Feasibility of Arthroscopic Anterior Talofibular Ligament Repair and Comparison Between Arthroscopic and MR Findings for Anterior Talofibular Ligament Injuries

CATEGORY: Arthroscopy; Ankle; Arthroscopy INTRODUCTION/PURPOSE: The Modified Broström Operation (MBO) has been frequently used to treat chronic lateral ankle instability. Recent studies of arthroscopic anterior talofibular ligament (ATFL) repair found that if the ligament is detached at the fibular attachment or there is sufficient remnant tissue, it can be directly repaired using suture anchors. In this study, ATFL injuries were classified and the feasibility of arthroscopic ATFL repair according to injury type was determined. The diagnostic validity of magnetic resonance imaging (MRI) of ATFL injuries was investigated by comparing MRI and arthroscopic findings. METHODS: The 197 ankles (93 right, 104 left; 12 bilateral) of 185 patients (90 men and 107 women; mean age, 33.5 years, range: 15-68 years) were treated between September 2015 and October 2019. All patients underwent arthroscopic MBO after a diagnosis of chronic lateral ankle instability. ATFL injuries were classified according to their grade and arthroscopically determined location (type 2: partial rupture, type 3A: fibular detachment, type 3B: talar detachment, type 3C: midsubstance rupture, type 3D: absence of ATFL, type 3E: os subfibulare). Two musculoskeletal radiologists blinded to the surgical findings evaluated all of the ankle injuries and classified them as described above. An oblique-coronal MRI sequence was used to improve diagnostic accuracy. RESULTS: The kappa value for interobserver reliability was 0.82 (95% confidence interval [CI], 0.76-0.88), indicating excellent interobserver reliability. The kappa value for the agreement between the arthroscopic findings and MRI findings was also high (0.85; 95% CI, 0.79-0.91). Among the 197 injured ankles, according to ankle arthroscopy, 67 were type 2 (34%), 28 were type 3A (14%), 13 were type 3B (7%), 29 were type 3C (15%), 26 were type 3D (13%), and 34 were type 3E (17%). CONCLUSION: In this study, arthroscopic ATFL repair was feasible in ~14% of ATFL injuries related to chronic lateral ankle instability. The ATFL classification system proposed herein could help surgeons to determine treatment options before surgery in patients with ATFL injuries, and even evaluate acute injury. Our results also supported the use of MRI for diagnosing ATFL injuries and showed that it is an informative tool during the preoperative period.