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Pediatric Ankle & Foot Fractures. Steven Rabin, MD Revised: March 2011 Original authors (2004): Laura Phieffer, MD & Steven Frick, MD Revised (2006): Steven Frick, MD. Pediatric Ankle Fractures. Epidemiology. 2nd most common site of physeal fractures in children
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Pediatric Ankle & Foot Fractures Steven Rabin, MD Revised: March 2011 Original authors (2004): Laura Phieffer, MD & Steven Frick, MD Revised (2006): Steven Frick, MD
Epidemiology • 2nd most common site of physeal fractures in children • Most occur between ages 8 - 15 y.o. • Boys > girls • Direct and indirect mechanisms of injury
Anatomy • All ligamentous structures attach distal to the physis • Ligaments are stronger than physis and bone • Physeal injury more common than ligament injury • Anterior Tibio-fibular ligament important in transitional fractures when the physis is closing
Ankle Anatomy • Distal tibia ossification center appears between 6 - 24 months • Distal fibula ossification center appears between 9 - 24 months • Medial malleolar extension appears at about 7 years
Physeal Closure • Distal tibia physis closes: • About age 12-15 yrs girls • About age 13-17 yrs boys • Medial malleolus extension appears ~10 yrs • Asymmetric closure over ~18 months • Tibia physis closes in center first then medially and posteriorly. • Anterolateral portion of physis is the last to close • Closure of the distal fibula physis follows distal tibia physeal closure by ~12-24 months
Age / Fracture Pattern Spiegel P, et al. Epiphyseal fractures of the distal ends of the tibia and fibula. J Bone Joint Surg Am. 1978;60(8):1046-50.
ClassificationAnatomic • Salter-Harris • High interobserver correlation • Correlated with outcomes
Classification - Ankle Fractures • Mechanism of injury: Dias L, Tachdjian M. Physeal injuries of the ankle in children: classification. Clin Orthop Relat Res. 1978;136:230-3.
Diagnosis - Ankle Fractures • Direct/indirect mechanisms • Acute/subacute • May have subtle exam findings • Differentiate sprain from non-displaced fracture by location of tenderness • (Pain over the physis/bone = physeal injury) • (Pain over the soft tissues = sprain)
Imaging of Ankle Fractures • Radiographs - AP, LAT, Mortise • know normal anatomic variants • Stress radiographs • CT scan – to assess articular involvement • MRI – role not well defined • Bone Scan – if in doubt about an accessory ossification center vs. an acute fracture
Accessory Ossification Centers – Smooth Borders • Accessory ossification centers usually appear between ages of 7 to 10 yrs • Fuse by skeletal maturity • Medial (os subtibiale) in 20% of patients • Lateral (os subfibulare) in 1% of patients
Treatment Considerations • Location of fracture • Mechanism of injury • Degree of displacement • Age of child (how much growth remains) • Distal tibia physis contributes: • 3-4 mm growth per year • 35-45% of overall tibial length
Salter-Harris Type I Fracture • Typically occur in younger pts • Seen with all mechanisms (SI, SPF, SER, PER) • Often missed initially (dx “sprain”): • Physis weaker than ligaments so physeal injury is more common than a sprain • Xrays • Acute – often normal except for soft tissue swelling over physis • Subacute - reveal widening of physis- healing
Salter I Distal Tibia Fractures: Treatment • Less than 3 mm displacement • Cast • 4-6 weeks depending on the patient’s age • Greater than 3 mm displacement • Gentle closed reduction and casting • Usually require anesthesia • If interposed soft tissue, must be removed • If unstable, pin fixation may be needed. • More likely to be unstable if fibula also fractured • Follow x-rays for 6-12 months to evaluate for premature physeal closure
Salter I Fracture Distal Tibia • Salter I fracture of the distal tibia (with metaphyseal fibula fracture) • Treated with closed reduction and pin fixation
Salter-Harris Type II Fractures • Most common distal tibia Fx type • Seen with all mechanisms (SI, SPF, SER, PER) • Mechanism deduced by • Direction of displacement of the tibial epiphysis, • Type of associated fibula fx • Location of metaphyseal spike
Salter-Harris Type II fractures: Treatment • Non-displaced fractures • Short leg cast (SLC) for 3 weeks • Then walking SLC for 3 weeks • Displaced fractures • Avoid repeated attempts at reduction • If unstable consider a long leg cast for 2-3 weeks, otherwise a short leg cast for 3-4 weeks then a short leg walking cast for 2-3 weeks (depending on age) • Open reduction infrequently indicated • Follow for growth arrest
Salter II Fracture of the Distal Tibia • Salter II fracture of the distal tibia • treated with closed reduction and cannulated screw fixation
Salter-Harris Type I & II fxs • If reduction is incomplete, how much residual displacement is acceptable? • Carothers and Crenshaw (1955) • “accurate reposition of the displaced epiphysis at the expense of forced or repeated manipulation or operative intervention is not indicated” Carothers C, Crenshaw A. Clinical significance of a classification of epiphyseal injuries at the ankle. Am J Surg. 1955;89(4):879-89.
Salter-Harris Type I & II fxs • If reduction is incomplete, how much residual displacement is acceptable? • Spiegel (1978) • correlated Salter-Harris classification with risk of shortening, angular deformity and joint incongruity • recommended “precise anatomical reduction” Spiegel P, et al. Epiphyseal fractures of the distal ends of the tibia and fibula. J Bone Joint Surg Am. 1978;60(8):1046-50.
Salter-Harris Type I & II fxs • Differing opinions regarding indication for open reduction for interposition of periosteum => widening with minimal angulation • Kling (1984) • Phieffer (2000)- Animal model • Barmada (2005) believes interposed periosteum leads to growth disturbance -Kling T, Bright R, Hensinger R. Distal tibial physeal fractures in children that may require open reduction. J Bone Joint Surg Am. 1984;66(5):647-57. -Phieffer et al. Effect of interposed periosteum in an animal physeal fracture model. Clin Orthop Relat Res. 2000;376:15-25. -Barmada A, Gaynor T, Mubarak SJ. Premature physeal closure following distal tibia physeal fractures: a new radiographic predictor. J Pediatr Orthop. 2003;23(6):733-9.
Closed reduction with incomplete reduction because of interposed soft tissues – removed at ORIF
Salter-Harris Type I & II fxs • Displaced subacute (>7-10 days out) fxs • Residual displacement may have to be accepted • If growth does not sufficiently correct malunion, corrective osteotomy performed
Salter-Harris Type III & IV fxs • Mechanism of injury similar for both fx patterns (typically supination-inversion) • Usually produced by medial corner of talus being driven into the junction of distal tibial articular surface and the medial malleolus • Can see central and lateral fx patterns
Salter-Harris Type III & IV fxs • Treatment and prognosis are similar • Anatomic restoration of the articular surface is a high priority • Medial pattern appears to be at higher risk for developing partial growth arrest and subsequent varus deformity -Spiegel P, Cooperman D, Laros G. Epiphyseal fractures of the distal ends of the tibia and fibula. J Bone Joint Surg Am. 1978;60(8):1046-50. -Kling T, Bright R, Hensinger R. Distal tibial physeal fractures in children that may require open reduction. J Bone Joint Surg Am. 1984;66(5):647-57. -Caterini R, Farsetti P, Ippolito E. Long-term followup of physeal injury to the ankle. Foot Ankle. 1991;11(6):372-83.
Salter-Harris Type III & IV fxs • Non-displaced fractures (<1 mm) • Cast for 3-4 wks => SLWC x 3 wks • May need CT after cast placement to assess displacement • Follow with x-rays in cast to assure no displacement • Percutaneous fixation is an option • Follow for growth arrest
Salter IV Minimally Displaced Distal Tibia Fracture *Fixation avoids physis
Salter-Harris Type III & IV fxs • Displaced fractures (>2 mm) • Require Anatomic reduction • Closed reduction under general anesthesia • If continued > 2 mm displacement => open reduction • Open reduction with epiphyseal fixation parallel to growth plate if possible, especially if significant growth remaining • Postop: Cast (NWB) for 3-4 wks => SLWC x 3 wks • Follow for growth arrest: 15% incidence of growth arrest even with anatomic reduction
Salter III Injury- Closed reduction with percutaneous internal fixation
Salter-Harris Type III & IV fxs • Subacute displaced fxs • Accept up to 2 mm displacement • Greater than 2 mm displacement • Goal to restore joint congruity • Recommend reduction regardless of time from injury • Debridement and interposition graft, if necessary
Delayed diagnosis Salter IV medial malleolus fracture in 6 yr multi-trauma patient • Initial radiographs 15 days out from injury
ORIF 16 days after injury • Anterior approach
Note Harris growth line parallels physis and increased distance between markers – normal growth • Nine months post-operative
Salter-Harris Type V fxs • Crush injury to physis • No associated displacement • Diagnosis made with follow-up xrays revealing premature physeal closure • Treatment directed primarily at sequelae of growth arrest
High energy injuries to distal tibia • Uncommon • Severe injury to distal tibial articular surface – poor prognosis • Restore articular surface, if possible • Length and alignment – bridging external fixation can be helpful
High energy distal tibia fracture/subluxation 11 year old female in MVC
CT scan demonstrates significantly comminuted articular surface and anterior subluxation of talus
Intraop views – bridging external fixation and ORIF with pin fixation
12 Year Old – High Velocity GSW – loss of tibial epiphysis/anterior soft tissues/tendons - bridging external fixator- latissimus free flap-ankle fusion
“Transitional” Fractures • Fractures occurring during asymmetric closure of distal tibial physis • Triplane fx • Fracture appears to be in multiple planes • May be 2, 3 or 4 part fractures • Tillaux fx • Fracture of the anterolateral epiphysis
“Transitional” Fractures • Triplane fx • Tend to be seen in younger pts than those with Tillaux fx • More displacement/swelling • Appear as Salter III on AP view and Salter II on lateral view • Treatment decisions usually based on articular displacement • CT scan often helpful
Triplane Fractures • Combination of Salter II and III fractures: usually near end of growth (Complex type IV fracture) • Anterior epiphseal fracture with large posteriomedial metaphyseal fragment…fibula may also be fractured
Triplane FracturesResults • Overall results are good following adequate reduction • Von Laer (1985) • Clement and Warlock (1987) - Good early results • Erlt (1988) - Decline in results over time -von Laer L. Classification, diagnosis, and treatment of transitional fractures of the distal part of the tibia. J Bone Joint Surg Am. 1985;67(5):687-98. -Clement D, Worlock P. Triplane fracture of the distal tibia. A variant in cases with an open growth plate. J Bone Joint Surg Br. 1987;69(3):412-5. -Ertl J, Barrack R, Alexander A, VanBuecken K. Triplane fracture of the distal tibial epiphysis. Long-term follow-up. J Bone Joint Surg Am. 1988;70(7):967-76.
Triplane Fractures • Non-displaced • Cast (NWB) 3-4 wks, then SLWC x 3-4 wks • Monitor in cast to assure no displacement • FU x-rays every 6-12 months for 2 to 3 yrs to assess for growth arrest
Triplane Fractures • Displaced Triplane Fractures (>2 mm) • Anatomic reduction required • If closed reduction successful • Cast: consider a long leg cast with 30 of knee flexion and foot internally rotated, if unstable • If closed reduction unsuccessful => ORIF • Reduction/internal fixation done in step-wise fashion with small fragment or 4.0 cannulated screws • Postop - SLC x 3-4 wks, then SLWC x 3 wks