Causes / typical injury mechanism: Proximal tibia epiphyseal fractures often occur from high-energy impacts to the knee, such as a fall from a height, a motor vehicle crash, or while playing a sport that involves significant impact on the knee.
Classic history and presentation: Typically, children and adolescents present with pain, swelling, and difficulty bearing weight on the affected leg. They will likely report a recent incident or significant injury to the knee.
Prevalence: Proximal tibia epiphyseal fractures are relatively uncommon, only accounting for 0.5-3% of all epiphyseal injuries.
- Age – Proximal tibia epiphyseal fractures typically affect older children and adolescents (ages 10-17 years) whose growth plate is still open and vulnerable to injury.
- Sex / gender – All sexes are affected based on exposure to activities that increase risk to fracture.
Pathophysiology: A high-energy impact to the knee joint that causes either a varus or valgus knee deformity can cause a separation between the epiphysis and metaphysis of the tibia. Because this separation occurs through the growth plate – made up of cartilage responsible for bone growth – this type of fracture can lead to impaired growth of the tibia. Moreover, this can cause damage to the popliteal artery as well as nearby nerves.
Grade / classification system: The Salter-Harris classification is used to describe physeal injuries in children.
- Type I: Fracture through the physis, usually displaced (> 50%) due to the buttress effect of the tibial tubercle and fibula.
- Type II: Fracture through the physis and exiting through the metaphysis, usually displaced (> 67%).
- Type III: Fracture through the physis and exiting through the epiphysis.
- Type IV: Fracture through the physis, metaphysis, and epiphysis.
