Ankle Traction During MRI of Talar Dome Osteochondral Lesions.

OBJECTIVE: The objective of our study was to assess the impact of axial traction during MRI of talar dome osteochondral lesions using a small-FOV coil.

SUBJECTS AND METHODS: A prospective study of 33 patients undergoing high-resolution MRI of the ankle using a microscopy coil with and without axial traction was performed. Two radiologists independently measured the tibiotalar joint space width and semiquantitatively graded intraarticular joint fluid dispersion, cartilage surface visibility of the osteochondral lesion, and cartilage surface visibility elsewhere in the tibiotalar joint before and after traction. Patients were instructed to report any discomfort during ankle traction.

RESULTS: None of the patients reported discomfort or other symptoms during ankle traction. The tibiotalar joint space significantly increased (increase in cartilage-cartilage distance, 0.5-0.7 mm; all, p < 0.05) after traction compared with before traction. The degree of intraarticular joint fluid dispersion and the cartilage surface visibility at the osteochondral lesion and elsewhere in the tibiotalar joint improved after traction (all, p < 0.05).

CONCLUSION: Traction MRI of the ankle is safe and technically feasible. This study is the first to date to investigate the effect of ankle traction on the MRI assessment of talar dome osteochondral lesions. Traction improves cartilage surface visibility of talar dome osteochondral lesions.