Talar beak sign
The talar beak sign is seen in cases of tarsal coalition, and refers to a superior projection of the distal aspect of the talus. It is most frequently encountered in talocalcaneal coalition. It is thought to result from abnormal biomechanic stresses at the talonavicular joint.
It needs to be distinguished from:
- an osteophyte due to degenerative change at the talonavicular joint
- the talar ridge found more proximally at the site of insertion of the ankle capsule1; the normal talar ridge is several millimeters high and has a straight or slightly convex, graded slope proximally, and a straight, sharp margin distally 2
- 1. Crim JR, Kjeldsberg KM. Radiographic diagnosis of tarsal coalition. AJR Am J Roentgenol. 2004;182 (2): 323-8. AJR Am J Roentgenol (full text) - Pubmed citation
- 2. Resnick D. Talar ridges, osteophytes, and beaks: a radiologic commentary. Radiology. 1984;151 (2): 329-32. Radiology (abstract) - Pubmed citation
- 3. Crim JR, Kjeldsberg KM. Radiographic diagnosis of tarsal coalition. AJR Am J Roentgenol. 2004;182 (2): 323-8. AJR Am J Roentgenol (full text) - Pubmed citation