Proposed Classification of Syndesmotic Soft Tissue Impingement and Its Association With Lateral Talar Cartilage Lesions

Abstract

Background: Syndesmotic impingement syndrome has been described to explain persistent lateral or anterolateral ankle pain. This condition is thought to often result from a rotational ankle injury. This study aimed to identify the type of syndesmotic impingement tissue according to arthroscopic and histologic findings and to analyze its association with lateral talar cartilage lesions.

Methods: This retrospective study included 107 ankles in 105 patients who underwent arthroscopic surgery for syndesmotic impingement syndrome from January 2017 to August 2019. Histologic findings of biopsied impingement tissue were obtained in 59 ankles (55.1%) and compared with gross findings on arthroscopy. Cartilage lesions were evaluated using the International Cartilage Repair Society grading system. Risk factors associated with lateral talar cartilage injury were evaluated using multivariate logistic regression analysis.

Results: Based on the histologic results, the most common pathology was fibrosis (24 ankles [22.4%]), followed by fatty degeneration (23 ankles [21.5%]), synovial hyperplasia (8 ankles [7.5%]), and inflammatory synovium (4 ankles [3.7%]). Interclass correlation coefficient was 0.841 (P = .001) between histologic results and arthroscopic findings. Patients with fibrotic impingement tissue had on average a significantly longer duration of symptoms (12 vs 48 months, P = .021). A lateral talar dome cartilage lesion was detected in 25 ankles (23.4%). Fibrotic impingement tissue was the only factor significantly associated with lateral talar dome lesion on multivariate logistic regression analysis (odds ratio 10.04; 95% CI 1.84-54.9; P = .008).

Conclusion: Syndesmotic impingement with fibrotic tissue was often associated with cartilage lesions at the lateral talar dome. Patients with prolonged anterolateral or lateral ankle pain after a rotational ankle injury warrant careful assessment for possible syndesmotic impingement by fibrotic tissue and associated lateral talar cartilage injury.