Normal Foot Xray
Xrays are basic investigations for orthopedic problems. To find the abnormal one must have an idea of normal.
This is how a normal foot x-ray looks like. The present image shows an anteroposterior and oblique view x-ray of the left foot.
On the left side of the plate, there is an oblique view x-ray of the foot. On the right side, there is anteroposterior view.
Xray of the foot is ordered in various ailments of the foot including trauma. Anteroposterior and oblique views are most common views that are ordered on the foot. Anteroposterior views are also called dorsoplantar views.
Another view that is commonly done in addition to these views is lateral view.
Here is a video that demonstrates how foot x-ray views are taken. In the video x-ray of the right foot is being done.
What to Look For in Normal Foot Xray?
The normal foot can be divided into three different regions
- Forefoot – It consists of phalanges[toes] and metatarsals
- Midfoot – It has navicular, cuboid and three cuneiforms namely medial, intermediate and lateral
- Hindfoot: Talus and Calcaneus
Bones of the midfoot and hindfoot are referred to as the tarsal bones
Following x-ray shows the location of these bones on x-ray.
The anteroposterior or dorsoplantar view is very good for visualizing medial elements – first and second metatarsal bones, medial and intermediate cuneiforms and medial articulation of the Lisfranc joint.
In a normal anteroposterior foot x-ray, interphalangeal joints are obscured but metatarsophalangeal joints are well seen and each joint should be checked. All the parts of ray – metatarsal and phalanges are well aligned.
Sesamoid bones in the first toe is a normal finding.
Head, neck, and shaft of metatarsals are clearly visualized but bases blur.
The Lisfranc joint is another name for the tarsometatarsal joint. In this joint, first, second, and third cuneiforms, and the cuboid, articulate with the bases of the metatarsal bones. The bones are connected by dorsal, plantar, and interosseous ligaments.
Lisfranc joint is very important for stability and subtle injury if missed, can lead to problems. A normal Lisfranc joint is characterized by
– Medial borders of the second metatarsal and intermediate cuneiform should be in line on anteroposterior x-ray.
– Medial borders of the 3rd metatarsal and lateral cuneiform should line up on the oblique view.
Oblique View enables to clearly visualize 3rd, 4th and 5th metatarsals, lateral cuneiform, navicular and cuboid.
Phalanges and interphalangeal joints are better visualized in oblique x-rays. The base of fifth metatarsal [site for Jones’s fracture] and tarsometatarsal alignment should be checked. As noted in anteroposterior x-ray, for tarsometatarsal joints to be normal medial margins of tarsal bone and respective metatarsal should be aligned. Finally, the lateral tarsals and calcaneum should be analyzed. Oblique view x-ray of the foot also gives an opportunity to have second look at the navicular bone.