What is the treatment for a Salter-Harris II fracture of the distal radius?

Treatment of Salter-Harris II Fracture of the Distal Radius

Salter-Harris II fractures of the distal radius should be treated with closed reduction under general anesthesia followed by cast immobilization for 3-6 weeks, with radiographic verification between days 7-14 to prevent malunion. 1

Initial Management Algorithm

Immediate Assessment and Reduction

• Perform closed reduction emergently, preferably in the operating room under general anesthesia rather than in the emergency department, as this provides optimal conditions for accurate reduction 1
• Assess the degree of displacement to guide treatment intensity:
  • Displacement <3mm: Cast immobilization alone 2
  • Displacement ≥3mm: Closed reduction followed by cast immobilization 1, 2

Immobilization Protocol

• Apply cast immobilization for 30-45 days depending on patient age 1
• Shorter immobilization periods (1-3 weeks) may be considered for surgically fixed fractures in adults, but pediatric Salter-Harris fractures require longer immobilization to protect the growth plate 3, 1
• Critical verification point: Obtain radiographs between day 7-14 post-reduction to detect early malunion, as this is when displacement commonly occurs 1

Active Rehabilitation

• Initiate active finger motion exercises immediately following diagnosis to prevent stiffness, which is one of the most functionally disabling complications 4
• Finger motion does not adversely affect adequately stabilized fractures 4
• Begin wrist mobilization after cast removal with a standardized exercise program for 6 weeks 3

Surgical Intervention Indications

When Closed Reduction Fails

• If closed reduction cannot achieve <3mm displacement, proceed to open reduction with internal fixation 2
• Use surgical techniques that avoid violating the growth cartilage, such as transepiphyseal wire fixation that respects the physis 1
• Remove any interposed soft tissue during open reduction 5

Management of Malunions

• Neglected or incorrectly treated fractures leading to malunion require surgical correction 1
• Open reduction with internal fixation using techniques that avoid growth plate damage can restore radiocarpal joint alignment 1
• Recovery of normal joint mobility after malunion correction takes 3-6 months depending on patient age 1

Common Pitfalls and Caveats

Critical Monitoring Period

• The 7-14 day window is crucial: Loss of reduction commonly occurs during this period, making radiographic verification mandatory 1
• Failure to verify reduction leads to malunion requiring surgical intervention 1

Growth Plate Considerations

• Premature physeal closure can occur even with optimal treatment, though the evidence for this complication primarily comes from distal tibia studies 5
• Surgical fixation should use techniques that minimize growth plate trauma 1

Rare Complications

• Extensor tendon rupture can occur with volarly displaced Salter-Harris II fractures, though this is uncommon 6
• Monitor for signs of tendon injury during follow-up 6

Adjunctive Treatments

• Ice application provides benefit at 3 and 5 days post-injury 7
• Low-intensity ultrasound may improve pain and radiographic union in the short term, though long-term benefits are unproven 7

Follow-up Protocol

• Radiographic follow-up at approximately 3 weeks and at immobilization removal 4
• Continue monitoring until skeletal maturity to detect late growth disturbances 1
• Return to normal activities typically occurs after 30-45 days of immobilization in properly treated cases 1