The knee is a joint where the large femur (thigh bone) connects to the tibia (leg bone). It’s very vulnerable to injury and knee pain, especially in children and adolescent athletes.
Bony knee anatomy
The knee joint is made of three bones: the femur, tibia and fibula. The fibula is on the outer portion of the leg bone. Many ligaments and muscles attach here, but it doesn’t contribute much to the knee otherwise.
The patella (knee cap) rests on the lower end of the femur bone and is embedded in the quadriceps tendon, making it stronger.
There are bony outgrowths of the tibia that deserve special attention. The first is the tibia spines, which serves as the attachment site of the anterior cruciate ligament (ACL). While adolescents and adults tend to get ACL ruptures, younger children are more likely to break the bone than tear the ligament.
The second bony outgrowth is the tibia tubercle. This is the bump that resides on the front of the tibia bone approximately one to two inches below the knee cap. The large patella tendon inserts into this outgrowth and is very vulnerable to both fractures as well as chronic pain due to overuse, such as with running and jumping.