Pediatric Ankle Fractures

1. Pediatric Ankle Fractures Natasha Holder

2. Outline • Epidemiology • Anatomy • Pathophysiology • Classification • Treatment Options • Prognosis

3. Epidemiology • Distal tibial epiphysis is the second most common site of epiphyseal fracture • 10 to 25% of all physeal injuries • 5% of pediatric fractures • Most occur between ages 10 - 15 y.o. • Boys > girls • Direct and indirect mechanisms Kay et al. JAAOS. 2001, 9:268-278

4. Growth Plate Anatomy • A – Reserve: Extracelluar matrix and quiescent cells • B – Proliferative: Proliferation of chondrocytes with longitudinal growth and stacking of chondrocytes • C – Maturation: synthesis of ECM. Collagen II, IX, XI • D – Hypertrophic: cell division ceases, terminal diferentiation. This is weakest portion of the epiphyseal plate (Zone of Provisional Calcification) • E – Vascular: Vascular capilary loops from metaphysis invades the hypertrophic zone

5. Perichondrial Ring

6. Growth Plate Failure

7. Anatomy of The Ankle • Stable hinge joint (articular congruity, ligaments) • Talar dome narrower posteriorly, more potential for rotation/translation plantarflexedankle

8. Pediatric Ankle Anatomy • All ligamentous structures about the ankle are attached to the epiphyses • Ligaments are stronger than physis • Syndesmosis is rarely injured in children

9. Ligaments of The Ankle Rockwood and Green. Fractures in Children, 7th ED

10. Distal Tibia Physis • 3-4 mm of growth annually • 15-20% of the lower extremity length • 35-45% of tibial length • Closes at age 14 in girls and 16 in boys • Secondary ossification center appears between 6 - 24 months • Medial malleolus begins to ossify between 7 and 8 years of life and usually forms from the an elongation of the main ossific nucleus of the tibia • Originates from ossubtibiale in about 20%

11. Distal tibial physis ossification • Anteromedialundulation: physis separates medial lateral halves (important in understanding fracture patterns) • Over next 18 months, closure progresses central medial  lateral Rockwood and Green. Fractures in Children, 7th ED

12. Distal Fibula • Ossifies at 18-20 months (up to 3 years) • May have accessory os fibulare (1%)

13. Accessory Ossicles • Accessory ossicles of the malleoli are common in skeletally immature • Fuse with the secondary ossification center at skeletal maturity • Need to correlate with point tenderness or bone scan

14. Pediatric Ankle Classification • Salter Harris – 1963 • Dias and Tachdjian – 1978 – modified the Lauge-Hansen classification for pediatric ankle fractures

15. Salter-Harris Thurston-Holland fragment Schnetzler et al. JAAOS, 12007, 15:738-747

16. Salter Harris • Rare types of Salter-Harris fractures include the following: • Type VI - Injury to the perichondral structures • Type VII - Isolated injury to the epiphyseal plate • Type VIII - Isolated injury to the metaphysis, with a potential injury related to endochondral ossification • Type IX - Injury to the periosteum that may interfere with membranous growth

17. Dias-Tachdjian • Dias and Tachdjian CORR 1978 • 71 ankle fractures in children • Classification is proposed based on the position of the foot at the moment of trauma and the direction of the abnormal force • Supination-inversion mechanism most common • Emphasized correlation Salter and Harris • Facilitates closed reduction CORR 1978, 136:230-233

18. Dias-Tachdjian Rockwood and Green. Fractures in Children, 7th ED

19. Diagnosis • History and neurovascular exam • Always consider child abuse, pathological • Radiographs - AP, LAT, Mortise • normal anatomic variants • Stress radiographs • CT scan – to assess articular involvement • MRI

20. Pediatric Ankle sprains • Diagnosis of exclusion • Locate area of tenderness • Often represent missed Salter I ankle fractures • Close follow up

21. Goals of Treatment • Satisfactory anatomic reduction • Avoid physeal arrest • Majority of fractures can be treated non-operatively • Indications for surgical treatment: • Open fracture • Inability to obtain/maintain reduction • Displaced articular/physeal fractures

22. Salter Harris I • Seen with all mechanisms • 15% of distal tibia physeal fractures • Often missed initially • Treatment: • Closed reduction for displaced fractures • Cast treatment for 4-6 weeks • Open reduction rarely indicated • Follow for growth arrest

23. Salter Harris II • Most common fracture type (40%) • Seen with all mechanisms, but commonly the result of supination external rotation injury • Frequently associated with fibula fracture • Thurston-Holland Fragment: metaphyseal spike, usually seen on the distal medial tibia

24. Salter Harris II • Treatment: • Closed reduction for displaced fractures • Cast treatment in LLC for 4-6 weeks • Follow for growth arrest • Open reduction rarely indicated • ORIF for unstable fracture, large metaphyseal component using 3.5 or 4.5 mm

25. Salter Harris III • Account for 25% of distal tibia fractures • Typically occurs in children < 10 • Mechanism of injury is typically supination-inversion • Intraarticular step off • Commonly seen with medial malleolus fractures and Tillauxfractures • Usually produced by medial corner of talus being driven into the articular surface of the medial malleolus

26. Salter Harris III • Treatment: • Closed reduction can be attempted • ORIF for fractures with >2mm residual displacement • Screw fixation is preferable • Screws or threaded k-wires should never be placed across an open physis • Smooth k-wires if physis must be crossed

27. Tillaux fracture • Nearing skeletal maturity 12-14 years (occur during 18 month period where physis closing) 1892

28. Tillaux Fractures • 3 - 5% of all pediatric ankle fractures • Fibula prevents marked displacement/swelling may be subtle • Local tenderness at ant-lat joint line • Mortise view essential

29. Non-displaced Tillaux Fractures • LLC, knee flexed 30, for 4 wks SLWC x 3-4wks • CT scan after cast placement to assure no displacement or intraarticular incongruity • Weekly radiographs in cast for first 3 weeks to assure no displacement in cast • FU xrays obtained every 6 months for 2 to 3 yrs

30. Displaced Tilaux Fractures • displacement (>2mm) • Anatomical reduction • CR achievedLLC • CR unsuccessfulOR for ORIF • k-wires to joystick Tillaux fragment (percutaneously or open) • Fixation with cannulatedscrews, may cross physis • Postop – SLC for 3-4wksSLWC x3wks

31. JuvenileTillaux Fracture-ORIF

32. Salter Harris IV • Account for 25% of distal tibia fractures • Seen with Triplanefractures and with shearing injuries to the medial malleolus • Associated fibular fractures are usually SH I or II • Treatment: • Non-displaced fractures (<1 mm) • Long leg cast followed by short leg walking cast • Close follow up with weekly radiographs • Percutaneous fixation if fracture is unstable • Follow for growth arrest

33. Salter Harris IV • Treatment: • Displaced Fractures (>2 mm) • Anatomical reduction required • Closed reduction under general anesthesia if continued • Open reduction, epiphyseal fixation parallel to growth plate if much growth remaining

34. Salter Harris IV

35. Triplane Fractures • Account for 5-7% of pediatric ankle fractures • Considered transitional fractures • Occur during transition from open to closed physis • Average age 13 • Reported in as young as 10

36. Triplane Fractures • Salter-Harris IV • Components in sagittal, coronal, and transverse planes • Composed of at least 2 fragments • Posterior metaphyseal fragment • Typically lateral epiphyseal fragment

37. 2 part

38. 3 part

39. 4 part

40. Triplane Fractures • Lateral triplane fractures more common than medial • Lateral appear similar to Tillaux on AP • distinguished by SH II or IV fracture on lateral view • Medial have more medial location of epiphyseal and metaphysealfractures

41. Treatment • Nondisplaced: • LLC for 4 weeks  SLWC for2 weeks • Displaced: • Closed reduction for 2 part fractures • IR of distal fragment for lateral, EV for medial • Less successful in 3 and 4 part fractures • CT to assess reduction

42. Treatment • Displaced: • Intra-articular displacement >2mm or physeal displacement >2mm in a child with >2 years of growth left requires ORIF • Anterolateral approach for lateral fractures • Anteromedial approach for medial fractures • Allows visualization of fracture fragments and joint surface

43. Treatment • Goal is to restore articular congruity to maximize outcome • Fracture configuration or surgeon preference determines whether metaphyseal or epiphyseal fragment is fixed first • Cannulated screws allow accurate placement and minimize incidental physeal damage

44. The Complex Triplane • Uncommon, multilevel injury • Associated ipsilateraltibial shaft fracture • CT scanning in invaluable to confirm reduction Jarvis et al. JOT 2001, 51: 714-716

45. The Complex Triplane Jarvis et al. JOT 2001, 51: 714-716

46. Salter Harris V • Account for 1% of distal tibia fractures • Crush injury to physis • No associated displacement • Diagnosis made with follow-up xrays revealing premature physeal closure • No specific treatment recommendations formulated, treatment directed primarily at sequelae of growth arrest

47. Adolescent Pilon Fracture • Relatively rare • High energy trauma • Axial compression, forced dorsiflexion, violent external rotation • Injuries can be associated with severe soft tissue swelling and edema • Similar to the treatment in adults with these injuries, management of the soft tissues is critical to prevent complications of skin loss, infection, wound healing problems, etc • Average age 15 years • Radiographs tib/ankle/hindfoot • CT Letts et al. J Ped Ortho 2001, 21:20-26

48. Letts et al. J Ped Ortho 2001, 21:20-26

49. Adolescent PilonFractures Letts et al. J Ped Ortho 2001, 21:20-26

50. Adolescent PilonFractures • First series of adolescent pilon fractures • Fewer associated injuries • Treatment objectives: • Anatomic reduction of the articular surface and physis • Stable fixation • Early mobilization