Imaging of growth disturbance in children.

Growth disturbance of the long bones in children is frequently post-traumatic but also occurs because of physeal, epiphyseal, or metaphyseal ischemia. The imaging features of growth arrest depend more on the anatomic site involved than on the cause. The physes of the distal tibia and femur and proximal tibia are disproportionately at risk because of their complex geometry. The central undulation in the distal femur and the bump in the anteromedial physis (Kump's bump) in the distal tibia are the sites of initial physiologic closure and the most frequent areas of premature fusion. The MR imaging features of growth disturbance are characteristic. T1-weighted images show low signal intensity GRL and variable signal intensity bony bridges. On GRE sequences, a bridge appears as low signal intensity interruption in the otherwise high signal intensity physeal cartilage. Physeal widening on GRE and T2-weighted images implies physeal dysfunction without bridge formation. Proton density and T2-weighted images best reveal associated metaphyseal and soft tissue changes. Regardless of the cause, MR imaging exquisitely depicts cartilaginous pathology at the physis. MR evaluation should be considered in patients at high risk for growth disturbance including young children with extensive residual growth potential; those with involvement of particularly vulnerable growth plates; and those with severe, complex fractures.