Fractures of the tibial eminence, or tibial spines, are a type of knee injury often treatment by a sports medicine knee doctor. Tibial eminence fractures are bony avulsions of the anterior cruciate ligament (ACL) from its attachment to the tibia. Tibial eminence fractures are fairly rare and account for about 2-5% of pediatric knee injuries. These fractures occur most commonly in children between ages 8-14, although they occasionally occur in adults. These fractures often occur from hyperextension or rapid deceleration of the knee, similar to many ACL injuries. It is the traction on the ACL that leads to the avulsion injury. This is often seen with soccer, rugby, football, skiing, and other sports.
Tibial spine fractures are classified by the degree of displacement. Type I fractures are non- or minimally-displaced. This means the fracture is in great alignment and has not pulled away from the bone. Type II fractures show some lifting of 1/3 to 1/2 of the tibial eminence. The posterior “hinge” remains in place. Type III fractures are completely displaced. Type IIIA fractures have no malrotation, while Type IIIB fractures are rotated so the cartilage surface now faces the bony fracture site. Type IV fractures are displaced and comminuted.
Treatment is usually dictated by the degree of displacement. Type I fractures can be treated without surgery. This involves casting or bracing with the knee in full extension, or near full extension, for 3-6 weeks. Occasionally the knee is aspirated to remove the hemarthrosis (bloody swelling in the knee), which can help with symptoms. Isometric quad exercises are started immediately. Repeat x-rays are obtained through the course of treatment to make sure the fracture does not displaced (especially noticeable on the lateral x-ray). After adequate time for healing (4-6 weeks), more aggressive physical therapy is started to restore range of motion and strength.
Treatment of Type II fractures is somewhat controversial, although most Type III fractures are treated with surgeries. Some Type II fractures can be treated successfully with out surgery. Occasionally a closed reduction of the knee and casting is successful. The risk of treating a Type II fracture non-operatively is that meniscus or cartilage may become entrapped in the fracture site and prevent healing. Multiple fixation techniques have been described when surgery is needed. Many times, fixation can be done arthroscopically (through small incisions with assistance of an arthroscope).
Postoperative & Rehabilitation
Postoperative protocols can vary. In general, the knee is immobilized in near extension for 2-3 weeks. At that point, range of motion exercises are initiated. The main challenge after surgery is to prevent arthrofibrosis (stiffness of the knee) while allowing the repair to heal. Physical therapy is usually initiated at 2-3 weeks after surgery, and focuses on restoring range of motion and improving muscle strength.