We studied the cases of nine adolescent patients with a Salter-Harris
Type-III fracture of the lateral portion of the distal tibial epiphysis
(sometimes called the juvenile Tillaux fracture) and eight patients with a
triplane fracture of the distal tibial epiphysis. The mechanism of both
injuries was postulated to be external rotation of the foot on the leg.
There were both two-fragment and three-fragment triplane fractures in the
series. The three-fragment triplane fractures occurred in younger patients,
and surgical treatment was more frequently administered. The pattern of
closure of the distal tibial growth plate in the adolescent strongly
influenced the type of fracture.