Comparative study of the sural flap in 78 patients with a minimum follow-up of 1 year: does pedicle length matter?

The sural flap is widely recognized as an effective method for soft tissue coverage in severe lower limb trauma or sequelae. This retrospective cohort study investigates the impact of vascular pedicle length in reverse sural fasciocutaneous flaps on vascular complications, specifically whether longer pedicles are associated with increased complications.

We included patients with distal third leg and foot soft tissue defects, treated between March 2008 and March 2021, with a minimum follow-up of 1 year. The cohort was divided into two groups based on the location of the flap: those with flaps above the ankle joint (short pedicle) and those below (long pedicle). Patient demographics, comorbidities (e.g., diabetes, peripheral vascular disease, smoking), and the causes of defects (including fractures, ulcers, and degloving injuries) were assessed. The occurrence of complications, including epidermolysis, partial necrosis, and total necrosis, were compared between groups using bivariate linear regression.

A total of 44 patients received flaps above the ankle joint, while 34 had flaps below the ankle joint. Overall, 35% of patients experienced complications: 5% epidermolysis, 20% partial necrosis, and 10% total necrosis. In the short-pedicle group (flaps above the ankle), 13 complications were observed: 3 cases of epidermolysis, 5 of partial necrosis, and 5 of total necrosis. In the long-pedicle group (flaps below the ankle), 15 complications occurred: 1 case of epidermolysis, 11 of partial necrosis, and 3 of total necrosis. Although complication rates were similar between the two groups, a trend toward a higher incidence of partial necrosis was observed in the longer pedicle group. Statistical analysis using bivariate linear regression found no significant difference in complication rates based on pedicle length (p=0.407). For individual complications, there were no statistically significant differences: epidermolysis (p=0.504), total necrosis (p=0.808), and partial necrosis (p=0.098).

Flap rotation points positioned 5-6 cm above the lateral malleolus, with a wide, short pedicle, may reduce vascular complications. For defects beyond the ankle joint, careful surgical planning is crucial, to minimize the risk of partial necrosis and other complications.