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Types of wounds are usually described by how the injury happened (cut, scrape, bruise, burn, pressure) and by a few classification axes: open or closed, acute or chronic, intentional or unintentional. This guide sets out the nine common wound types with the definitions used in a nursing textbook, then the classification axes and the wound features that the CDC links to higher tetanus risk.
General information only, not medical advice. It does not diagnose or direct treatment of any individual wound; a clinician decides care.
Overview: what counts as a wound
MedlinePlus describes wounds as injuries that break the skin or other body tissues, including cuts, scrapes, punctured skin and wounds from surgery. The OpenStax Fundamentals of Nursing chapter on wound classification (CC BY 4.0, checked 2026-10-30) groups wounds in several overlapping ways, so one wound can carry several labels at once, for example “open, acute, unintentional laceration”.
Types of wounds table
Definitions below follow the OpenStax table “Types of Wounds”. The open or closed column is explained under the table.
| Type | Definition (OpenStax) | Open or closed |
|---|---|---|
| Incision | A surgical cut made in skin or flesh | Open |
| Contusion | A region of injured tissue or skin in which blood capillaries have been ruptured (bruise) | Closed |
| Abrasion | An area of skin or tissue damaged by scraping | Open |
| Laceration | A deep cut or tear in the skin or flesh or underlying tissue | Open |
| Puncture | A wound made by a pointed object | Open |
| Penetration | A wound caused by an object that pierces the skin and lacerates or damages adjacent tissue | Open |
| Avulsion | A forcible tearing off of skin or another part of the body | Open |
| Burn | An injury to the skin caused by thermal, electrical, chemical, or electromagnetic energy | Open (skin injury) |
| Ulcer | An open sore caused by poor blood flow | Open |
The open/closed column applies the OpenStax rule: an open wound is a break in the skin or mucous membranes, while a closed wound has no break in the skin and occurs under the surface. The contusion is the textbook’s closed example; the burn and ulcer rows are editorial readings of the same rule.
What are the 4 main types of open wounds?
Abrasion, laceration, puncture and avulsion are four of the nine entries in the table above, all open; the textbook also lists incision, penetration, burn and ulcer as separate types.
What is a closed wound?
A closed wound does not break the skin and occurs under the skin’s surface. A bruise (contusion), where capillaries have ruptured, is the example OpenStax gives.
How wounds are classified
Acute and chronic
An acute wound occurs suddenly and progresses through the expected stages of healing. OpenStax describes a chronic wound as one where little to no healing occurs for at least three months.
Intentional and unintentional
An intentional wound is planned, made for a treatment purpose under sterile conditions (a surgical incision). An unintentional wound results from unexpected trauma.
Pressure injuries
OpenStax defines a pressure injury as a localized ischemic lesion of the skin and underlying tissue, and lists these stages:
- Stage I: localized nonblanchable erythema of intact skin
- Stage II: partial-thickness skin loss involving the epidermis or dermis
- Stage III: full-thickness skin loss where the adipose, granulation and deeper tissues are visible
- Stage IV: full-thickness skin loss with extensive destruction and necrosis
- Deep tissue injury, and unstageable injuries where slough or eschar obscures the extent
The same chapter distinguishes friction (two surfaces rub together and can remove the top layer of skin) from shear (one tissue layer slides over another).
Wound features linked to higher tetanus risk
The CDC (tetanus page, last reviewed 8 September 2026, checked 2026-10-30) says tetanus risk is higher if a wound is deep or contaminated with dirt. It lists puncture or deep wounds such as stepping on a nail, wounds containing dirt, soil, feces or saliva (an animal bite for example), and wounds with dead tissue such as burns, fractures, crush injuries or frostbite.
Supplies for wound care
Which dressing or bandage suits a wound is a clinical decision. For general descriptions of the product categories, see what a wound dressing is, what a bandage is, non-adherent dressings, hydrocolloid wound care and the wound care supply selection guide. Catalogue listings are at wound dressings.
FAQ
What counts as a chronic wound?
One in which little to no healing occurs for at least three months (OpenStax Fundamentals of Nursing, checked 2026-10-30).
Which wound features does the CDC link to higher tetanus risk?
Per the CDC, puncture or deep wounds, wounds containing dirt, soil, feces or saliva, and wounds with dead tissue (burns, fractures, crush injuries, frostbite).
Is a bruise a wound?
OpenStax lists contusion (bruise) as a wound type; it is a closed wound because the skin is not broken.
Sources
- OpenStax, Fundamentals of Nursing, 24.3 Wound Classification, CC BY 4.0, via LibreTexts (https://med.libretexts.org/bookshelves/nursing/fundamentals_of_nursing_%28openstax%29/24%253a_skin_integrity/24.03%253a_wound_classification); last modified 24 December 2024; checked 2026-10-30.
- MedlinePlus (NLM), Wounds and Injuries (https://medlineplus.gov/woundsandinjuries.html); last updated 10 March 2023; checked 2026-10-30.
- CDC, About Tetanus (https://www.cdc.gov/tetanus/about/index.html); last reviewed 8 September 2026; checked 2026-10-30.
