If you have a torn ACL (anterior crucial ligament) in your knee, you may need to have reconstructive surgery.
The ACL is a tough band of tissue joining the thigh bone to the shin bone at the knee joint.
It runs diagonally through the inside of the knee and gives the knee joint stability. It also helps to control the back-and-forth movement of the lower leg.
What is the ACL?
The ACL runs from the back of the thigh bone to the front of the shin bone and passes through a special notch within the femur. The ACL controls how far the shin bone moves beneath the thigh bone. If the shin bone moves too far, the ACL may tear or rupture due to the strain. When the knee is extended, the ACL is the first ligament that tightens and reduces further motion.
How does a torn ACL happen?
Knee injuries can occur during sports such as skiing, tennis, squash, football and rugby. ACL injuries are one of the most common types of knee injuries, accounting for around 40% of all sports injuries.
You can tear your ACL if your lower leg extends forwards too much. It can also be torn if your knee and lower leg are twisted.
Common causes of an ACL injury include:
– landing incorrectly from a jump
– stopping suddenly
– changing direction suddenly
– having a collision, such as during a football tackle
If the ACL is torn, your knee may become very unstable and lose its full range of movement.
This can make it difficult to perform certain movements, such as turning on the spot. Some sports may be impossible to play.
What are the symptoms of a torn ACL?
The most common torn ACL symptom is a popping sensation or sound followed by leg weakness. The knee may become inflamed or swell after suffering an ACL tear. A feeling of the knee slipping backward may also be present after an injury to the ACL. The swelling and discomfort from an ACL tear usually subsides within 2-4 weeks from the initial injury. Despite the reduction in pain or swelling, you still may experience knee weakness or instability. If left untreated, an unstable knee may be more likely to develop arthritis.
What torn ACL surgeries are available?
Arthroscopic ACL Surgery
The majority of ACL surgeries involve replacing a torn ACL with a graft from another ligament or tendon. This type of ACL surgery is often performed with an arthroscope, which is a small tube with a camera on the end. The internal images of your knee seen through an arthroscope will be displayed on a monitor in the room, offering a live view of your knee. This type of ACL surgery does not require the actual knee joint to be surgically opened. The arthroscope is used to locate the damaged ACL, which will then be repaired. Arthroscopic ACL surgery is less invasive than open knee surgery, so the majority of patients are able to return home the same day as their surgery.
ACL Surgery with Hamstring Graft
A graft from the hamstring may be used to replace the damaged ACL. Hamstring grafts are generally favored because the hamstrings do regenerate with time. Once the damaged ACL is removed, the hamstring graft will be prepared and placed through the tunnel in the femur. The bottom of the graft will be anchored with a bio-absorbable screw, which will slowly be incorporated into the bone with time.
Patellar Graft for ACL
Similar to a hamstring graft, a patellar graft can also be used during ACL surgery. A small tunnel will be made in the upper tibia, which will create an opening where the ACL would attach to the tibia. Another tunnel will be made through the femur where the ACL would attach.
Allograft ACL Reconstruction
During ACL reconstruction, an allograft may be used to replace a damaged tendon. An allograft is tissue that is harvested from another individual. This allograft material may be harvested from the tendon of the tibia, patella, hamstring, or Achilles.
Deciding to have surgery
The decision to have knee surgery will depend on the extent of damage to your ACL and whether it’s affecting your quality of life.
If your knee does not feel unstable and you do not have an active lifestyle, you may decide not to have torn ACL surgery. It’s important to be aware that delaying surgery could cause further damage to your knee.
Risks of ACL surgery
ACL surgery fully restores the functioning of the knee in more than 80% of cases, but your knee may not be exactly like it was before the injury, and you may still have some pain and swelling.
This may be because of other injuries to the knee, such as tears or injuries to the cartilage, which happened at the same time as or after the ACL injury.
As with all types of surgery, there are some small risks associated with knee surgery, including infection, a blood clot, knee pain, and knee weakness and stiffness.
Recovering from surgery
Recovering from a torn ACL surgery usually takes around 6 months, but it could be up to a year before you’re able to return to full training for your sport. It is incredibly important to keep up with your physical therapy, and to not over-exert yourself while healing.