From the Guidelines
A knee avulsion fracture is a serious injury that occurs when a tendon or ligament pulls a small piece of bone away from the main bone structure at its attachment site, requiring prompt and proper treatment to prevent long-term morbidity and mortality, and to improve quality of life. This type of fracture typically happens during sudden, forceful movements that put extreme stress on the knee joint, such as during sports activities that involve jumping, pivoting, or sudden direction changes 1. Common locations for knee avulsion fractures include the tibial spine (where the anterior cruciate ligament attaches), the tibial tuberosity (where the patellar tendon attaches), or the margins of the patella.
Some key points to consider in the diagnosis and treatment of knee avulsion fractures include:
- The use of ultrasound (US) as a diagnostic tool, which has been shown to be highly accurate in diagnosis of partial-thickness and full-thickness quadriceps tendon tears, with sensitivity and specificity approaching 100% 1.
- The importance of early detection and treatment, as delayed treatment can lead to increased morbidity and mortality, and decreased quality of life.
- The need for individualized treatment plans, as the size of the bone fragment and the degree of displacement can vary greatly between patients, and treatment should be tailored to each patient's specific needs.
Treatment options for knee avulsion fractures include:
- Conservative treatment, such as rest, ice, compression, elevation (RICE protocol), immobilization with a brace or cast for 4-6 weeks, and gradual physical therapy, which is often effective for small, non-displaced avulsion fractures.
- Surgical fixation, using screws, pins, or sutures to reattach the bone fragment, which is often necessary for larger fragments or those with significant displacement (typically more than 2-3 mm) 1.
It is essential to prioritize the patient's quality of life and to minimize morbidity and mortality when treating knee avulsion fractures, and to use the most recent and highest quality evidence to guide treatment decisions, such as the study by Klos et al 1, which showed a higher prevalence of Segond avulsions fractures on US studies than previously reported in literature on the MRI or radiography.
From the Research
Definition of Knee Avulsion Fracture
- A knee avulsion fracture is a type of injury where a fragment of bone is pulled away from the main bone due to a sudden contraction of a muscle or tendon 2, 3, 4, 5.
- This type of fracture can occur in various parts of the knee, including the tibial tubercle, tibial spine, and patella.
Types of Knee Avulsion Fractures
- Tibial tubercle avulsion fractures (TTAF) occur when the tibial tubercle is pulled away from the tibia due to a sudden contraction of the quadriceps muscle 4.
- Tibial spine avulsion fractures (TSAF) occur when the tibial spine is pulled away from the tibia due to a sudden contraction of the anterior cruciate ligament (ACL) 5.
- Patellar avulsion fractures occur when the patella is pulled away from the femur or tibia due to a sudden contraction of the quadriceps muscle or patellar tendon 6.
Treatment of Knee Avulsion Fractures
- Treatment of knee avulsion fractures can be conservative or surgical, depending on the severity of the injury and the patient's overall health 2, 3, 4, 5, 6.
- Surgical treatment may involve open reduction and internal fixation (ORIF) or arthroscopic surgery to repair the avulsed fragment and restore knee function.
- Postoperative rehabilitation is crucial to restore knee range of motion and strength, and to prevent complications such as knee stiffness and arthritis 4, 5.