Malunion, Delayed Union and Nonunion

• Articular (intra-articular malunion)
• Metaphyseal
• Diaphyseal

• Uniplanar (varus/valgus OR sagittal only)
• Biplanar (oblique - combined coronal and sagittal)
• Multiplanar (includes rotational component)

• Simple: Single CORA, no translation
• Complex: Multiple CORAs, translation, rotational, or associated infection

• Minimum of 9 months since injury
• No visible progressive signs of healing for 3 consecutive months
• Will not heal without intervention

• Fracture has not healed within expected timeframe (typically 3-6 months)
• BUT shows continued signs of healing potential

Aseptic hypertrophic femoral or tibial shaft nonunions

• Reaming deposits morselised autograft (biological effect)
• Larger nail increases bending and torsional stiffness (mechanical effect)

Over 90% for femur, approximately 85% for tibia

1. Remove existing nail
2. Identify nonunion site
3. Over-ream canal to 1-2mm larger than previous reamer
4. Insert nail 1-2mm larger diameter than previous
5. Static or dynamic locking based on stability
6. Consider Poller (blocking) screws in wide canals

Atrophic nonunions, metaphyseal locations, or forearm/humerus where nailing less ideal

1. Wide exposure of nonunion site
2. Use osteotome to lift shingles of cortical bone (decortication)
3. This creates a bleeding vascular bed
4. Apply compression plate (LCP/DCP)
5. Pack iliac crest autograft around nonunion site

• Iliac crest autograft (gold standard - has all 3 properties)
• RIA (Reamer-Irrigator-Aspirator) - lower morbidity than ICBG
• Allograft (scaffold only)
• BMP-2 (osteoinduction only - expensive)

Large bone defects (over 3-4cm) or infected nonunions requiring resection

1. Radical debridement of all dead bone and infected tissue
2. Insert PMMA cement spacer (with antibiotic if infected)
3. Stabilise with external fixator or plate to maintain length
4. Allow induced membrane to form over 6-8 weeks

1. Open membrane carefully (preserve it)
2. Remove cement spacer
3. Pack defect with cancellous autograft (RIA or iliac crest) inside the biological chamber
4. Close membrane over graft
5. Convert to internal fixation if external fixator was used

Infected nonunions, complex deformity, large defects (bone transport)

Gradual traction on living tissues creates stress that stimulates regeneration and active growth.

• Compression: Applied at nonunion site to promote healing
• Distraction osteogenesis: Applied at separate corticotomy site to restore length
• Bone transport: Moving a segment of bone to fill a defect

• Can treat infection, nonunion, and deformity simultaneously
• Generates new bone without graft

• Prolonged treatment (1 month per cm of regenerate)
• Pin site infections
• Patient compliance required

• Supine on traction table (femur) or supine on radiolucent table (tibia)
• Image intensifier positioned for AP and lateral views
• Ensure same brand nailing system available (to remove old nail)

1. Incision: Use previous incision over nail entry point
2. Expose nail: Identify end cap or locking screws
3. Remove hardware: Remove end cap and locking screws
4. Extract nail: Use appropriate extraction device
5. Assess canal: Pass flexible reamer to assess nonunion site
6. Over-ream: Ream to 1-2mm larger than previous reamer size
7. Collect reaming debris: This is autograft
8. Insert larger nail: 1-2mm greater diameter than previous
9. Lock nail: Static initially; may dynamise later
10. Poller screws: Consider if canal is wide or unstable

• Do not strip soft tissue at nonunion site
• Larger nail is critical for increased stiffness
• Blocking screws improve alignment in metaphyseal extensions

• Supine with arm table (upper limb) or supine/lateral (lower limb)
• Tourniquet if upper limb

1. Approach: Use appropriate surgical approach for bone and location
2. Expose nonunion: Full exposure of nonunion site
3. Debride: Remove fibrous tissue from between bone ends
4. Decorticate: Judet shingling technique - lift cortical shingles with osteotome
5. Reduce: Obtain anatomical reduction of bone ends
6. Apply plate: Use compression plate (LCP or DCP)
7. Compress: Use eccentric drilling or articulated tension device for axial compression
8. Harvest graft: Iliac crest or RIA for autograft
9. Apply graft: Pack graft around nonunion site
10. Close: Layered closure over drain

• Long plate with at least 8 cortices purchase each side
• Compression screws nearest nonunion site
• Onlay graft circumferentially

1. Identify mechanical axis on long-leg radiographs
2. Draw proximal and distal joint orientation lines
3. Draw proximal and distal mechanical axis lines
4. Intersection point = CORA

• Osteotomy at CORA: Simple angular correction, realignment is perfect
• Osteotomy away from CORA: Needs translation plus angulation

• Previous approach
• Autograft harvest equipment (RIA or iliac crest)
• Internal fixation if converting from external fixator

1. Incision: Open previous wound
2. Identify membrane: Preserve the induced membrane capsule
3. Open membrane: Make longitudinal incision in membrane
4. Remove spacer: Extract cement spacer carefully
5. Prepare bed: Light curettage of bone ends
6. Harvest graft: RIA from femur or iliac crest
7. Pack graft: Fill defect completely with morselised cancellous graft
8. Close membrane: Repair membrane over graft
9. Stabilise: Convert to internal fixation or maintain stable frame
10. Close: Layered closure

• Do NOT discard the membrane - it is highly vascular and secretes growth factors
• Pack graft tightly to fill all dead space
• Stable fixation is essential for graft incorporation