Plausible mechanisms of and techniques to assess ankle joint degeneration following lateral ankle sprains: a narrative review

Lateral ankle sprain (LAS) is the most common lower extremity musculoskeletal injury sustained during daily life and sport. The cascade of events that starts with ligamentous trauma leads to clinical manifestations such as recurrent sprains and giving way episodes, hallmark characteristics of chronic ankle instability (CAI). The sequelae of lateral ankle sprains and CAI appear to contribute to aberrant biomechanics. Combined, joint trauma and aberrant biomechanics appear to directly and/or indirectly play a role in talar cartilage degeneration. Up to 80% of all cases of ankle osteoarthritis (OA) are post-traumatic in nature and common etiologies for ankle post-traumatic osteoarthritis (PTOA) are histories of a single and recurrent ankle sprains. Despite known links between LAS, CAI, and PTOA and evidence demonstrating the burden of LAS and its sequelae, early pathoetiological changes of ankle PTOA and how they can be assessed are poorly understood. Therefore, the purpose of this paper is to review the plausible mechanistic links among LAS and its sequelae of CAI and PTOA as well as review non-surgical techniques that can quantify talar cartilage health. Understanding the pathway from ligamentous ankle injury to ankle PTOA is vital to developing theoretically sound therapeutic interventions aimed at slowing ankle PTOA progression. Further, directly assessing talar cartilage health non-surgically provides opportunities to quantify if current and novel intervention strategies are able to slow the progression of ankle PTOA.