Sinus tarsi

Cause, clinical and ultrasound findings

• The causes of sinus tarsi syndrome are not well defined. The condition is associated with oedema and swelling in the space between the calcaneus and talus. Some consider the cause to be cruciate and interosseous ligament injury, while others believe it to result from arthropathy in the adjacent subtalar joints; some regard sinus tarsi syndrome to be a biomechanical problem.

• Ultrasound findings are usually normal, and the diagnosis is determined by a positive response to an anaesthetic block in the region.