Talar dome is more broad anteriorly than posteriorly, therefore more translation + rotation is permitted in plantarflexion
Anterior Inferior TaloFibular (AITF)ligament attaches to distal tibial epiphysis & is important in the pathomechanics of transitional fractures (Tillaux + Triplane)
TibioFibular syndesmosis allows fibular motion during dorsiflexion + plantarflexion
Distal tibial physis provides 3-4mm growth per year (35-40% tibial length or 15-20% lower limb length)
In general terms, distal tibial closure is completed by age 14 years in girls + 16 years in boys
Closure of distal tibial physis progresses from central → medial → lateral over 18 months
Secondary ossific nucleus
Distal tibial epiphysis appears 6-24 months
Medial malleolus 7-8 years (separate ossification centre = os subtibiale in 20% population)
Distal fibula 18-20 months (separate ossification = os fibulare in 1% population)
Classification
Salter-Harris
Lauge-Hansen
Dias + Tachdjian
Diagnosis
Multitrauma patient assessment according to EMST guidelines
primary survey
secondary survey
Examination
pulses (Doppler study)
capillary refill
sensation
motor assessment
Xrays
AP + lateral + mortise
CT
transitional fracturess
MRI
osteochondral fragments
Treatment
Salter-Harris 1+2
Type 1 = 15% + type 2 = 40% distal tibial fractures
Type 2 fracture
extends through zone of hypertrophy then exits through metaphysis to produce Thurston-Holland fragment
Attempt reduction only once or twice to minimise physeal injury
10˚ angulation produces ↓tibiotalar contact area + ↑tibiotalar contact pressure
Growth disturbance lines on Xray
are common post fracture & should be parallel to the physis
Absent or angled lines = growth arrest
Partial arrest = angular deformity + leg length discrepancy
Complete arrest does not produce angular deformity but relative fibula overgrowth may proceed
anterolateral pattern is a function of the order of distal tibial physeal closure
May require ORIF via anterolateral approach
Salter-Harris 4
Type 4 = 25% distal tibial fractures
are seen with triplane & shearing medial malleolar fractures
Triplane fractures
generally occur at age 13 years
Posterior metaphyseal fragment + lateral epiphyseal fragment
CT for comminuted fractures
ORIF
to restore articular congruity.
Avoid elevating perichondral ring
Salter-Harris 5
Type = 1% distal tibial fractures
Compressive force across germinal layer of physis. Physeal arrest can produce angular + leg length discrepancy
Complications of Ankle Fractures
Growth Arrest
Most common after Salter-Harris 3+4
ORIF is associated with less articular incongruity, physeal arrest, late arthritis compared with closed reduction
Near skeletal maturity perform epiphyseodesis of remaining physis provided no angular deformity present as distal tibia grows only 3-4mm per year + distal fibula epiphyseodesis to prevent lateral impingement
In younger children physeal bar resection as delineated on MRI
