What is the treatment for a fracture of the fourth metacarpal shaft?

Treatment of Fourth Metacarpal Shaft Fractures

The treatment of fourth metacarpal shaft fractures should primarily be non-operative with a functional hand-based splint that allows for early range of motion, unless there is significant displacement, angulation, rotation, or shortening that would require surgical intervention. 1

Initial Assessment and Imaging

• Standard radiographic examination should include at least 3 views (posteroanterior, lateral, and 45° semipronated oblique) to properly visualize metacarpal fractures 2
• An internally rotated oblique projection, in addition to the standard externally rotated oblique, increases diagnostic yield for metacarpal fractures 2
• CT imaging is usually not indicated unless there is concern for complex articular involvement 2

Treatment Algorithm

Non-operative Management (First-line for most cases)

• Indicated for stable, non-displaced or minimally displaced fractures 3
• A hand-based functional splint that allows metacarpophalangeal joint, interphalangeal joint, and radiocarpal joint motion is recommended 1
• The average splint duration is approximately 24 days 1
• Benefits of functional splinting include:
  • Excellent maintenance of fracture reduction 1
  • Early or immediate return to pre-injury activities 1
  • Low patient morbidity 1
  • Maintained functional motion throughout treatment 1

Surgical Management

• Indicated when fractures are unstable, significantly angulated, malrotated, or shortened 4
• Surgical options include:
  • Percutaneous Kirschner wire fixation 4
  • Intramedullary fixation 4
  • Plate and screw fixation 3
  • Interfragmentary screws 3
• For simple, spiral, distal or shaft fractures, both intramedullary Kirschner wiring and intramedullary compression screws are valid options with similar outcomes in terms of:
  • Total active range of motion 4
  • Rotation 4
  • Bone healing 4
  • Return to work time 4

Post-Treatment Management

• Active finger motion exercises should be initiated immediately following diagnosis and treatment to prevent stiffness 2
• Wrist motion does not need to be started early following stable fracture fixation 2
• When external fixation is used, limiting the duration of fixation is recommended to reduce complications 2
• Consider vitamin C supplementation for prevention of disproportionate pain 2

Potential Complications to Monitor

• Finger stiffness is the most common functionally disabling complication 2
• Other complications include malunion, nonunion, and hardware-related issues 5

Special Considerations

• Treatment should be tailored to the fracture pattern and patient factors 3
• Most patients with hand-based functional splints can continue working without missing days (20 out of 24 patients in one study) 1
• Primary goals of treatment are to achieve anatomic and stable reduction, bony union, and early mobilization to minimize disability 6