Dr. Robert Donatelli author of “The Biomechanics of the Foot and Ankle” described the following phases of gait during stance: heel contact, weight acceptance, midstance, push-off and propulsion, and toe-off. The plantar fascia prevents foot collapse thanks to its anatomical orientation and tensile strength; it is subdivided into central, medial, and lateral components as it gradually widens and courses distally. The central, or major, component of the plantar aponeurosis is the largest, thickest, and strongest. It is triangular and divides into five bands at the midmetatarsal level. Plantar fascia pain results from excessive traction forces applied to the calcaneus. Every time that you’ll perform a plantar aponeurosis ultrasound examination, don’t forget to think at the foot biomechanics and releate dysfunction to plantar fascia abnormalities. Overpronation or underpronation foot abnormalities? Wath’s best for plantar aponeurosis study? Mri or ultrasound exam? I usually perform both. Take a look at the images below and see why.Sagittal dynamic ultrasound scan of a runner with degenerative rupture of the plantar aponeurosis mayor component; it is evident the irregularity of cortical bone insertion.