Morphology of tibiotalar osteophytes in anterior ankle impingement

The purpose of this study was to document radiographic trends in the size and location of osteophytes occurring in patients who have undergone surgical treatment of bony anterior ankle impingement. All patients over a period of 31 months who had undergone surgical excision of anterior ankle osteophytes were identified. 9 patients (10 ankles) in whom preoperative CT scans were available were selected as the study group. This group was retrospectively reviewed in terms of basic preoperative characteristics (age, sex, symptomatology, sports history, systemic disease, passive dorsiflexion). Osteophyte size was measured on plain lateral radiographs, and axial CT images were used to determine both tibial and talar osteophyte location by referencing them to the midline of the talar dome. 95% confidence intervals demonstrated that the talar spur peak lies medial to the midline, the tibial spur peak lies lateral to the midline, and the spurs typically do not overlap each other. Further, the tibial spur is wider than the talar spur, and the talar spur usually protrudes medially off the medial edge of the talar neck. Thus, there is evidence that anterior tibiotalar osteophytes may have a relatively consistent pattern of formation, with the talar spur occurring on the medial aspect of the talar neck, and the tibial spur peaking lateral to the midline.This information, if substantiated with additional patients, may provide insight into the pathophysiology of anterior ankle impingement, as well as facilitate the open and arthroscopic approaches toward resection of these lesions.