Non-thumb metacarpal fracture (neck)
Background
Clinical Features
- TTP or ecchymosis on the palmar bony surface is highly suggestive of fracture
- Loss of the normal knuckle contour
- Due to dorsal angulation of fracture apex due to pull of the interosseous muscles
Differential Diagnosis
Hand and Finger Fracture Types
Examination
- Hand xrays
Hand Examination
- Assess angulation[1]
- Head-to-neck angle of the metacarpals is normally 15 degrees
- Fracture angulation = measured angle minus 15 deg
- Angle toleration (below which there is no adverse functional outcome)
- 2nd MC < 10 deg
- 3rd MC < 20 deg
- 4th MC < 30 deg
- 5th MC < 30-40 deg
- Head-to-neck angle of the metacarpals is normally 15 degrees
- Assess rotational alignment by looking for overlap of the 5th over the 4th digit (scissoring or psuedoscissoring)
- Assess extensor apparatus
- Assess skin integrity
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:
- Pseudo-clawing
- Significant angulation (>10-15 degrees of the 2nd through 4th fingers, 20-30 degrees of the 5th) [2]
- Any rotational misalignment
- Reduction technique:
- Pain control and/or Hematoma block
- Flex MCP joint to 90 degrees then apply axial traction while placing pressure over metacarpal shaft
- Radial gutter splint if 2nd/3rd MCP fractures, Ulnar gutter splint if 4th/5th. Immobilize with wrist extended 20-30 degrees and MCP flexed 90 degrees
- Can be difficult to reduce or maintain reduction. Early hand referral if not successful
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
- MCP joints in 70-90 deg flexion, wrist in 20-30 deg extension, PIP and DIP joints in 5-10 deg of flexion[3]
Disposition
- Outpatient
Refer for
- Comminution
- Rotational malalignment
- Unsuccessful reduction if required[1]
See Also
References
- ↑ 1.0 1.1 German C. Hand and wrist emergencies. In: Bond M, ed. Orthopedic Emergencies: Expert Management for the Emergency Physician. Cambridge: Cambridge University Press; October 31, 2013.
- ↑ Davenport M. Procedures for orthopedic emergencies. In: Bond M, ed. Orthopedic Emergencies: Expert Management for the Emergency Physician. Cambridge: Cambridge University Press; October 31, 2013.
- ↑ Hofmeister, EP. Comparison of 2 methods of immobilization of fifth metacarpal neck fractures: a prospective randomized study. The Journal of Hand Surgery. 2008; 33(8):1362-1368.