A blog by Antoni Caserta.
Children fall; they twist their ankles all the time, but do you refer for imaging? If you do, are the xrays generally negative for fracture, and ultrasounds negative for soft tissue damage? But the child is still limping, the ankle looks like a balloon and she screams when you go anywhere near the joint line.
In a growing child, it is likely that the surrounding soft tissue is stronger than the growth plate, metaphysis and epiphysis of the tibia and fibula. There is the theory that these surrounding osseous structures will likely injury prior to the attaching ligaments. When edema, bruising, inability to weight bear and joint line tenderness is still present but imaging is NAD, one needs to consider a injury to the growth plate, in particular a Salter-Harris Fracture Type 1.
For the growth of the long bones, the growth plate, a “translucent, cartilaginous disc separating the epiphysis from the metaphysis” (1) has multiple layers within it where a series of metabolic events allow ossification to occur.
Growth plate injuries can be classified using the Salter-Harris Fracture types. A Salter Harris Fracture Type 1 is a transverse fracture through the growth plate that can be either displaced or undisplaced (2).
Below is a summary of the 5 most common Salter-Harris Facture types.
Type 1: physis injury
Type 2: physis and metaphysis
Type 3: physis and epiphysis
Type 4: physis, epiphysis and metaphysis
Type 5: compression through the physis
The Royal Children’s Hospital Melbourne provides clinical practice guideline on their website for the treatment of distal tibia and/or fibular physeal fractures for ED staff. In the case of an isolated undisplaced distal fibular physeal Salter-Harris fracture type 1 or 2 it is advised that ED management should include below knee casts and non-weight bearing with a follow up with orthopaedics within 7-10 days to be accompanied by follow up xrays.
Does damage to the growth plate affect the growth of that leg?
This will likely depend on the type and the early treatment of the injury, age and location of the injury but generally Type 1 undisplaced injuries resolve if treatment is implemented as soon as possible. Remembering your rehab for an ankle injury should still be implemented as per normal for the age group.
2. Salter RB, Harris WR. Injuries involving the epiphyseal plate. J Bone Joint Surg Am. 1963; 45(3):587-622.
3. Mubarak SJ, Kim JR, Edmonds EW, Pring ME, Bastrom TP. Classification of proximal tibial fractures in children. J Child Orthop. 2009 Mar 17.
4. Brown JH, DeLuca SA. Growth plate injuries: Salter-Harris classification. Am Fam Physician. 1992 Oct. 46(4):1180-4.