The anterior cruciate ligament (ACL) is one of four bands of tissue that provide stability to the knee. Specifically, the ACL prevents the shinbone (tibia) from sliding in front of the thighbone (femur) and keeps the knee from rotating. When this critical ligament tears, surgery is often needed—especially when the tear is complete.
The orthopedic surgeons at NewYork-Presbyterian Columbia Orthopedics are highly skilled in ACL reconstruction for people of all ages and abilities. We use the latest approaches in minimally invasive surgery to rebuild the ACL so you can get back to normal life quickly.
What is ACL Reconstruction Surgery?
ACL tears may be partial or complete, meaning the ligament is split into two pieces. They often happen in sports—especially basketball, volleyball, soccer, and football—when an athlete stops or pivots suddenly, lands from a jump incorrectly, or collides with another player. The person may hear a popping sound when the ligament tears and experience pain, swelling, and reduced range of motion. ACL reconstruction surgery involves replacing the torn section of the ligament with a "graft"—a band of tissue that serves as a scaffolding for the new ligament to grow on and helps stabilize the knee.
ACL repair vs. reconstruction
One approach to treatment is to repair the ACL tear by stitching the torn ends of the ACL back together. However, this is not an option for most people; ACL reconstruction is more effective for restoring joint stability while the body heals and the new ligament grows back.
Types of ACL Reconstruction & Repair
There are a few ways to treat ACL tears through reconstruction or repair:
- Autograft – This reconstruction surgery involves replacing the torn ligament with a piece of tendon (the tissue that connects muscles with bones) from the patient's kneecap (patellar tendon), hamstring, or thigh (quadriceps tendon)
- Allograft –The graft used is a piece of tendon from a tissue bank (from a person who died and donated their body to science). This is most often used in older individuals but less so in younger adults, due to a higher risk of having a repeated tear.
- Synthetic graft – The newest type of graft, used for ACL repair, is the artificial Bridge-Enhanced ACL Repair (BEAR) Implant, which was just approved by the U.S. Food and Drug Administration in December 2020. It is made from bovine collagen (cow protein). Synthetic grafting is an option for patients age 14 and over who have finished growing and have a portion of the ACL still attached to the thighbone to complete the reconstruction.
How Is ACL Reconstruction Performed?
ACL reconstruction is a minimally invasive surgical procedure performed using arthroscopy. You will receive anesthesia so you are comfortable during the procedure, which typically takes about two hours. During the operation, the surgeon inserts a tiny camera into your knee through a small incision. The camera transmits images from inside of your knee that your surgeon can see on a video monitor in the operating room. The surgeon then makes several other small incisions to insert other instruments.
- First, the torn ACL is removed
- If you are having an autograft, the surgeon will remove the tendon tissue needed from another part of your body to create the graft
- The surgeon will make tunnels in your bone to bring the graft tissue through, which will be in the same place as your old ACL
- The new ligament is attached to the bone with screws or other devices to secure it in place. As healing progresses, the bone tunnels fill in, holding the new ligament in place.
- If you are having a synthetic graft, it is stitched into place to bridge the gap between the torn ends of an injured ACL. Your own blood is injected into the implant during the surgery to form a clot that enables the body to heal. Your body absorbs the implant and replaces it with your own tissue within eight weeks.
- Your incisions will be closed, stitched, and covered with a dressing
Risks to Consider
Like any surgery, ACL reconstruction has certain risks, which may include:
- Stiffness in the knee
- Kneecap pain
- Reaction to the anesthesia
- Failure of the ligament to heal
- Blood clot (rare)
Your surgeon will talk with you about potential risks before your procedure.
Preparing for Surgery
Your care team will help you prepare and learn all you need to know before undergoing ACL surgery.
- Your doctor will ask you to stop taking medications that may interfere with blood clotting—such as blood thinners, aspirin, ibuprofen, and naproxen—within two weeks of the operation
- If you have heart disease, diabetes, or other medical conditions, you may need an exam and preoperative testing by your primary care physician to make sure it is safe for you to have the surgery
- Prepare your home to make it easier and safe to get around on crutches after the operation. Reduce clutter. Remove area and throw rugs, which can slide underfoot and result in a fall.
- Have a friend, family member, or health aid escort you home from the hospital and help you around the house in the days after surgery
- Fill your pain medicine prescription ahead of time so you have it when you get home
- You may be advised not to eat or drink anything for up to 12 hours before the procedure
ACL Recovery Timeline
Your doctor will prepare you for what to expect when recovering from ACL surgery.
- Most people can move their knee right after surgery, which may help prevent stiffness
- You’ll likely be able to go home the same day and may need to take medicine for your pain
- Some patients need to wear a knee brace for the first six weeks and also use crutches during this time
- Physical therapy is important to help you regain motion and strength in your knee. Therapy can last up to four to six months.
- If you adhere to your physical therapy schedule, you should be able to regain full use of your knee in six to nine months
What not to do after ACL surgery
You should not expect to return to your usual level of activity right away after ACL surgery, especially if you play sports that involve quick changes in direction. Your body needs time to heal fully; otherwise, you run the risk of re-injuring your knee. Following the instructions from your care team is important for your recovery.
- Take care of your incisions as directed
- Aim to attend all physical therapy sessions, and be sure to do the exercises your therapist tells you to do at home
- Go for follow-up visits with your doctor as recommended
ACL reconstruction generally takes about two hours.
Sleeping on your back or side with your knee kept straight is best. Ask your surgeon or physical therapist if you should sleep with or without your brace.
You should rely on crutches until you can walk without a limp, which usually takes one month. Each person's recovery is different, though, so speak with your surgeon at your follow-up visits about the best time for you to resume walking.
You should not drive while you are taking prescription pain medication. After that, you may drive if your left ACL was reconstructed. You should wait four to six weeks before driving if your surgery was on the right side.
There is some pain after ACL surgery, but it varies from person to person. Some people need prescription pain medication for two to three weeks, while others may be able to able to get by with over-the-counter pain relievers. You should try to decrease your use of prescription pain medicine as time passes.
Receive ACL Reconstruction at NewYork-Presbyterian
If you sustained a knee injury and you have pain and swelling, see a doctor to learn if you have a torn ACL or other knee injury that requires medical attention. Some people with ACL injuries may be treated with a brace and physical therapy.
The Columbia orthopedic surgeons at NewYork-Presbyterian can determine the best treatment for you and let you know if surgery is recommended. Our doctors are highly experienced in ACL repairs and reconstruction and have refined new approaches to improve patient outcomes. They work closely with rehabilitation medicine specialists to ensure you have the best chance of making a complete recovery.
Make an appointment with an orthopedic expert today.