Ankle still painful weeks after an inversion injury? Consider Sinus Tarsi Syndrome
Here is another tricky clinical condition occurring around the ankle, and often presenting as non-resolving pain post ankle inversion injury.
The Sinus Tarsi syndrome
Sinus tarsi syndrome (STS) was first described in 1958 by O’Connor in his paper entitled “Sinus tarsi syndrome: A clinical entity”. Sinus tarsi syndrome is characterized by pain over the lateral aspect of the ankle (in the region of the sinus tarsi) and instability of the rearfoot, especially when walking on uneven surfaces. This syndrome may occur secondary to chronic overload in an athlete who pathologically overpronated, but more commonly is one of the many sequalae of ankle inversion injury.
Anatomy and Pathomechanics
Also known as the talocalcaneal sinus, the sinus tarsi is the anatomical space between the inferior neck of the and the superior aspect of the distal calcaneus. See image below.
"This space is continuous with the tarsal canal, a funnel shape space extending medially to a small opening posterior to the sustentaculum tali"
(Klausner and McKeigue 2000).
The ankle, with the sinus tarsi between the talus and calcaneus, and the ligaments in the sinus
The sinus tarsi is occupied by a neurovascular bundle, fatty tissue, and interosseus talocalcaneal ligament, cervical ligament and the inferior attachment of the extensor retinaculum. These ligaments are supplied by the tarsal canal artery, a branch of the posterior tibial artery.
Director of Bartold Clinical