2nd metatarsal head osteonecrosis or osteochondral fracture
Mottled sclerosis and lucency
flattening of head
bone marrow edema
Smillie classification
Stage I: epiphyseal fissure surrounded by sclerosis
Stage II: mild subchondral collapse
Stage III: prominent medial and lateral projection of MT head
Stage IV: MT head projection fracture, central area of collapse
Stage V: extensive articular surface collapse, osteoarthritis