Intramedullary Nailing for Distal Ulna Fractures: Step-by-Step Procedure
Intramedullary nailing of distal ulna fractures is best performed using an intrafocal pin plate technique, which provides stable intramedullary fixation through a minimally invasive approach, particularly effective for subcapital fractures associated with distal radius fractures. 1
Patient Selection and Indications
Ideal candidates include:
- Subcapital distal ulna fractures that are unstable and displaced 1
- Fractures associated with concomitant distal radius fractures requiring stable ulnar buttress 1
- Young patients requiring rapid functional rehabilitation 2
- Fractures with severe displacement, angulation, or translation 2
Contraindications to avoid:
- Ulnar head fractures (require plate fixation instead) 1
- Segmental fractures with proximal extension 1
- Open fractures with gross contamination 1
- Active infection 1
- Stable, nondisplaced fractures 2
Preoperative Planning
Assess for associated injuries:
- Evaluate distal radioulnar joint (DRUJ) stability after any radius fixation 3
- Check for median nerve dysfunction if distal radius fracture present 4
- Obtain radiographs to confirm fracture pattern and rule out intra-articular extension 2
Surgical Technique: Intrafocal Pin Plate Method
Step 1: Patient Positioning and Approach
- Position patient supine with arm on hand table 1
- Make a small distal incision over the ulnar aspect of the wrist 1
- Use a straight incision between extensor carpi ulnaris and flexor carpi ulnaris 2
- Preserve the dorsal branch of the ulnar nerve during dissection 2
Step 2: Plate Insertion and Reduction
- Insert the curved intrafocal pin plate through the distal incision 1
- Advance the plate proximally into the intramedullary canal 1
- Use the natural curve of the plate to obtain multiple points of fixation within the canal 1
- Allow the distal overhang of the plate to reduce the fracture by acting as a buttress 1
Step 3: Fracture Reduction Verification
- Confirm anatomical reduction of the distal ulna fracture 2
- Verify restoration of DRUJ congruency 3
- Check that axial alignment is maintained without translation >2mm 3
Step 4: Fixation
- Secure the plate using unicortical locking screws in the ulnar head 1
- Avoid plate impingement in the articular zone 2
- Ensure stable construct that allows functional rehabilitation without cast immobilization 2
Step 5: Wound Closure
Postoperative Management
Immediate postoperative care:
- Avoid postoperative splint in isolated distal ulna fractures with stable fixation 2
- Apply elastic bandage only for 24-48 hours 2
- Initiate active finger motion exercises immediately to prevent stiffness 5, 6
Weight-bearing protocol:
- Restrict to light activities of daily living for first 4 weeks to protect osteosynthesis 2
- Progress to heavier weight-bearing after 4 weeks as tolerated 2
Adjunctive treatments:
- Apply ice at 3 and 5 days post-injury for symptomatic relief 5, 6
- Consider low-intensity ultrasound for short-term pain improvement, though long-term benefits unproven 5, 6
Follow-up imaging:
- Obtain radiographs at 3 weeks to assess healing 6
- Repeat imaging at completion of immobilization period if used 5
Expected Outcomes and Complications
Advantages of operative fixation:
- Provides stable ulnar buttress aiding distal radius reduction 1
- Restores DRUJ stability and function 3
- Achieves better functional outcomes (ROM 95.7%, MWS 91.2 points, QDASH 3.5 points) compared to conservative treatment 3
- All patients typically progress to union 1
Common pitfalls to avoid:
- Conservative treatment of base fractures leads to 60% non-union rate and 75% DRUJ instability 3
- Malunion with >2mm displacement causes limited forearm rotation 3
- Hardware prominence requiring removal is rare with intrafocal technique 1
Special Considerations for Associated Ulnar Styloid Fractures
Tip fractures (distal two-thirds) do not require fixation: