Treatment of Nondisplaced Radial Head Fractures (Mason Type I)
Nondisplaced radial head fractures (Mason Type I) should be treated nonoperatively with 48 hours of rest in a sling followed by immediate active mobilization, avoiding cast immobilization entirely. 1
Initial Management
Early mobilization is the cornerstone of treatment. The optimal protocol consists of:
- Brief immobilization for comfort only: Use a broad arm sling for 2 days maximum 1, 2
- Joint aspiration for pain relief: Hematoma aspiration is safe and effective for reducing pain and may facilitate earlier motion 1
- Avoid cast immobilization: Prolonged immobilization leads to stiffness and should never be used 1
Active Range of Motion Protocol
Begin active mobilization after the initial 48-hour rest period:
- Encourage stretching beyond the painful range once collateral ligament stability is confirmed 2
- Physical therapy support if needed: While mobilization should be encouraged, formal physical therapy can be provided if patients struggle with self-directed exercises 1
- No mechanical restrictions: These fractures by definition have no mechanical block to pronation/supination 3
Follow-Up Strategy
Minimal follow-up is appropriate for uncomplicated Mason Type I fractures:
- Single outpatient visit at 2 days: Assess collateral ligament stability (varus-valgus stress testing) and ensure no mechanical block to motion 2
- Discharge with return precautions: Patients can be discharged after the first visit with instructions to return only if no clinical improvement occurs by 6 weeks 2
- Avoid routine radiographic follow-up: Frequent x-rays do not modify treatment and expose patients to unnecessary radiation and costs 4
Common Pitfall: Overtreatment
Surgeons frequently "over-treat" Mason Type I fractures with excessive follow-up visits and radiographs (averaging 4.4 additional x-rays per patient) without any change in management 4. This practice increases healthcare costs and radiation exposure without improving outcomes 4.
Clinical Outcomes
Excellent functional results are expected in the majority of patients:
- Good to excellent outcomes in 80% of cases with appropriate early mobilization 1
- Up to 20% may experience residual symptoms: Some patients report loss of extension or residual pain, though these are typically minor 1
- Rare complications exist: While uncommon, potential late complications include painful osteoarthritis with stiffness, posterolateral rotatory instability, or symptomatic loose bodies 5
Key Assessment: Rule Out Associated Injuries
The radial head is a secondary stabilizer, and associated injuries must be excluded:
- Assess for mechanical block: Any limitation of pronation/supination suggests a more significant injury pattern 3
- Evaluate ligament stability: Test collateral ligaments at the first follow-up visit 2
- Consider the elbow extension test: This clinical test has high sensitivity (88-97.6%) for detecting occult fractures if diagnosis is uncertain 1
If there is any evidence of instability, mechanical block, or associated injuries, the fracture should be reclassified and managed accordingly 3.