Understanding Chronic Ankle Instability – model rich, data poor

Ankle sprains are common sports injuries. Although often perceived as innocuous, large proportions of patients develop a cluster of persistent symptoms, termed chronic ankle instability(CAI). In 1965, Freeman1 first described a clinical paradox whereby poor recovery after ankle sprain (characterised by feelings of ‘giving way’) was reported in both the presence and absence of mechanical instability (MI).Since then, researchers have tried to explain this anomaly using original research, theoretical frameworks and multicomponent aetiological models for CAI. In this editorial, we discuss perennial and fundamental shortcomings in the evidence base, that continue to limit our understanding of CAI causation.