Evaluation of the Prevalence of Os Trigonum and Talus Osteochondral Lesions in Ankle Magnetic Resonance Imaging of Patients With Ankle Impingement Syndrome.

The prevalence of os trigonum and osteochondral lesions of talus (OCLT) have been presented in different prevalences among different groups in the literature for the patients with ankle impingement syndrome. Our main objective in the study was to determine the possible relationship between the impingement syndrome and the prevalence of os trigonum and OCLT in specific groups. The presence of anterior ankle impingement syndrome (AAIS), posterior ankle impingement syndrome (PAIS), os trigonum, OCLT, and the location of OCLT were evaluated in a blinded manner on magnetic resonance imaging from patients clinically considered to be diagnosed with ankle impingement syndrome from January 2014 to July 2017. The patients were separated into specific groups according to the confirmation of their clinical diagnosis of ankle impingement syndrome on magnetic resonance imaging . A total of 333 patients were included. The prevalence of os trigonum was found to be 1.3% in patients with PAIS(-) AAIS(+), 7.7% in patients with PAIS(-) AAIS(-), 63.3% in patients with PAIS(+) AAIS(-), and 81.1% in patients with PAIS(+) AAIS(+) (p < .001). The prevalence of OCLT was found to be 41.3% in patients with PAIS(-) AAIS(+), 23.1% in patients with PAIS(-) AAIS(-), 18.3% in patients with PAIS(+) AAIS(-), and 27% in patients with PAIS(+) AAIS(+) (p= .005). Our study showed that, for patients with isolated PAIS and AAIS combined with PAIS, the prevalence of os trigonum was 63.3% and 81.1%, respectively, which is more common than previously reported. For patients with isolated AAIS and PAIS, the prevalence of OCLT was 41.3% and 18.3%, respectively. Of the OCLTs combined with ankle impingement syndromes, 87.1% were medially located.