In Berndt-Harty OCD lesions, which type is located on the medial talar dome and often difficult to access surgically?

• A. Type I
• B. Type II
• C. Type III
• D. Type IV

Answer: (C)

Berndt-Harty classification describes how an osteochondral lesion of the talus progresses from a simple cartilage/subchondral bone insult to a detached, sometimes displaced fragment. The key idea you’re being tested is that the more detached and displaced the lesion, the more challenging the surgical approach tends to be, especially when the lesion sits in a hard-to-reach area.

Type III is a completely detached osteochondral fragment that remains within its crater on the talar dome. When this sits on the medial aspect of the talar dome, access is particularly difficult because the medial surface is less forgiving to maneuver and the crater can be deep and tucked under surrounding bone and soft tissue. This combination—complete detachment plus a medially located, hard-to-reach crater—drives the surgical challenge and often dictates a approach that aims to address stability and restore congruity, such as fixation of the fragment or other reconstructive steps.

In contrast, Type I is a small compression of subchondral bone with an intact cartilage surface, usually easier to access; Type II involves a partially detached fragment, which is typically more accessible than a fully detached one; Type IV describes a displaced fragment that has moved and may be addressed with different strategies, depending on exact position.