RESUMEN
The purposes of this study were to classify anterior talofibular ligament injuries (ATFL), to find out the feasibility of arthroscopic ATFL repair according to injury type and to investigate the diagnostic validity of magnetic resonance imaging (MRI) of ATFL injuries by comparing MRI and arthroscopic findings. The 197 ankles (93 right, 104 left, and 12 bilateral) of 185 patients (90 men and 107 women; mean age, 33.5 years, range: 15-68 years) were treated by arthroscopic modified Broström procedure after a diagnosis of chronic lateral ankle instability. ATFL injuries were classified according to their grade and location (type P: partial rupture, type C1: fibular detachment, type C2: talar detachment, type C3: midsubstance rupture, type C4: absence of ATFL, type C5: os subfibulare). Among the 197 injured ankles, according to ankle arthroscopy, 67 were type P (34%), 28 were type C1 (14%), 13 were type C2 (7%), 29 were type C3 (15%), 26 were type C4 (13%), and 34 were type C5 (17%). The kappa value for the agreement between the arthroscopic findings and MRI findings was also high (0.85; 95% confidence interval, 0.79-0.91). Our results also supported the use of MRI for diagnosing ATFL injuries and showed that it is an informative tool during the preoperative period.