Anatomy -A cone shaped groove between the talus and calcaneus. The base of the cone faces laterally and the apex is directed medially. Pronation compresses the contents of the sinus tarsi. As the talus adducts, in pronation, the lateral process of the talus rotates forward and impacts the anterior calcaneus. Subjective Complaints Lateral ankle pain.
Pain increases with walking or standing.
Patients are most symptomatic when walking on uneven surfaces. Histories of a long walk on cobblestone streets, uneven hiking trails, etc. Palpate the sinus tarsi while avoiding the lateral ankle ligaments. Pain with palpation of the sinus tarsi. Morton's Neuroma Definition -Perineural fibrosis of the third common digital nerve in the third intermetatarsal space.