Current Definitions of Failure in Lateral Ankle Instability Surgery: A Systematic Review

Background: "Failure" is a term that is frequently used to describe an unfavorable outcome for patients who undergo surgical treatment for lateral ankle instability (LAI). A standard definition of failure for the surgical treatment of ankle instability has not been established by clinicians and researchers. Purpose: To identify the definitions of ankle instability treatment failure that are currently in the literature and to work toward the standardization of the definition. Study Design: Systematic review; Level of evidence, 4. Methods: A systematic search of MEDLINE, SPORTDiscus, CINAHL, Embase, and Web of Science was conducted to identify clinical studies that included patients who underwent surgical treatment for LAI and included information about surgical failure. Studies with level of evidence 1 to 4 were included in this review. Animal studies, biomechanical studies, cadaveric studies, review articles, and expert opinions were excluded. The included studies were then reviewed for definitions of failure of any surgical procedure that was performed to correct LAI. Results: Of the 1200 studies found, 3.5% (42/1200) published between 1984 and 2021 met the inclusion criteria and were analyzed. After reviewing the data, we found numerous definitions were reported in the literature for LAI surgical failure. The most common was recurrent instability (40% [17/42]), followed by rerupture (19% [8/42]). For the original surgical procedure, the anatomic Brostrom-Gould technique was used most frequently (57% [24/42]). The failure rate of the Brostrom-Gould technique ranged from 1.1% to 45.2% depending on the definition of failure. Conclusion: There were multiple definitions of failure for the surgical treatment of LAI, which is one of the reasons why the rate of failure can vary greatly. The literature would benefit greatly from the standardization of the definition of ankle instability treatment failure. This definition should include specific, objective physical examination findings that eliminate the ambiguity surrounding failure.