Imaging description

Weight bearing lateral radiographs may demonstrate bony spurs and capsular distension at the anterior aspect of the tibiotalar joint. CT can further characterize the location and size of the spurs. Soft tissue changes associated with anterior impingement such as thickening in the anterior recess can be detected with ultrasound and MRI.

Importance

Anterior impingement is considered as a common cause of chronic anterior ankle pain among athletes especially ballet dancers and soccer players. Bony spurs at the anterior ankle joint (Figure 66.1) are a component of this condition, but not all the spurs are associated with symptoms. Arthroscopic studies reveal hypertrophic synovium or scar tissue is compressed between the spurs during dorsiflexion. This compression is believed to cause pain. Therefore, these imaging findings need to be correlated with symptoms and physical findings. Anterior tibial spurs occur commonly lateral to the midline, whereas anterior talar spurs develop commonly in the medial part. Lateral radiographs can detect anterolateral osteophytes. Oblique radiographs may be necessary to detect anteromedial osteophytes (Figure 66.2).