Metacarpal stress fractures, although rare in the general population, are not uncommon in high performance athletes and may be seen in individuals with chronic pain associated with sports activity and with no history of acute trauma. Stress fracture fixation in skeletal long bones with different methods and implants have been discussed in the literature, both for patients who had conservative treatment failure and prophylactically. We describe the use of intramedullary cannulated screw fixation for the treatment of a 26-year-old professional boxer who complained of hand pain and swelling with 18 months evolution. After 30 days of post-operative evolution, the patient had no pain on palpation of the metacarpal base and, after three months, he was back to boxing. This is a level V evidence study. Written informed consent was obtained from the patient for publication of this case report and accompanying images.