ACL injuries in young athletes

The Anterior Cruciate Ligament (ACL) is one of the four major ligaments in the knee. The ACL ligament connects the tibia (shin bone) to the femur (thigh bone) and keeps the knee stable by preventing the lower leg from shifting forward when walking, running and jumping/landing.

Image of Anterior Cruciate Ligament (ACL) Injuries in Young Athletes 


The three most common mechanisms of ACL injury are:

  • Direct contact from a hit or blow to the knee or lower leg
  • Change in direction or a sudden stop resulting in twisting or hyperextension of the knee
  • Landing incorrectly

Any child can sustain an ACL injury, however, those who play contact sports have the highest risk for this injury. Girls are 2-8 times more likely than boys to suffer a torn ACL. Some experts believe this is partly due to the differences between girls’ and boys’ bodies. Another reason girls face a higher risk for a torn ACL is due to a natural tendency to jump and land with poor mechanics.

Signs & Symptoms

While patients may have different symptoms after an ACL injury, common symptoms include:

  • Hearing or feeling a “pop” sound or sensation in the knee
  • Swelling and pain over the knee
  • Decrease in knee range of motion
  • Difficulty with weight bearing
  • Sensation of “shifting” of the knee when walking


If it is determined that there is a tear of the ACL, the typical recommendation is a surgical reconstruction of the ligament to restore stability and help prevent injury to other structures in the knee. There are multiple methods for ACL reconstruction – including physeal sparing, hamstring auto graft and patellar tendon bone-tendon-bone auto graft. The age of the patient, stage of skeletal maturity, and participating sport should all be considered when deciding the best surgical option.

If a young athlete has open growth plates, they may not be able to undergo the same ACL reconstruction surgery as an adult patient with the same injury. Such surgery could result in permanent damage to a growth center of the knee, so other surgical solutions must be considered.

At your first visit

If you suspect an ACL injury, the initial evaluation will include meeting several members of our team to obtain a comprehensive history and medical exam. Imaging studies such as x-rays or an MRI may be ordered as well.

Once an ACL injury is confirmed, you will schedule a consultation appointment with one of our orthopedic sports surgeons to review imaging studies, discuss surgery and reconstruction options, learn about the recovery process and schedule the surgery.

Contact us

If you are concerned about a possible ACL injury, call us at (414) 607-5280 to schedule an appointment with one of our sports medicine or orthopedic specialists.


Greenfield Clinic
Delafield Clinic

Call us

To speak with a sports medicine expert or request an appointment, call:

(414) 604-7512

Licensed athletic trainers and nurses are available 8 a.m. to 4:30 p.m., Monday through Friday. You can leave a message anytime, and your call will be answered as soon as possible.

Request a speaker from our orthopedics and sports medicine team.

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