X-ray of flat feet
Flat feet is a postural deformity in which the arches of the foot collapse, with the entire sole of the foot coming into complete or near-complete contact with the ground.
Contents
Planning
Flat feet can be diagnosed clinically, but projectional radiography ("X-ray") is helpful in uncertain cases. It can be used for severity grading, although this has little implication for treatment options.[note 1]
Diagnosis
On X-ray, flat feet can be diagnosed and graded by several measures, the most important in adults being the talonavicular coverage angle, the calcaneal pitch, and the talar-1st metatarsal angle (Meary's angle).[1] The talonavicular coverage angle is abnormally laterally rotated in flat feet.[1] It is normally up to 7 degrees laterally rotated, so a greater rotation indicates flat feet.[1] Radiographies generally need to be taken on weightbearing feet in order to detect misalignment.[2]
- Talonavicular coverage angle.jpg
Dorsoplantar projectional radiograph of the foot showing the measurement of the talonavicular coverage angle.
- Calcaneal pitch.jpg
Weight-bearing lateral X-ray showing the measurement of calcaneal pitch, which is an angle of the calcaneus and the inferior aspect of the foot, with different sources giving different reference points.[note 2] A calcaneal pitch of less than 17° or 18° indicates flat feet.[1]
- Talar-1st metatarsal angle (Meary's angle).jpg
Same lateral X-ray showing the measurement of Meary's angle, which is the angle between the long axis of the talus and first metatarsal bone.[1] An angle greater than 4° convex downward is considered a flat foot.[1]
Report
Presence or absence of flat feet. To put in simpler words, an abnormally laterally rotated talonavicular coverage angle can be described as "laterally pointed navicular bone", and an abnormally decreased calcaneal pitch and abnormally downward-convex Meary's angle can be described as "fallen arch".
Upon request, severity can be given (Meary's angle angle 15° - 30° is considered "moderate" flat foot, and greater than 30° is considered "severe" flat foot.[1]), otherwise it is not relevant.[note 1]
Notes
- ↑ 1.0 1.1 Indications for non-surgical treatment is based on pain:
- . Flatfeet. Mayo Clinic. Retrieved on 2018-07-04.
- Vulcano, Ettore; Deland, Jonathan T.; Ellis, Scott J. (2013). "Approach and treatment of the adult acquired flatfoot deformity
- . Flatfoot Surgical Correction. American Orthopaedic Foot & Ankle Society. Retrieved on 2018-07-04.
- ↑ Detailed explanations and references are located in the Calcaneal pitch article.
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 . Pes Planus. University of Washington, Department of Radiology. Last modified: 2016/08/14
- ↑ Dan J Bell and Yuranga Weerakkody. Pes planus. Radiopaedia. Retrieved on 2018-03-01.
