidermis, resulting in an impression of the offending item. Patterned abrasions can be further sub-classified as pressure abrasion and impact abrasion, depending on the duration of contact with the offending object.
  • Pressure abrasions result from prolonged compression of the epidermis. The force required to produce pressure abrasion is, however, minimal. E.g., the use of rough material for hanging produces a ligature mark that is an imprint of the material used.[rx]
  • Impact abrasions result from a swift blow and require considerable force. Patterned abrasions resulting from blows, collisions, and run-over, etc. are examples of impact abrasions.

By degree

• A first-degree abrasion involves only epidermal injury.
• A second-degree abrasion involves the epidermis as well as the dermis and may bleed slightly.
• A third-degree abrasion involves damage to the subcutaneous layer and the skin and is often called an avulsion.

Pathophysiology

Abrasions range from a break in the epithelial lining to damage to the deeper structures, including nerves, blood vessels, muscles, tendons, organs, and even bone.[rx][rx]

Forensic investigations are necessary to determine the extent of the injury and the antemortem or postmortem nature of the wound. The presence of vital reactions, including hemorrhage, cell infiltration, granulation tissue, etc. are indicative of the antemortem quality of an abrasion.[rx]

Diagnosis of Pressure Abrasions

Hostory and Physical exam

Relevant history should be documented, including the time of injury, cause, and mechanism of injury, as well as other relevant details pertaining to the causation as well as management of the injury.

Abrasions are commonly associated with physical trauma; this could result from falls and impact against hard and uneven surfaces, as well as the pressure of impending objects. They are commonly seen along with other forms of blunt force trauma, such as contusions and lacerations.

While the physical examination of abrasions is important for treatment, the medicolegal examination of abrasions is considerably more significant. Abrasions could be present over any part of the body, frequently seen over the exposed parts of the body, especially the head and neck, as well as the extremities. When found over the neck or genitalia, they tend to have a particular significance that could be precarious, if wrongly interpreted.

The physical examination should include the type, size, shape, color, location, size, depth, association with other injuries as well as the presence of extraneous material. The scientific collection and evaluation of these extraneous materials can provide valuable information regarding the scene of a crime, and in linking the suspect to the crime.

The systematic management of the injury for medical and medicolegal purposes will ensure not just treatment of the injury but also help in providing justice to the victim. The medicolegal examination is especially important in injuries over the head and neck and around the genitalia. Injuries around the genitalia could be vital in identifying sexual violence, while minor injuries over the head and neck could be an indication of more serious underlying injuries.

Evaluation

Abrasions are usually simple in nature and frequently small in size. These abrasions usually heal by the first intention and do not leave any scarring. However, the involvement of large surface area can lead to healing by second intentions, resulting in scar formation. This is particularly seen in individuals susceptible to keloid hyperplasia and should be started on steroid therapy to prevent keloid formation.

The medicolegal investigation may require a biopsy of the abrasion for histological examination. The histological examination investigates the stage of wound healing to provide an estimate of time of injury. Wound healing involves a series of coordinated cellular changes that include bleeding and coagulation, inflammatory response, regeneration, and remodeling. The regeneration process further involves migration and proliferation, while remodeling involves extracellular matrix protein and collagen synthesis, as well as the formation of new parenchymal and connective tissue. These processes are four time-dependent phases:

• (i) bleeding and coagulation, begins immediately
• (ii) inflammation, also begins without delay;
• (iii) regeneration, begins in days and lasts for the primary part of the acute healing phase; and
• (iv) remodeling, begins weeks after the injury and can last for longer than a year.[rx][rx][rx]

The information may be further augmented by histochemical analysis of inflammatory cells and cell mediators. This may assist in informing the law enforcement about the time of occurrence of injury. A skin biopsy is relatively painless and can even be performed in the living if required. Histopathology of an injury can provide vital information for the investigation.[rx][rx][rx]

Infection of the injury is another concern and should be managed judiciously. At the same time, the emergence of antibiotic resistance in many organisms should ensure strict follow-up to evaluate compliance and adherence to the full protocol. Injuries should also be swabbed and sent for culture and sensitivity.

Treatment of Pressure Abrasions

Abrasions are usually simple, minor injuries that do not require much medical intervention. A sponsored study showed that wet healing, using polyurethane and hydrocolloid plasters, are found to be more efficient and effective in wound healing.[rx]

First aid for abrasions

An abrasion means that the surface layers of the skin (epidermis) has been broken. Thin-skinned bony areas (like knees, ankles and elbows) are more prone to abrasions than thicker, more padded areas. The scraped skin of abrasion can contain particles of dirt.

First aid treatment includes:

• Clean the wound with a non-fiber shedding material or sterile gauze, and use an antiseptic such as Betadine. If there is embedded dirt, Savlon may be used as it contains an antiseptic and a surfactant to help remove debris. Rinse the wound after five minutes with sterile saline or flowing tap water.
• Don’t scrub at embedded dirt, as this can traumatize the site even more.
• Cover the cleaned wound with an appropriate non-stick sterile dressing.
• Change the dressing according to the manufacturer’s instructions (some may be left in place for several days to a week). If you reapply antiseptic, wash it off after five minutes and then redress the wound.

The abrasion should be cleaned and any debris removed. A topical antibiotic (such as neomycin or bacitracin) should be applied to prevent infection and to keep the wound moist.^[rx] Dressing the wound is beneficial because it helps keep the wound from drying out, providing a moist environment conducive for healing.^[rx] If the abrasion is painful, a topical analgesic (such as lidocaine or benzocaine) can be applied, but for large abrasions. a systemic analgesic may be necessary.^[rx] Avoid exposing abraded skin to the sun as permanent hyperpigmentation can develop.

Due to the loss of the epidermis, the outermost layer of protection of the body, abrasions are particularly susceptible to Clostridium tetani and Staphylococcus aureus, particularly in sports injuries. Tetanus toxoid status should always be checked. Abrasions should be cleansed and dressed, protecting the area from reinjury. Debridement may be required, especially if dirt or other contaminants are found embedded. Prevention of infection is the primary objective of any medical intervention. Antibiotic ointments may be applied; after confirming the allergy history, a dressing may be necessary, depending on the area and depth of the injury. Systemic antibiotics may be indicated and should be judiciously prescribed.

Facial abrasions and considered more serious as these have a higher risk of cicatrization and should be cleaned, debrided, and dressed daily. Dressings may require skin adhesives like the combination of gum mastic, styrax, alcohol, and methyl salicylate or tincture of benzoin.[rx]

Cuts that require medical attention include the following signs:

• They are deep (doctors usually are more concerned with how deep a cut is rather than how long it is, because of the concern that deeper tissues like blood vessels, nerves, or tendons may be damaged)
• They expose any muscle tissue (red) or fat tissue (yellowish)
• They stay open if you let go of the sides of the cut
• They are on a joint or in an area where healing might be difficult (stitching might be needed to keep it closed)
• They remain visibly dirty after being cleaned.
• They continue to bleed longer than 10 minutes.

If no medical attention is needed, treat the cut in the following way:

• Cleanse the cut with tap water. You can also use a mild soap. This process helps remove any debris and bacteria from the cut. Avoid using cotton or wool to clean the cut because fibres may get into the wound and cause infection.
• You can use astringents, alcohol, and antiseptics (e.g., hydrogen peroxide) on the area surrounding the cut, but it is best to avoid using them directly on or in the cut, as they can disrupt the natural healing process.
• Dress the wound with an over-the-counter topical antibiotic to help prevent infection, if necessary.
• Cover the wound with a dressing (cloth bandage) that can help keep the cut moist. If you are not sure what type of dressing to use, ask your pharmacist for a recommendation.

Factors influencing wound repair

Traumatized skin heals at different rates, depending on individual and environmental factors, which include:

• the person’s general state of health
• age – older skin repairs itself at a slower rate than younger skin
• the functioning of the immune system
• dietary factors – skin needs proper nutrition
• external temperature and weather conditions
• stress on the injury site, such as friction
• whether or not the wound becomes infected
• smoking and some drugs (discuss with doctor or chemist)
• pre-existing medical conditions, such as some types of vascular disease.

References