The role of ankle arthroscopy in the treatment strategies of osteochondritis dissecans lesions of the talus.

Thirty-six cases of osteochondritis dissecans (OD) of the talus were diagnosed among 413 ankle arthroscopies performed within a period of six years. In 52.8% of the cases the OD was found on the medial and in 41.7% on the lateral talus. 53.3% of the lateral OD presented stage III and IV lesions while only 26.3% of the medial OD were to be graded stage III and IV. Patients with grade I and II lesions had mostly excellent outcome scores between 90 and 100. However, four patients with medial OD at less severe stages who were treated surgically, showed a particularly unfavorable outcome with scores between 11 and 36. All these patients needed either ankle arthrodesis or total ankle joint replacement. For stage II and III medial lesions, our experience has led to a more conservative approach due to the unfavorable outcome of surgical treatment observed in these patients. Despite the usefulness of MRI in the diagnosis of OD of the talus, arthroscopy has been proven to represent a very helpful diagnostic tool in assessing extent and in particular stability and integrity of the osteochondritic lesion. Apart from enabling the various minimally invasive surgical treatment options, ankle arthroscopy should be performed in all patients with OD of the talus in order to help define the treatment strategy and avoid unnecessary surgery on stable lesions.