Subungual exostosis

Bone stalk containing cartilaginous cap that blends into overlying fibrous connective tissue

Chondrocytes set within abundant hyaline cartilage matrix; eosinophilic cytoplasm; round-ovoid nuclei with small nucleoli, occasional binucleation, mild pleomorphism, and inconspicuous mitotic activity

Fibroblasts are spindle-stellate and set within abundant collagenous stroma; eosinophilic cytoplasm with delicate tapering processes; monomorphic ovoid nuclei with inconspicuous mitotic activity

Predisposition for the "great" toe

Bone stalk containing cartilaginous cap that blends into overlying fibrous connective tissue

Chondrocytes set within abundant hyaline matrix; eosinophilic cytoplasm; round-ovoid nuclei with small nucleoli, occasional binucleation, mild pleomorphism, and inconspicuous mitotic activity

Fibroblasts are spindle-stellate and set within abundant collagenous stroma; eosinophilic cytoplasm with delicate tapering processes; monomorphic ovoid nuclei with inconspicuous mitotic activity

Bone stalk containing discontinuous cartilaginous cap that blends into overlying fibrous connective tissue

Chondrocytes set within abundant hyaline matrix; eosinophilic cytoplasm; round-ovoid nuclei with small nucleoli, occasional binucleation, mild pleomorphism, and inconspicuous mitotic activity

Fibroblasts are spindle-stellate and set within collagenous stroma; eosinophilic cytoplasm with delicate tapering processes; ovoid nuclei with small nucleoli, mild atypia and inconspicuous mitotic activity