 Abstract nail psoriasis occurs in approximately two out of every three psoriasis patients. It affects both fingernails and toenails, as well as causing severe destruction of the nail beds. Additionally, it is often associated with a more severe course of the disease and the development of psoriatic arthritis. To measure the severity of nail psoriasis, experts manually grade the condition of each nail of the patient, resulting in a maximum score of 80 points for all nails of the hands. However, this method is impractical when multiple nails are involved or when the patient's condition changes over time. In this study, we developed a computerized version of the nail psoriasis severity index, NAPSI, called modified NAPSI, MNAPSI. First, we took photographs of the hands of patients with psoriasis, psoriatic arthritis, and rheumatoid arthritis. Then, we collected and annotated the MNAPSI scores of 1154 nail photos. Afterwards, we used an automated keypoint detection system to extract individual nails. This article was authored by Lucas Four, Pauline Fenzel, Filippo Fagni, and others. We are article.tv, links in the description below.