Distal Tibia Fracture - Intramedullary Nailing

Treatment Algorithm

Rockwood & Green's Fractures in Adults, 10th ed - Authors' preferred treatment algorithm for tibia fractures

Indications and Decision-Making

• Direct bending - transverse/oblique fractures, same-level fibular fractures, no intraarticular extension, more severe soft-tissue injury
• Torsional forces - spiral fractures, different-level fibular fracture, frequent intraarticular involvement of medial or posterior malleolus

Preoperative Planning

• Measure nail length using the tibial tubercle-medial malleolar distance (most accurate method)
• Nail diameter: measure the tibia at its narrowest point on lateral radiograph
• Use contralateral tibia radiographs for severely comminuted fractures
• The nail should be countersunk proximally with the distal end centered to slightly lateral in the distal epiphysis
• Account for potential impaction if dynamization is planned - choose length accordingly to prevent nail migration into ankle joint
• Reamed vs unreamed: Reamed nailing is preferred for fractures with minor soft-tissue injury; unreamed (8-10 mm nails) reserved for more extensive soft-tissue injury. Reaming allows larger, stronger implants. - Campbell's, p. 3356

Nail Design Considerations for Distal Fractures

• Two distal locking screws are required to prevent recurvatum deformity from rotation around a single distal screw
• Nails with more distally placed distal locking screws improve the ability to treat very distal tibial fractures
• Modern implant designs with tighter distal screw clusters have facilitated treatment without need for implant modification
• Some nails offer additional anteroposterior distal screw holes for improved distal purchase - Campbell's, p. 3356

Positioning

1. Calcaneal traction pin placed before positioning
2. Patient supine, hip flexed 45°, knee flexed 90°
3. Well-padded crossbar proximal to popliteal fossa
4. Apply traction, confirm reduction under fluoroscopy, then release traction temporarily
5. Reapply traction after entry portal is made

1. Patient supine, thigh over padded bolster
2. Skilled assistant to help with fracture reduction and limb support
3. A femoral distractor or two-pin external fixator can maintain reduction - Schanz pin 1 cm distal to knee (placed posteriorly to avoid nail path), second pin 1 cm proximal to ankle

• Campbell's TECHNIQUE 59.9, p. 3356-3357

The Core Challenge: Distal Fracture Malalignment

Reduction Techniques

Blocking (Poller) Screws

• Screw is placed on the concave side of the deformity (i.e., where you want to prevent the nail from going)
• For distal varus: place blocking screw in the lateral aspect of the distal fragment
• For distal valgus: place blocking screw medially
• Can be placed on the convex side if positioned at a distance from the fracture
• Screws can be left in place permanently to increase construct stability - particularly valuable in geriatric patients with wider tibiae and poor bone quality
• If malalignment has already occurred: remove the nail, insert blocking screws, ream a new pathway - Rockwood & Green's, p. 3221-3222

Other Reduction Adjuncts

• Percutaneous reduction clamps
• Provisional unicortical unlocked plating (unicortical screws ≤10 mm) - plate removed prior to wound closure in open fractures
• Suprapatellar (semi-extended) approach - reduces deforming pull of extensor mechanism
• Femoral distractor or temporary external fixator ("traveling traction")
• Intramedullary fracture reducer/"finger" device available in most nail sets

Fibula Fixation - Controversial but Often Useful

• Simple fibular fracture patterns
• Very distal tibial fracture patterns

• Malreduction of the fibula will prevent accurate tibial reduction - fix fibula first and verify alignment
• Fibular plating keeps the tibia out to length laterally but does not prevent varus collapse
• One study reported an 8-fold increased nonunion risk with combined fibula plating + tibia nailing; later studies have not confirmed this magnitude of risk
• Current position: Whether to fix the fibula in distal tibia fractures remains controversial - Rockwood & Green's, p. 3222

Locking and Dynamization

• All unstable fractures: minimum 2 screws distally and 2 proximally to maintain length and prevent rotation
• Static locking is routine
• Distal fixation: freehand "perfect circle" technique under fluoroscopy
• Consider dynamization for delayed union - but ensure adequate fracture healing is present before weight-bearing, especially in comminuted distal patterns, to prevent coronal plane malalignment
• Overall union rates of 96% have been reported after reamed nailing of distal tibial fractures - Campbell's, p. 3355

Associated Articular Injuries

• Medial malleolus fractures: Cancellous lag screws to stabilize before or after nailing
• Posterior malleolus fractures: Cancellous lag screws; open reduction if intraarticular displacement is present
• Ankle joint involvement: Open reduction required for intraarticular displacement
• Distal fibula fractures: Plate if necessary for ankle joint stability or severe displacement; distal fibular fixation is useful in very distal fractures to facilitate tibial alignment

IMN vs Plate Fixation - Evidence Summary

Key Pearls

1. CT before nailing - rule out articular extension (43A vs 43B/C)
2. Two distal locking screws minimum - prevents recurvatum from rotational failure around one screw
3. Blocking screws are your most powerful tool for controlling distal fragment alignment
4. Plate the fibula first in same-level fractures if fibular fixation is planned - then check tibial alignment
5. Suprapatellar approach reduces deforming forces and makes intraoperative fluoroscopy easier distally
6. Malalignment is the Achilles heel of distal tibia nailing - weight-bearing restrictions must be followed until significant fracture healing occurs
7. 96% union rate is achievable with reamed nailing using modern technique