A Notta nodule Diagnosis of a<unk>  thumb is solely made by these clinical observations and further classified into four stages: Stage Observations I A Notta nodule is present, but no<unk> ing is observed in the IPJ. II<unk> ing is observed during active extension of the IPJ. III Active extension of the IPJ is not possible and<unk> ing is observed during passive extension of the IPJ. IV Passive extension of the IPJ is not possible. (There is a fixed flexion deformity.)
Congenital trigger thumb
Congenital clasped thumb
Adducted thumb syndrome
Mallet finger
Blue toe syndrome
Congenital contractural arachnodactyly
Hypothenar hammer syndrome
Radial dysplasia