ORIGINAL ARTICLES Treatment of Ingrown Toenail with a Shape Memory Alloy Device Hasan Onur Arik, MD* Mehmet Arican, MD* Volkan Gunes, MD† Ozkan Kose, MD, MSc, FEBOT‡ Background: We sought to report the clinical results of a new conservative treatment modality that uses a shape memory alloy device in patients with ingrown toenail. Methods: A retrospective review was performed on 41 patients with ingrown toenail treated with the K-D device (S&C Biotech, Seoul, South Korea) between April 2013 and July 2014. Recurrence rate, cosmetic results, pain during the treatment period, and patient satisfaction were the major outcome measures. Results: Patients were followed for at least 6 months (mean 6 SD, 8.6 6 2.1 months; range, 6–12 months). Recurrence was seen in eight patients (19.5%). Mean time to recurrence was 6.2 months (range, 3–10 months). Thirty-one patients (75.6%) were satisfied with the treatment. Thirty-five patients (85.4%) rated the application and treatment period as painless, and the remaining six (14.6%) noted pain particularly during shoe wearing. Thirty-one patients (75.6%) rated the cosmetic results as ‘‘excellent, ’’ four (9.8%) as ‘‘acceptable,’’ and six (14.6%) as ‘‘poor. ’’ Satisfaction with the treatment, the cosmetic results, and pain were significantly worse in patients with recurrence (P ¼ .0001 for all). All of the patients returned to their work immediately after application of the device. No complications occurred. Conclusions: The K-D device is a safe and effective treatment method for ingrown toenail. Although the recurrence rate is higher than for surgical treatment methods, the K-D device is a practical and painless method that provides immediate return to work and daily activities and excellent or acceptable cosmesis in most patients. (J Am Podiatr Med Assoc 106(4): 252-256, 2016) Ingrown toenail, or onychocryptosis, is a commonly encountered foot problem in routine orthopedic practice that causes pain, discharge, swelling, undesir- able foot odor, and difficulty in shoe wear and daily activities. 1 Several treatment methods, both conserva- tive and surgical, have been described to date. However, certain disadvantages have been identified in each of these methods, such as recurrence, infection, permanent disfigurement of the natural appearance of the nail, and a considerable period of restriction of daily activities during the healing process. 2 Therefore, research into alternative treatment modalities that eliminate these disadvantages is ongoing. Recently, a new conservative treatment method was introduced that used a device made of shape memory alloy, the K-D device (S&C Biotech, Seoul, South Korea). Initial reported clinical results were promising, with a low recurrence rate, high patient satisfaction, and few minor complications. 1 Howev- er, few studies have evaluated the clinical efficacy of this new modality in the current literature. 3-7 The purpose of this study was to present our experience with this novel device and report the results of treatment in a prospectively followed series of patients with ingrown toenail. Materials and Methods We retrospectively reviewed 41 prospectively fol- lowed patients with ingrown toenail who were treated *Department of Orthopaedics and Traumatology, Yozgat State Hospital, Yozgat, Turkey. †Department of Orthopaedics and Traumatology, Rize Kackar State Hospital, Rize, Turkey. ‡Department of Orthopaedics and Traumatology, Antalya Education and Research Hospital, Antalya, Turkey. Corresponding author: Hasan Onur Arik, Department of Orthopaedics and Traumatology, Yozgat State Hospital, Centrum/Yozgat City, Yozgat, 66000, Turkey. (E-mail: dr_hasanarik@yahoo.com) 252 July/August 2016  Vol 106  No 4  Journal of the American Podiatric Medical Association