Knee and lower leg fractures in children are common injuries and they usually involve the growth plate cartilage. The risk of blood vessel and nerve injury as well as compartment syndrome (a condition where extreme swelling causes closure of the small blood vessels and results in muscle death) is extremely high in children and emergency unit assessment as well as immediate fracture reduction and immobilisation is required as a rule. Orthopaedic review is mandatory in order to manage these complications if they occur. If these fractures are not accurately reduced and held in position with screws or wires, there is a significantly higher risk of growth abnormality developing at the knee, which will result in a skew leg and rapid onset osteoarthritis in later life. While plaster cast immobilisation is sometimes adequate, there are significant problems with this, not least of which the fact that if the child swells into the plaster cast, he or she may develop a compartment syndrome.
Anterior cruciate ligament (ACL) injuries also occur in children, however, they usually cause a “pull-off” (avulsion) fracture inside the knee. Depending on the severity, these injuries may be treated with a brace, but sometimes surgery is required. If these injuries are not picked up, the child will often develop a block to knee extension, resulting in significant disability. Delayed surgery for these conditions unfortunately has less good outcomes.
Injuries to the meniscus in children is rare, and if it does occur, it is usually related to a abnormally developed “discoid” meniscus. An MRI scan will be used to diagnose these injuries and keyhole (arthroscopic) surgery with a procedure specifically tailored towards the type of injury would then be carried out. Children have a much higher healing potential and the meniscal tears are usually repaired, if possible.
Fractures of the lower leg (tibia) in children may often be managed in a plaster cast or a brace. The immediate risks and the suggested management, as discussed above also apply to these fractures.
