Percutaneous Fasciotomies versus Traditional Keystone Flap: Evaluating Tension in Complex Wound Closure

The keystone flap is a popular reconstructive option for closure of cutaneous defects. Traditionally, this is a perforator-based fasciocutaneous advancement flap that uses both skin incision and fascial release. We propose a limited skin incision technique that utilizes percutaneous fasciotomies to accomplish wound closure.

Fresh cadavers were used to compare closure techniques in traditional keystone flaps versus percutaneous fasciotomy technique. Each cadaver served as its own control; traditional keystone flaps were performed on the right side, experimental fasciotomy technique on the left. Bilateral large wound defects were created in 6 anatomical locations: anterior leg, lateral thigh, buttocks, lower back, upper back, and brachium. These defects could not be closed primarily, as defined by tension >25 Newtons or rupture of a 2-0 nylon suture. Twenty-four flaps were created. Keystone flaps were designed on the right side using a 1:1 ratio of defect size to flap width, incorporating both skin and fascial incisions. On the left, percutaneous fasciotomies were drawn using a mirror template and performed through two small access incisions. If wound closure could not be achieved by fasciotomy alone, additional incisional release was performed incrementally until closure was obtained. The tension of closure was measured using a PESOLA (10 N, 25 N) tensiometer (Chandelle, Switzerland), and the average of three recordings was used. Tension was measured at various stages of flap development including: keystone flap (posterior fascia, lateral fascia, V-Y skin closure) versus percutaneous fasciotomy (posterior fascia, lateral fascia, posterior skin). Statistical analysis was completed using Wilcoxon Signed Rank test to compare the two techniques.

Lower tension closures were achieved through release of the posterior fascia in the traditional keystone flap compared to the percutaneous fasciotomy technique. These differences in tension were statistically significant (P < 0.001). Release of the lateral fascia in the keystone flap resulted in a similar decrease in tension (P < 0.01). The percentage drop in tension before and after each particular intervention was measured. No significant difference was found between these 2 groups.

When compared with the traditional keystone flap, the percutaneous fasciotomy technique displayed higher tensions in closure. However, this technique showed the ability to close defects in certain locations of the body without excessive tension and should be considered as an option in soft-tissue reconstruction.