The angle of the longitudinal arch is one of the angles drawn on the weightbearing lateral foot radiograph. The angle is formed between the calcaneal inclination axis and a line drawn along the inferior edge of the 5th metatarsal.
The normal angle is 150-170°.
In pes cavus, as the height of the longitudinal arch increases, the calcaneal inclination angle increases. The obtuse angle between the calcaneal inclination axis and the 5th metatarsal decreases below 150°.
In pes planus, the angle of the longitudinal arch increases such that the lines become parallel and the angle exceeds 170°.
Related Radiopaedia articles
Lower limb radiography
- standard foot radiograph series
- weightbearing foot radiograph series
- special foot views