This is the largest single MRI series of talar osteochondral lesions, reviewing 428 lesions in 424 patients. The authors introduce a reproducible nine-zone (3×3) grid on the talar dome to standardize how lesion location is described. The question: where do these lesions actually sit, and how does morphology vary by location?
When you read an ankle MRI showing a talar osteochondral lesion, expect it at the medial or lateral equator, not the classic posteromedial/anterolateral corners. That old teaching describes lesion morphology (deep cup-shaped medial, shallow wafer-shaped lateral) more than true AP position. This paper shows the AP center of the dome carries about 80% of lesions.
The practical payoff is surgical access. Zone 4 medial equatorial lesions dominate at 53%, which explains why medial malleolar osteotomy or an anteromedial approach is so frequently required. Size and depth matter for treatment: medial lesions run larger and deeper (93 mm², 6.3 mm) than lateral ones, pushing decision-making toward cartilage restoration rather than simple debridement.
One trap worth remembering: a medial lesion can hide beneath intact-appearing cartilage on MRI, so map the location before arthroscopy and probe that zone deliberately rather than surveying the whole dome.
This is the largest single MRI series of talar osteochondral lesions, reviewing 428 lesions in 424 patients. The authors introduce a reproducible nine-zone (3×3) grid on the talar dome to standardize how lesion location is described. The question: where do these lesions actually sit, and how does morphology vary by location?
When you read an ankle MRI showing a talar osteochondral lesion, expect it at the medial or lateral equator, not the classic posteromedial/anterolateral corners. That old teaching describes lesion morphology (deep cup-shaped medial, shallow wafer-shaped lateral) more than true AP position. This paper shows the AP center of the dome carries about 80% of lesions.
The practical payoff is surgical access. Zone 4 medial equatorial lesions dominate at 53%, which explains why medial malleolar osteotomy or an anteromedial approach is so frequently required. Size and depth matter for treatment: medial lesions run larger and deeper (93 mm², 6.3 mm) than lateral ones, pushing decision-making toward cartilage restoration rather than simple debridement.
One trap worth remembering: a medial lesion can hide beneath intact-appearing cartilage on MRI, so map the location before arthroscopy and probe that zone deliberately rather than surveying the whole dome.