Congenital malalignment of the big toe nail is based on a lateral deviation of the nail plate. This longitudinal axis shift is due to a deviation of the nail matrix, possibly caused by increased traction of the hypertrophic extensor tendon of the hallux. Congenital malalignment of the big toe nail is typically present at birth. Ingrown toenails and onychogryphosis are among the most common complications. Depending on the degree of deviation, conservative or surgical treatment may be recommended.