Figure 2: Real stress versus stretch curves for a healthy (a) and NF1 (b) skin, regardless of age, gender, race and location, oriented along Langer lines at a 1 Hz frequency during a tensile tests until rupture: healthy patients (light gray symbols) and NF1 patients (dark gray symbols). Average real stress at break regardless of age, gender, race and location (c).*corresponded to p < 0.05.