A hypertrophic distal fascicle of the anterior tibiofibular ligament is associated with a high rate of osteochondral lesions of the talus

Purpose: The purpose of this retrospective review was to determine the prevalence of osteochondral lesions (OCLs) of the lateral talar dome in patients with anterior ankle impingement with an associated hypertrophic distal fascicle of the anterior tibio-fibular ligament. Methods: Retrospective chart review identified 40 patients who underwent anterior ankle arthroscopy for the management of anterior ankle impingement. Clinical outcomes assessed included pre- and postoperative foot and ankle outcome score (FAOS), visual analogue scale (VAS), complications, failures, secondary surgical procedures, return-to-work data and return-to-sport data. Results: Thirty-two patients with a mean follow-up time of 29.3 +/- 10.4 months were included. The hypertrophic distal fascicle of the anterior tibio-fibular ligament was hypertrophic in 29 patients (90.6%), with a mean thickness of 2.5 +/- 0.4 mm on MRI. There were 22 OCLs of the lateral talar dome (75.9%) with an associated hypertrophic distal fascicle of the anterior tibio-fibular ligament visualized during arthroscopy. The international cartilage repair society gradings of the lesions included 3 (13.6%) grade I lesions, 15 (68.1%) grade II lesions, 3 (13.6%) grade III lesions, and 1 (4.6%) grade IV lesion. There was a statistically significant improvement in mean FAOS and VAS scores from preoperative to postoperative (p < 0.001). No cases of syndesmotic instability were observed following resection of hypertrophic distal fascicle of the anterior tibio-fibular ligament. Conclusion: This retrospective case series demonstrated that a hypertrophic distal fascicle of the anterior tibio-fibular ligament was associated with an OCL of the lateral talar dome identified during arthroscopic evaluation. In addition, preoperative MRI demonstrated poor sensitivity for the detection of these OCLs. Heightened awareness is warranted for potential lateral talar dome OCLs in patients presenting with anterolateral ankle impingement with a hypertrophic ATiFLdf identified on preoperative MRI in the absence of an associated OCLs.