Non-thumb metacarpal fracture (shaft)

Background

• Extensor tendons and the FDS attach to the middle phalanx
• Commonly will have volar angulation due to interosseous muscles and extensor tendon attachments

Clinical Features

• TTP along affected metacarpal
• Flexion at MCP is difficult

Differential Diagnosis

Hand and Finger Fracture Types

• Non-thumb metacarpal fractures
  • Head
  • Neck
  • Shaft
  • Base
  • Boxer's fracture
• Thumb fracture
• Finger (Phalanx) Fracture
  • Proximal
  • Middle
  • Distal

Evaluation

Imaging

• Hand x-rays
  • Oblique fracture are more prone to shorten and rotate
  • Transverse fracture generally stable (particularly isolated 3rd or 4th MC shaft fracture)

Physical

• Assess for extensor dysfunction; patient may exhibit "pseudo-clawing" during attempts at finger extension
• Assess angulation
  • >10 deg in 2nd and 3rd and >20 deg in 4th and 5th metacarpal shaft fractures requires reduction
• Assess rotational alignment

Management

General Fracture Management

• Acute pain management
• Open fractures require immediate IV antibiotics and urgent surgical washout
• Neurovascular compromise from fracture requires emergent reduction and/or orthopedic intervention
• Consider risk for compartment syndrome

Acute Reduction

• Acute reduction indicated if there is pseudo-clawing or significant angulation
  • Closed reduction generally corrects angulation but typically does not restore length

Metacarpal Fracture (Post-Reduction) Goals

Finger	Shaft Angulation (degrees)	Shaft Shortening (mm)	Neck Angulation (degrees)	Rotational Deformity
Index & Long Finger	10-20	2-5	10-15	None
Ring Finger	30	2-5	30-40	None
Little Finger	40	2-5	50-60	None

Immobilization

• Ulnar Gutter Splint or Radial Gutter Splint

Disposition

• Refer:
  • Malrotation
  • Comminution
  • Shortening > 5mm (refer all shortening if not familiar with fracture management)
  • 2 or more metacarpal fractures
  • Unacceptable angulation
  • Long oblique fractures

See Also

• Hand and finger fractures