FIGURE 111.45 The ligaments of the knee Proximally, both collateral ligaments attach to the epiphysis, whereas distally they attach to the tibia and fibula below the tibial epiphysis Tibial Tubercle and Spine Fractures Avulsion of the tibial spine occurs with hyperflexion and presents with pain and refusal to bear weight in the presence of hemarthrosis Soft tissue injuries, including meniscal or articular cartilage injury, often occur with tibial spine avulsion fractures Radiographs should be obtained, which may reveal findings ranging from minimal elevation of the anterior portion of the tibial spine (best seen on lateral views) to complete separation ( Fig 111.46 ) The extremity should be splinted in extension If the child is in significant pain, arthrocentesis of the hemarthrosis may be performed, although this must be balanced against the risk of infection from the procedure Orthopedics should be consulted for further management Incomplete separations may be managed with closed reduction, while complete avulsion requires open repair