Prevention of surgical scars

Scarring is a natural biological process of wound healing and repair. Scars develop during the maturation phase of wound healing, when production and degradation of new collagen fibres occur. Most scars are pale and flat; however, they can be raised and prominent due to excessive collagen and scar tissue formation. The two main types of abnormal scars are hypertrophic and keloid scars.

Hypertrophic scars are thick scars caused by excess tension on the healing wound. They remain within the boundaries of the wound area and may spontaneously regress over time.

Keloid scars are smooth, hard growths that extend beyond the boundaries of the wound area. They can be uncomfortable, itchy and large. Keloid scars do not regress and may recur after excision.

Note: Designing the skin incision to minimise tension is the most important factor in preventing an abnormal scar.

Risk factors for scars include:

  • improper incision design—a major risk factor for hypertrophic scars
  • darkly pigmented skin (eg African ethnicity)—a major risk factor for keloid scars
  • incisions over the shoulder, chest, upper back or earlobe
  • younger age—the risk of keloid scars peaks between the ages of 10 and 20 years
  • severe acne
  • history of keloid scars
  • family history of abnormal scarring
  • inadequate blood supply to the wound
  • inappropriate surgical technique.

Intraoperative procedures to minimise scarring include using aseptic technique, minimising skin tension, accurate skin edge approximation and atraumatic tissue handling.

Surgical wound management to prevent scars includes:

  • using silicone gel sheets or silicone oil-based cream on healed wounds (not open wounds) for 1 month in patients at high risk of scarring
  • removing sutures or clips at the appropriate time (see Overview of management of surgical wounds)
  • applying skin tape (eg Micropore) across the incision line to reduce tension for 3 months following removal of sutures or clips.

One week after surgery, the tensile strength across the incision site is only 3% of normal (uninterrupted) skin. This increases to 20% after 3 weeks, and reaches 80% by 3 months.