Ulnar Gutter Splint for Boxer's Fracture
For a boxer's fracture of the 5th metacarpal neck, use an ulnar gutter splint or hand-based functional splint that immobilizes the 4th and 5th metacarpals while allowing metacarpophalangeal (MCP) joint motion of the uninjured fingers. 1
Splinting Technique and Positioning
Apply an ulnar gutter splint that extends from the proximal forearm to just beyond the fingertips of the 4th and 5th digits, maintaining the hand in the "safe position" with the MCP joints in 70-90 degrees of flexion and the interphalangeal (IP) joints in slight flexion 1
Alternatively, use a hand-based functional splint that stabilizes the fracture while allowing MCP, IP, and radiocarpal joint motion throughout treatment, which has been shown to maintain excellent fracture reduction with minimal patient morbidity 2
Ensure the splint is padded and comfortably tight but not constrictive to avoid compromising circulation 1, 3
Splint the fracture in the position found unless straightening is necessary to facilitate safe transport to a medical facility—do not attempt to reduce angulated fractures in the first aid setting as this may cause further injury 1, 4
Indications for Splinting vs. Surgical Intervention
Non-operative splinting is appropriate for fractures with volar angulation up to 70 degrees without malrotation, as immediate mobilization with pressure bandage alone has shown equivalent outcomes to cast immobilization 5
Surgical fixation is indicated when there is excessive volar angulation (>70 degrees), significant shortening, or rotational deformity of the 5th finger 6, 7
Check for vascular compromise immediately: if the extremity is blue, purple, or pale, activate emergency medical services immediately as this represents a limb-threatening emergency 1, 8
Duration of Immobilization and Early Motion
Continue rigid splinting for 3-4 weeks with radiographic follow-up at approximately 3 weeks to assess healing 3, 4
Begin active finger motion exercises immediately for all uninjured fingers, as finger motion does not adversely affect adequately stabilized fractures and prevents the functionally disabling complication of finger stiffness 1, 3
Finger stiffness is one of the most functionally disabling adverse effects following hand fractures and can be very difficult to treat after healing, potentially requiring multiple therapy visits and surgical intervention 1, 4
The average splint duration is approximately 24 days when using a hand-based functional splint, with most patients able to return to work immediately or within days 2
Common Pitfalls to Avoid
Over-immobilization leads to unnecessary stiffness: avoid rigid splinting when functional splinting or buddy taping would suffice, as prolonged immobilization beyond what is necessary causes joint stiffness that is difficult to reverse 3, 4
Do not immobilize uninjured fingers: instruct patients to move all uninjured fingers regularly through complete range of motion from the first encounter to minimize risk of complications 1, 3
Cover any open wounds with a clean dressing before splinting to lower the risk of contamination and infection 1
Ensure adequate initial radiographs: obtain three views (PA, lateral, and oblique) to detect displacement, angulation, and articular involvement 3