Scars remain a common patient concern for which numerous treatments are available. One frequently used approach is that of injection therapy. This historically has been done through the use of steroids and, more recently, with a chemotherapy agent such as 5-fluorouracil. These injectional approaches are designed to disrupt how collagen bundles are formed or to disrupt or unbundled those that have formed. There has been usually reserved for the most problematic of scars such as keloids and more severe forms of hypertrophic scars.
Very recently, Botox (botulinum type A) injections have been added to the injectional agent list for scar therapy. Not only have I seen patients who have had their scars injected locally but a few clinical papers in plastic surgery journals have been reported. The logical question is…what is the connection between wrinkles treatments and scar therapy? Does the use of Botox for scar therapy make sense?
As most of the general public is aware, Botox is an anti-wrinkle injection treatment for certain facial areas particularly in the forehead and around the eyes. It works because of its local muscle paralyzing effect, decreasing the presence of dynamic wrinkling. But what does that have to do with what makes scars look bad…or prevent them from ever getting to that point? While Botox has been given some ‘magical properties’ by some, it is not a injection cure-all for anything (and it is being used for a lot of diverse medical problems) and any potential effect must have a biologic basis for its use.
One of the many factors that influences scar outcomes is tension, pulling forces placed on the wound or incisional edges. There are two main factors that cause wound tension. The first factor is how tight is the wound closure, a force that comes primarily from the skin edges themselves. That is a wound influence that the plastic surgeon has some, but not much, control over. Wound suturing techniques help but when tissue as been lost or moved, the closure is going to be under some tension. The body relaxes this tension over time through scar widening and redness. The other tension factor, probably less significant, is the pulling of the tissues from the underlying muscle. This is primarily a potential issue in facial wounds and it has to have the right combination of scar orientation to the direction of the expressive muscle movement action. (scar must be oblique or perpendicular to how the muscle moves) Herein lies the theoretical benefit of Botox scar therapy. If the muscle action is lessened during the early phases of healing, scar widening could theoretically be reduced.
While the use of Botox in scar treatments makes some theoretical sense, its clinical use at this time is far more hopeful than proven. There are numerous factors that influence how a scar will eventually look and limited muscle action around a scar is but just one of them. Such Botox use would have to be done early (within the first few months) and would not have any chance of being effective in more mature scars. But the magical perception of Botox and the understandable anxiety of having a visible scar will likely lead to a lot of useless injection treatments. But hope is eternal and, for the sake of a few hundred dollars, there is no real downside to throwing this injection approach into the alchemy of scar therapies.
Dr. Barry Eppley
Indianapolis, Indiana