Initial Management of Oblique Mid to Distal Ulnar Shaft Fracture
For an oblique mid to distal ulnar shaft fracture, apply a sugar-tong splint initially for 5-7 days, then transition to a functional forearm brace with early mobilization if the fracture is stable (displacement <50%, angulation <10°). 1, 2, 3
Immediate Assessment and Stability Determination
Assess fracture stability using these criteria:
- Unstable fractures: displacement >50% of shaft width, angulation >10°, or proximal third location 2
- Stable fractures: displacement <50%, angulation <10°, with intact interosseous membrane 3
- Mid to distal ulnar shaft fractures are typically more stable than proximal fractures 2
Initial Immobilization Protocol
Apply a sugar-tong splint as the initial immobilization method 4:
- Sugar-tong splinting effectively maintains reduction in forearm fractures, with 90% of loss of reduction occurring in the first 2 weeks 4
- Mid-shaft fractures demonstrate superior stability with sugar-tong splinting compared to distal fractures (17% vs 44% loss of reduction) 4
- Maintain splint for approximately 5-7 days until pain is mild 3
Transition to Functional Bracing (For Stable Fractures)
After 5-7 days, transition to a prefabricated functional forearm brace 3:
- Functional bracing of stable ulnar shaft fractures achieves union in 7.3 weeks on average (range 6-9 weeks) 3
- This approach results in full range of motion recovery in 97% of patients 3
- Early mobilization without prolonged immobilization reduces healing time from 10.5 weeks to 6.7 weeks and eliminates nonunion risk 5
Initiate active finger motion exercises immediately to prevent stiffness, which is one of the most functionally disabling complications 1:
- Continue brace until radiographic union is confirmed 3
- Advance upper extremity to full functional use as tolerated 3
Surgical Indications
Refer for surgical fixation (open reduction and internal fixation with compression plating) if the fracture is unstable 2:
Follow-Up Protocol
Obtain radiographic follow-up at approximately 3 weeks and at time of immobilization removal 1:
- Monitor for loss of reduction, particularly in the first 2 weeks 4
- Average forearm rotation loss is only 5° with functional bracing approach 5
Critical Pitfalls to Avoid
Avoid prolonged immobilization beyond what is necessary for pain control 1:
- Extended casting increases healing time and complication rates without improving outcomes 5
- Immobilization-related complications occur in 14.7% of cases, including skin irritation and muscle atrophy 1
- The traditional approach of axilla-to-palm casting for 10+ weeks results in 8% nonunion rate versus 0% with early mobilization 5