A nail dystrophy that typically occurs on the great toenails more commonly in women, and is due to trauma to the nail matrix. Characteristic clinical features include stacking of multiple generations of nail plates, slow nail growth, thickened, discolored, separated nail plate, lack of a cuticle and +/- pain. This condition is often misdiagnosed as toenail fungus and patients often present frustrated and misguided. Treatment depends on stage of disease.