Cyber Week Sale - 15% Off*, Code: HPCW23

Online since 2002 |   866-316-0162

Articles and News

Phases of Wound Healing

Phases of Wound Healing
Christine Kijek, RN, BSN, WON

The body uses a systematic approach for healing a break in the skin, the largest organ of the body. It is the first line of defense against environmental organisms. Once broken, our bodies are at risk for fluid loss and invasion of opportunistic invaders.

4 Phases of Wound Healing

There are four phases to wound healing:

Phase 1- Hemostasis

This phase starts as soon as the wound occurs. Blood vessels constrict and platelets (clotting factor in the blood) are activated and sent to the injury site to stop blood loss. Once platelets are activated, they release growth factors and cytokines (control wound healing). A fibrin structure is created by the platelets which help cells migrate during this phase. This phase lasts from 1-2 days.

Phase 2- Inflammation

The cytokines and growth factors released in phase 1 start the inflammatory phase. The fibrin matrix has been created and the bleeding has stopped.

The goal of this phase is to clean any foreign material and dead tissue from the wound and control bacteria that may have entered the wound. White blood cells (WBC) - specifically, neutrophils and monocytes - are sent to the wound. The neutrophils destroy bacteria. Once destroyed, macrophages - another component of the WBC - are created by the monocytes. These macrophages eliminate dead bacteria and cellular debris. Macrophages release additional cytokines that help transition into the third phase of wound healing, proliferation.

The inflammatory phase overlaps with the next, proliferation phase. Macrophages play a key role in the early phases of repair. Impaired macrophage activity will delay wound healing, often keeping the wound in the inflammatory state.

In normal wound healing, the inflammatory phase typically lasts from day 1 to day 10.


Phase 3 – Proliferation

This phase is also known as the regeneration phase. The cytokines in the inflammatory phase along with growth factors signal fibroblasts to enter the area of injury and generate connective tissue proteins for building granulation tissue. Granulation tissue is also known as the extracellular matrix (ECM).

Fibroblast can normally be found in the undamaged dermal layer of the skin. The largest amount of connective tissue protein in the body is collagen. This builds the scaffolding for new blood vessels and types III collagen. Endothelial progenitor cells in the bone marrow are called to the site to help with blood vessel formation. This is called angiogenesis. The angiogenesis is quite active during this phase and the thickness of the blood vessels is greater than in normal tissue.

Type III collagen is not strong and will convert to collagen type I once the scarring is complete. This will increase the tensile strength of the scar. Full-thickness wounds that heal by secondary intention (from the bottom up) will contract. Special fibroblast cells called myofibroblasts have components of smooth muscle. These cells create a stronger pull, contracting the edges of the wound together, closing the defect in the skin. The color of the scar formation is red.

This phase lasts between 8 and 30 days of the wound.

Phase 4 – Maturation/Remodeling

As the collagen is replaced from type III to type I, the tensile strength of the tissue at 21 days is low. It will increase to 60% about 2-3 months after wound closure. The maximum strength that can be achieved by the end of 1 year is 80%. The thick blood vessels decrease, and most will disappear. The red scar will eventually become pale pink in color as the blood vessels diminish. Contraction of the wound continues to decrease the size of the defect.

Sometimes the body continues to produce new collagen and fails to break down type III collagen, causing a hypertrophic or keloid scar. This is a scar that is raised and overgrown and is reddish to deep pink in color.

Remodeling begins about day 17 and can last up to 2 years.

The time frame for each phase of healing is dependent on normal progression without complication. Wound healing can be delayed based on the body’s failure to manage each phase. Factors that delay wound healing include:

If these factors delay healing, the underlying condition must be resolved for the wound to progress.

The body uses three mechanisms for healing. Granulation tissue formation is when the connective tissue is deposited into the wound bed to fill the defect. Contraction pulls the granulation together to close the defect. Epithelialization is the growth of epithelial cells (skin) over the defect.


Healing by Primary Intention

Surgical wounds that have been sutured or stapled closed heal by primary intention. Epithelial cells close the small gaps in the skin. Granulation will still occur below the surface. No contraction is needed because the surgeon reconnects all layers of the wound.

Healing by Secondary Intention

Full-thickness wounds such as a pressure ulcer or dehisced (opened) surgical wound require granulation, contraction, and epithelialization to occur. These wounds will have a larger scar than those that heal by primary intention and epithelialization requires a larger surface area.

Healing by Tertiary Intention

This type of healing combines secondary and primary intentions. It is reserved for wounds that are infected or have been contaminated with large amounts of debris. The wound is initially left open to heal by secondary intention, allowing for antibiotic therapy to be completed, decreasing infection and bacteria within the wound. Once infection or bacteria load has improved, the wound can then be closed by primary intention.


Author Profile: Christine Kijek, Registered Colorectal Nurse

Christine Kijek

Christine Kijek is a colorectal nurse at Danbury Hospital in Danbury, CT. She has a wealth of knowledge in this field as well as personal experience. HPFY is thrilled that she has been an active participant in the Ostomy Support Group. She has experience working as a coordinator for cancer patients, post-operative care, and home health care for disabled children and adults. And guess what! Christine is also the recipient of the Nurse Exemplar Award. Christine lives in Bethel, CT with her husband Ed. Her children are married and live nearby. She has 4 grandchildren and is known as GiGi. Christine enjoys riding motorcycles and spends many hours gardening. She can often be found onboard a Carnival Cruise ship lounging by the pool.


Disclaimer: All content found on our website, including images, videos, infographics and text were created solely for informational purposes. Our content should never be used for the purpose of diagnosis or treatment of any medical conditions. Content shared on our websites is not meant to be used as a substitute for advice from a certified medical professional. Reliance on the information provided on our website as a basis for patient treatment is solely at your own risk. We urge all our customers to always consult a physician or a certified medical professional before trying or using a new medical product.


HPFY Christine Kijek, RN, BSN, WON

Christine Kijek, RN, BSN, WON

LinkedIn Profile Christine Kijek is a registered nurse with a Bachelor of Science degree in Nursing. She has completed courses for wound and ostomy specialty and has 20 years of experience. She has ...

Continue reading

Trending Articles

Enteral Feeding: The What, When, and How

Shweta Chaubey

When traditional oral intake is not feasible, enteral feeding comes into play. It supports nutritional needs of individuals recovering from an injury or surgery. Dive into this informative article and learn what, when, why, and how of enteral feeding and ensure optimal patient care.

Using the Carpal Solution Carpal Tunnel Wrist Support

Kevin Cleary

Looking for a non-invasive option to manage carpal tunnel symptoms? Experience relief from constant tingling and pain with this Carpal Solution Wrist Support. Read this article to know about the unique features and benefits of this wrist support brace designed to deal with CTS and find why it is one of the most reliable wrist braces available on the market.

Top 5 Best Reviewed Nebulizers of 2023

Kevin Cleary

Need an effective and affordable nebulizer? Look no further, in this article we offer 5 of our best reviewed nebulizers that are loved by our customers. Click to read more and find the perfect nebulizer for all your respiratory needs.

10 Best Overnight Adult Diapers

Shweta Chaubey

Worried about nighttime leaks? Say goodbye to leakage with our ten best overnight adult diapers and wake up refreshed and dry.

Five Best Cervical Traction Devices of 2023

Taikhum Sadiq

Neck pain can wreak havoc on your otherwise healthy life. Traction device improves your cervical health and overall well-being. Read more to find our best cervical traction devices designed to curb the stiffness and discomfort of cervical muscles.