A 22-year-old male presents with hand pain after punching a wall. What is the treatment of choice for his fifth metacarpal fracture?

In cases of a fifth metacarpal fracture, commonly referred to as a "boxer's fracture," the most appropriate treatment is the application of an ulnar gutter splint to immobilize the fracture site. This type of splint effectively stabilizes the fifth and fourth digits of the hand, providing the necessary support while allowing for some degree of mobility in the uninjured fingers.

Immobilization is crucial in managing these fractures because it helps to prevent further injury, reduces pain, and facilitates healing. The ulnar gutter splint is designed to keep the affected metacarpal in a position that promotes alignment and healing, typically at a 70-degree flexion at the MCP joint, which is optimal for recovery.

While surgical fixation and immediate orthopedic consult may be necessary for more severe fractures or cases involving significant displacement, for many fifth metacarpal fractures, conservative treatment with an ulnar gutter splint is effective and often the first-line approach. Casting and long finger splinting are less favored in this specific context as they do not afford the same level of protection and immobilization for the involved digit, which is why they are not the preferred choice in the management of this particular fracture.