Although ankle sprains are common in older adolescent patients and young adults, isolated ankle sprains are not very common in younger children and in preadolescent patients. The ATFL can be palpated just inferior and anterior to the distal most aspect of the lateral malleolus. Review ATFL location. Because the patient in this case has point tenderness in an area other than over the ATFL, he has therefore not sustained a typical ankle sprain. In comparison to these lateral ligaments, the medial, deltoid ligament has a fair degree of elasticity and is much more resistant to tears.
Most injuries also occur while the ankle joint is in plantar flexion rather than in dorsiflexion.
Anatomically, the talar dome is wedge-shaped, with the anterior aspect of the talus being wider than the posterior aspect. However during plantar flexion, the narrower, posterior aspect of the talus becomes engaged in the ankle mortise. Review joint space diagram. Note the obvious widening of the joint space during plantar flexion on the left compared to dorsiflexion on the right. Thus, with this understanding of the articulation of the talus within the mortise, it is not surprising that most ankle injuries occur while the ankle is in plantar flexion, rather than in dorsiflexion.