Dupuytren Fracture-Dislocation of the Ankle

Historical Note

Definition

• A fracture of the lower end (distal shaft) of the fibula at or above the level of the tibiofibular syndesmosis (suprasyndesmotic)
• Associated complete disruption of the syndesmotic ligament complex
• Medial-sided injury (deltoid ligament rupture or medial malleolus fracture)
• Lateral or posterolateral dislocation of the talus from the ankle mortise
• It is essentially a high-energy variant of the Pronation-External Rotation (PER) pattern in the Lauge-Hansen classification

Anatomy Relevant to This Injury

Mechanism of Injury

Step-by-Step Sequence (Lauge-Hansen PER Stages)

Staged bone model showing Pronation-External Rotation injury progression (Stages 1-4)

In Dupuytren's original description, the fibular fracture sits just above the syndesmosis (lower fibular shaft), whereas in Maisonneuve the fracture extends to the fibular neck. Both represent PER injuries of differing energy.

Common Mechanisms in Clinical Practice

• Twisting falls with foot planted in eversion - sports injuries (football, rugby, skiing)
• Road traffic accidents - passenger or pedestrian with externally rotated, pronated foot
• Falls from height with foot landing in eversion
• Industrial injuries - machinery catching the foot

Associated Injuries

Bony Injuries

• Posterior malleolus fracture (trimalleolar equivalent) - present in ~30-50% of cases
• Medial malleolus fracture (or isolated deltoid ligament rupture)
• Proximal fibula fracture (full Maisonneuve pattern)
• Osteochondral injury to the talar dome (articular cartilage shearing during dislocation)
• Calcaneal fractures in high-energy falls

Ligamentous Injuries

• Complete syndesmotic disruption (AITFL + interosseous ligament + PITFL)
• Deltoid ligament rupture (deep and superficial)
• Lateral ligament complex injury (if foot supinated secondarily)

Soft Tissue & Neurovascular Injuries

• Peroneal tendon injury or dislocation
• Skin compromise - skin tenting over the lateral malleolus is a surgical emergency requiring urgent reduction
• Posterior tibial artery / peroneal artery injury with vascular compromise
• Superficial peroneal nerve injury (dorsal foot numbness)
• Sural nerve injury
• Compartment syndrome of the leg (rare but must be excluded in high-energy cases)

Classification Systems

1. Lauge-Hansen Classification (Mechanism-Based)

• PER Stage III - Medial injury + syndesmotic disruption + suprasyndesmotic fibular fracture
• PER Stage IV - Above + posterior malleolus fracture/PITFL rupture

2. Danis-Weber / AO-OTA Classification (Radiographic)

3. Number of Malleoli Involved (Descriptive)

• Bimalleolar fracture - fibula fracture + medial malleolus fracture
• Bimalleolar equivalent - fibula fracture + deltoid ligament rupture (medial malleolus intact but medial side disrupted)
• Trimalleolar fracture - bimalleolar + posterior malleolus fracture

Signs and Symptoms

History

• High-energy twisting or rotational injury
• Foot typically in eversion/pronation at time of impact
• Immediate inability to bear weight
• Immediate severe pain and swelling

Symptoms

• Severe pain around the ankle and lower leg
• Inability to weight-bear
• Sensation of something "giving way" or a "crack/snap" heard at time of injury
• Paresthesia or numbness in the foot (nerve injury)
• Coolness or pallor of foot (vascular compromise, if present)

Signs on Examination

• Gross swelling of the entire ankle and lower leg
• Obvious deformity - lateral or posterolateral displacement of the foot relative to the leg
• Skin tenting or puckering over the medial malleolus or laterally (indicates impending skin necrosis - URGENT)
• Bruising extending up the leg
• Open wound in open fracture-dislocations
• Foot held in eversion and external rotation

• Point tenderness along the fibula above the ankle (suprasyndesmotic region)
• Tenderness over the medial malleolus or deltoid ligament
• Tenderness over the entire syndesmotic region
• Crepitus on palpation
• Capillary refill, peripheral pulses (dorsalis pedis, posterior tibial) - assess vascular status
• Sensation testing of foot dorsum (superficial peroneal nerve) and sole

• Range of motion severely restricted or impossible due to pain/deformity
• Do NOT attempt active or passive movement if dislocation is suspected until imaging

• External rotation stress test - external rotation of the foot with knee at 90° - pain/widening indicates syndesmotic disruption
• Cotton test - lateral stress on the talus
• Squeeze test (Hopkin's test) - compressing fibula against tibia at mid-calf - pain at the ankle indicates syndesmotic injury

Investigations

Plain Radiographs (First Line)

Suprasyndesmotic oblique fibular fracture with lateral talar translation consistent with Pronation-External Rotation (PER) - Dupuytren pattern (from Miller's Review of Orthopaedics)

AP radiograph of PER ankle fracture showing suprasyndesmotic fibular fracture (Weber C pattern)

• If no obvious dislocation but syndesmotic disruption suspected - gravity stress view or externally applied stress view
• Widening of medial clear space confirms instability

CT Scan (Second Line)

• Preoperative planning for all operative cases
• Assessment of posterior malleolus fracture size and displacement
• Assessment of articular comminution
• Identification of associated injuries (osteochondral lesions, small avulsion fragments)
• Equivocal plain radiographs

MRI

• Suspected occult ligamentous injury when radiographs appear normal
• Assessment of syndesmotic ligament integrity
• Osteochondral lesion characterization
• Not routine in acute severe injuries

Vascular Studies (if needed)

• If diminished pulses or abnormal capillary refill: urgent Doppler ultrasound or CT angiography
• Ankle-Brachial Index (ABI) if ischemia suspected

Treatment

Immediate/Emergency Management

• Document dorsalis pedis and posterior tibial pulses
• Document sensation (dorsal foot = superficial peroneal; medial/lateral sole = tibial branches)
• ABI if pulses are diminished

• IV opioids + regional nerve block (popliteal sciatic block, if available)
• Procedural sedation for reduction

1. Adequate analgesia or procedural sedation
2. Flex the knee to relax the gastrocnemius
3. Apply longitudinal traction on the heel
4. Supinate and internally rotate the foot (reversing the pronation-external rotation mechanism)
5. Push the talus back medially under the tibial plafond
6. Apply a well-padded backslab (posterior + U-slab) in neutral position

• Repeat neurovascular assessment
• Repeat radiographs to confirm reduction
• Elevation of the limb

Definitive Treatment

Non-Operative Treatment

• Non-displaced, stable injuries only (virtually never a Dupuytren fracture-dislocation)
• Medically unfit patients where surgical risk exceeds benefit

• Short leg cast with ankle in neutral position
• Non-weight-bearing for 6-8 weeks
• Serial radiographs at 1, 2, and 6 weeks to monitor for redisplacement
• Progressive weight-bearing in boot after bony union confirmed
• Physiotherapy

Non-operative treatment of a true Dupuytren fracture-dislocation carries a very high failure rate due to inherent instability. Secondary displacement and malunion rates have been reported as high as 73%.

Operative Treatment (Standard of Care)

• Emergency (within hours): irreducible dislocation, open fractures, vascular injury, progressive neurological deficit, skin compromised
• Urgent (within 24-48 hours): reducible dislocation with intact skin - wait for swelling to subside to a point where the skin wrinkles
• Semi-elective (5-10 days): after soft tissue swelling resolves - optimal soft tissue condition reduces wound complication risk

Surgical Techniques

• Approach: Direct lateral (or posterolateral) approach to the fibula
• Fixation options:
  • Plate and screws (most common) - lateral neutralization plate or posterior antiglide plate with 3.5 mm screws; minimally invasive plating in osteoporotic bone
  • Intramedullary nail (Rush rod, fibular nail) - useful for very distal fractures or osteoporotic bone
  • Lag screws alone - only for long oblique/spiral fractures with sufficient cortical purchase

Post-operative radiograph showing lateral fibular plate fixation with syndesmotic (position) screw - standard ORIF for Weber C / Dupuytren type ankle fracture-dislocation

• Medial malleolus fracture: ORIF with 2 parallel cannulated screws (tension band wire in very small fragments)
• Deltoid ligament rupture: if medial clear space remains wide after fibula fixation - explore and repair the deltoid ligament (primary repair with suture anchor)

• <25% of articular surface and <2 mm displaced - treat conservatively once fibula and syndesmosis fixed
• >25% articular surface or >2 mm displaced - ORIF via posterolateral approach (antiglide plate or cannulated lag screws from anterior-to-posterior)

Posterior malleolus fixation restores approximately 70% of syndesmotic stability and may negate the need for a separate syndesmotic screw.

Post-Operative Care

Complications

Early

• Wound dehiscence / infection - especially if surgery performed through swollen skin
• Neurovascular injury during reduction or surgery (sural nerve, superficial peroneal nerve)
• Compartment syndrome - monitor post-reduction
• Skin necrosis from delayed reduction or tenting
• Malreduction - especially of the fibula (rotation, shortening) and syndesmosis

Late

• Posttraumatic arthritis - most common long-term complication; cartilage injury at time of dislocation predisposes. Risk increases with age.
• Malunion - usually from inadequate fixation or non-compliance
• Syndesmotic diastasis (chronic) - missed or inadequately treated syndesmotic injury
• Reflex sympathetic dystrophy (Complex Regional Pain Syndrome) - higher risk in ankle fracture-dislocations than simple fractures
• Stiffness - particularly plantarflexion/dorsiflexion limitation
• Hardware failure or screw breakage - syndesmotic screws commonly break at the screw-plate junction; this is actually expected and does not necessarily require removal if asymptomatic
• Sural nerve entrapment or neuroma - from lateral approach

Comparison with Related Injuries

Summary Flowchart

SUSPECTED DUPUYTREN FRACTURE-DISLOCATION
              ↓
Neurovascular check → Skin tenting? → YES → IMMEDIATE closed reduction
              ↓
Plain X-ray (AP, Lateral, Mortise)
              ↓
Suprasyndesmotic fibular fracture + medial disruption confirmed (Weber C)
              ↓
CT scan for preoperative planning
              ↓
Is there dislocation? → YES → urgent reduction + backslab, elevate
              ↓
Wait for soft tissue recovery (skin wrinkling sign)
              ↓
ORIF: Fibula → Syndesmotic fixation → Medial side → Posterior malleolus
              ↓
Non-weight-bearing → Progressive rehabilitation → Return to activity