Modeling and analysis of proximal tibial growth plate fractures in adolescents

Today, children and adolescents are participating heavily in organized athletics year-round. Each year, approximately one third of these children will experience a serious injury requiring a doctor´s or hospital visit. Physeal, or growth plate fractures, are one such type of overuse injury commonly seen in adolescents. At the knee joint, injuries in adolescents occur most often in the proximal region of the tibia as opposed to the middle or distal thirds of the tibia, or in the soft tissues of the joint, as seen in adults. While the exact reasons for this difference have not been directly and definitively quantified, several hypotheses have been suggested. They include differences in movement strategies, changes in limb inertial and material properties, and the timing of these changes in relation to one another. This work aims to compare the changes in and effects of inertial properties of the lower leg on forces transmitted through the patellar tendon, and tibiofemoral contact before, during, and after puberty. Using Kane´s method of dynamics in conjunction with an isometric knee extension study, patellar tendon length and dynamometer force were found to have the greatest effect on proximal tibial forces. These results were then extended to a finite element analysis to load tibial models and investigate changes in stress and strain at the proximal tibia.