What is the appropriate management for a non-displaced angulated fracture of the 4th metacarpal shaft in an otherwise healthy individual?

Management of Non-Displaced Angulated 4th Metacarpal Shaft Fracture

For a non-displaced angulated fracture of the 4th metacarpal shaft, immobilize the hand with an ulnar gutter splint in the position found without attempting to straighten the fracture, and refer to orthopedics for definitive management based on the degree of angulation. 1, 2

Initial Assessment and Imaging

• Obtain 3-view radiographs of the hand (posteroanterior, lateral, and 45° semipronated oblique) to confirm the diagnosis and precisely measure the degree of angulation. 3
• Assess for rotational deformity by examining finger cascade when the patient makes a fist—all fingers should point toward the scaphoid tubercle without overlap or scissoring. 4
• Check for vascular compromise immediately—if the hand appears blue, purple, or extremely pale, activate emergency medical services as this indicates compromised perfusion requiring urgent intervention. 1, 2

Immobilization Technique

• Do not attempt to straighten or manipulate the angulated fracture in the initial setting, as first aid providers and primary care clinicians should splint in the position found. 1, 2
• Apply a padded ulnar gutter splint to immobilize the 4th and 5th metacarpals with the wrist in slight extension and the metacarpophalangeal joint flexed to 60-90 degrees. 2, 5
• This splinting approach reduces pain, prevents additional soft tissue injury, and facilitates safe transport to definitive care. 2

Treatment Decision Algorithm Based on Angulation

Conservative (Non-Operative) Management:

• Acceptable for angulation ≤30 degrees, no malrotation, no shortening >5mm, and no joint involvement. 5
• Continue ulnar gutter splinting for 4-5 weeks with radiographic follow-up to confirm healing. 6
• Early functional treatment can begin once soft tissue swelling resolves, using buddy taping to the 5th digit. 5
• Most metacarpal fractures, including stable 4th metacarpal shaft fractures, can be successfully treated non-operatively with this approach. 4, 7

Surgical Management Indications:

• Angulation >30 degrees requires surgical intervention, typically with intramedullary stabilization. 5
• Presence of malrotation, regardless of angulation degree, necessitates operative fixation. 4, 5
• Axial shortening >5mm indicates instability requiring surgical treatment. 5
• Multiple metacarpal fractures (serial fractures) should be treated surgically. 5

Surgical Options When Indicated

• Intramedullary Kirschner wire fixation or intramedullary compression screws are both valid options for shaft fractures, with similar outcomes regarding range of motion, bone healing, and return to work. 8
• Intramedullary screws may allow slightly earlier return to work and show a tendency toward achieving full total active motion. 8
• Plate and screw fixation provides the most rigid construct for early mobilization when fracture pattern is appropriate. 4, 7

Critical Pitfalls to Avoid

• Never apply ice directly to the injury site as this can cause tissue ischemia—use cold packs with a barrier if cooling is needed for pain control. 1
• Avoid attempting closed reduction of angulated 4th metacarpal fractures in the outpatient setting, as this is generally unsuccessful and may cause additional soft tissue damage. 5
• Do not miss rotational deformity on initial examination, as this is an absolute indication for surgical correction regardless of other fracture characteristics. 4, 5
• Ensure the splint does not cause excessive pressure or compromise circulation—check neurovascular status before and after splint application. 2

Follow-Up and Return to Activity

• Radiographic evidence of circumferential callus formation at the fracture site indicates readiness for return to full activity, typically at 4-5 weeks. 6
• Early mobilization after surgical fixation is critical to prevent stiffness and restore function, with the specific timing based on the stability of the fixation construct. 7
• Athletes with stable, non-displaced fractures treated conservatively can return to modified activity within 2 weeks and full participation by 4 weeks using protective splinting. 6