The Pediatric Triplane Ankle Fracture

Mitchell Goldflies, M.D.

Overview

• • • • • • Introduction History Pathophysiology Diagnosis Treatment ▫ Closed ▫ Open Discussion

Pediatric Triplane Ankle Fracture

• Complex fracture • Difficult to define according to Salter-Harris classification

Pediatric Triplane Ankle Fracture

con’t • • • • Meets three-plane criterion Represents 5 – 10% of pediatric intra-articular ankle injuries Presents in children age 12 to 15 years of age ▫ Higher incidence among boys Treatment: ▫ Nondisplaced triplane/extra-articular injuries:  Immobilization in long leg cast ▫ Displaced:  Open reduction and internal fixation

History

• Lynn ▫ 1972 ▫ Termed injury pattern distal tibial epiphyseal ▫ Produced by combination of mechanisms and characteristic asymmetric pattern of closure

History

con’t • Marmor ▫ Three fragments requiring cortical screw fixation found

Pathophysiology

• Susceptible during transitioning skeletal maturity: ▫ Girls:12 to 14 years of age ▫ Boys:13 to 15 years of age ▫ Not younger then age 10 or older than 16.7 years

Pathophysiology

con’t • Sustain injury during athletic activity or consequence of fall ▫ Increased incidence among skateboarding, roller skating, inline skating, ice skating, and snowboarding

Pathophysiology

con’t

• Three fracture fragments: ▫ Fracture fragments mimic the juvenile Tillaux fracture  posterior and medial fragments with a metaphyseal spike, and the tibial metaphysis ▫ Fibular fracture in approximately 50% of triplane ankle fractures

Pathophysiology

con’t

• Two fracture fragments: ▫ Lateral:  coronal fragment posterolateral ▫ Medial:  coronal fragment posteromedial  intra- and extra-articular intramalleolar variants have been described

Pathophysiology

con’t

• Quadruple fracture fragments: ▫ External rotation and vertical compression proposed as mechanism for injury

Diagnosis

• Radiographs ▫ Do not consistently demonstrate the number of fracture fragments ▫ Anterposterior radiographs:  triplane fracture has appearance of Salter-Harris type III ▫ Lateral radiographs:  triplane fracture has appearance of Salter-Harris type II

Diagnosis

con’t • CT Scans ▫ Used to:    identify configuration of the facture aid in evaluating residual displacement, aid in preoperative planning ▫ Three-point star configuration noted

Diagnosis

con’t • MRI ▫ Used for:   complex fractures fractures of uncertain classification based on radiographs

Diagnosis

con’t

• Brown et al study ▫ 51 children aged 10 to 17 years ▫ Most frequent: two-fragment pattern with medial epiphyseal extension (33/51 children) ▫ Three-fragment patterns seen ▫ Extension to medial malleolus evident (12 children)

Treatment

• • Selection based on: ▫ Fracture is nondisplaced or displaced ▫ Magnitude of displacement ▫ Intra- versus extra-articular nature of injury Fractures with >2mm intra-articular step-off require reduction (closed or open)

Treatment – Closed

• Nondisplaced triplane and extra-articular fractures (<2mm displacement): ▫ Managed with long leg cast ▫ Closed reduction performed under general anesthesia with axial traction on the ankle and internal rotation of the foot ▫ Reduce fibular fracture first ▫ Medial fractures:   external rotation foot position ▫ Lateral fractures: internal rotation foot position

Treatment – Closed

con’t

• • • Nondisplaced triplane and extra-articular fractures (>2 mm displacement): ▫ Requires open or closed reduction Nondisplaced triplane and extra-articular fractures (>3 mm displacement): ▫ Closed reduction not successful Extra-articular variants ▫ Nonsurgical management

Treatment - Open

• ORIF ▫ Anterolateral approach – lateral fractures ▫ Anteromedial approach – medial fractures ▫ Surgical indications:   Fracture displacement >3 mm Failure to achieve adequate reduction (>2 mm intra articular step off)

Treatment – Open

con’t • Arthroscopic reduction and internal fixation of two-part triplane fractures ▫ Advantages:    surgical trauma reduced clearer identification of fracture fragment orientation allows for direct visualization of joint congruity and accurate reduction

Treatment – Open

con’t

Discussion

• • • Distal tibial physis ▫ 50% of tibial growth ▫ 4 to 6 mm of longitudinal growth per year Surgical treatment as measure to prevent residual articular incongruity and long-term degeneration Most patients return to preinjury activity levels

Conclusion

• Unique fracture configuration • Not consistent with Salter-Harris classification • • • Results from asymmetric closures of distal tibial physis and combination of mechanisms Proper diagnosis and treatment requires: ▫ Evaluation/awareness of associated injury ▫ Understanding of fracture patterns possible ▫ Radiographs and CT necessary to evaluation conduct preoperative planning ▫ Rational treatment approach Optimal treatment: ▫ Reduction to within 2mm of anatomic

Questions?

Resources

• Journal of the AAOS. Vol. 15. No. 12. pp. 738 – 745.