Anterior Cruciate Ligament Reconstruction
- Nonsurgical Treatment of ACL Tears
- Surgical Reconstruction of the ACL
- Surgical Choices for ACL Reconstruction: Autograft vs. Allograft
- After Surgery
- Postoperative Risks
- Recovery Period
- Check List
- Useful Phone Numbers
The anterior cruciate ligament (ACL) is one of four ligaments in the knee. These ligaments work together to stabilize the knee during activities. Unfortunately, tears of the ACL are common and occur with twisting activities (such as playing basketball, tennis and soccer, or skiing) and direct blow injuries (such as those that occur in football).
An ACL tear usually occurs from a sudden event often accompanied by a "pop" sound. The knee will swell for a few hours and it may be uncomfortable to walk. The knee can also feel unstable. A physician can confirm the tear with a physical examination and a magnetic resonance image (MRI) scan. When the ACL is completely torn, it cannot repair itself and thus the ligament function is lost. After a few months, the ligament tissue will break down and be absorbed by the body.
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Nonsurgical Treatment of ACL Tears
A small percentage of people will do well after an isolated ACL tear without surgical reconstruction. These individuals tend to be older and less active. They are not involved with activities or sports that involve pivoting or "cutting." Knee braces can help prevent instability episodes by "hobbling" the knee and assisting with sensory feedback. However, most active people will continue to have instability even with the most expensive custom knee brace.
Before deciding to pursue nonsurgical treatment in a knee that is ACL deficient, it is important to make sure that there is no other damage to the meniscal cartilage pads or other ligaments. An MRI scan can determine with excellent accuracy whether additional damage is present. If there is significant damage to the menisci, surgery is usually recommended. If knee surgery is scheduled for other problems, then most people decide to reconstruct the ACL at the same time.
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Surgical Reconstruction of the ACL
Most people with a torn ACL will experience instability, a feeling that the knee gives way or feels loose. This instability commonly results in a reduction in activities, especially sports. More importantly, the instability will usually lead to additional damage to the knee.
Meniscal cartilage pad tears, articular surface cartilage injuries and additional ligament damage are common following untreated ACL tears. Some studies have shown that during the five years following an untreated ACL tear that 80 percent of individuals will have suffered additional damage because of instability. This damage often results in arthritis, a wearing out of the articular cartilage surfaces, which results in pain, stiffness and deformity. Most people with a torn ACL are unwilling to give up their activities and have a strong desire to prevent further damage to the knee. Therefore, most people elect to reconstruct the ACL.
The surgery to reconstruct the ACL involves taking a piece of tendonous tissue to replace the ACL. Tendons and ligaments share similar tissue composed primarily of collagen protein. The underlying concept behind the reconstructive surgery is that a tendon is surgically placed into the knee exactly into the position where the torn ACL was located. The tendon is fixed to the bone with biodegradable screws.
Approximately 95 percent of the time, the body will then reestablish the blood supply to the tendon and over the weeks following the surgery this blood supply will bring new fibroblast cells that will repopulate the tendon bringing it back to life. As a result, the "new living ACL" is seemingly just as good as the original and should last a lifetime. Follow-up studies, which show maintenance of stability and active lifestyles for many years after ACL reconstruction, support this theory.
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Surgical Choices for ACL Reconstruction: Autograft vs. Allograft
After deciding to undergo surgical reconstruction of the ACL, you must decide from where the reconstruction tissue will come. When the tissue comes from the same patient, it is called an autograft. When the tissue is taken from a different human donor, it is called an allograft. Tendons, such as the patellar tendon and hamstring tendon, can be used for autografts. The Achilles tendon, patellar tendon and hamstring tendon can be taken and used for allografts.
Autograft Reconstruction of the ACL
The first autograft reconstruction of the ACL was performed around 1918. The more common procedures, which are now performed with the use of arthroscope, became popular in the early 1970s. The most common autograft used is the central-third-patellar-tendon graft. This graft is actually comprised of a piece of the patella bone (kneecap), the central third of the patellar tendon and a piece of tibia bone (shinbone). The graft is usually 10 millimeters wide (3/8 inch) and 8 centimeters (4 inches) long. The patellar tendon defect created from taking this graft is usually closed with sutures and the donor site will heal during the months following surgery. The healing of the patellar tendon defect can lead to excessive scarring and sometimes pain.
Hamstring tendons from the back of the thigh can also be used to reconstruct the ACL. The most common hamstring tendon used is the semitendinosus. Often a second hamstring tendon, the gracilis, is also taken if the semitendinosus is not large enough. The donor hamstring muscles seem to tolerate the removal of their tendonous attachment but permanent hamstring weakness is expected following surgery.
The major disadvantage of autograft tendons is the additional damage to the knee from harvesting the tendon at the donor site. The donor site can become a source of pain, scarring and weakness. Excessive scarring can permanently reduce motion. The donor site can take longer to heal than the reconstructed ligament. Longer surgical times are needed with larger incisions. Early return to activities, while often safe for the reconstructed ACL, can cause injuries to the donor site.
The major advantage of using autograft tendons are that they have been used for the longest period of time and because they come from the injured person they do not have any chance of carrying organisms, which may cause infectious diseases.
Allograft Reconstruction of the ACL
The primary advantage of allograft tissue is that there is no additional damage to the knee and stronger grafts can be used.
The most common allografts use the patellar tendon and Achilles tendon. The Achilles tendon is the strongest and largest tendon in the body. Allograft tissues are taken from tissue donors through tissue banks. The donors are people usually under 40 years of age, often who have died from an accident. The donors are screened by tissue banks and are tested for infectious diseases. Screening histories, blood tests and cultures are obtained during tissue processing. These screening procedures must be clear of infectious disease or the tissues are rejected by the tissue bank.
The risk of disease transmission through allografts while never non-existent is extremely small. Allografts are poor vectors for disease transmission. The graft tissue has no living cells. It is frozen and kept in a deep freezer until used. The fact that the tissue has only a few cells and no living cells makes the donor graft tissue a poor transmitter of living bacteria or viruses that are responsible for transmitting most diseases. Because this tissue has no living cells, it is not necessary to match the donor and recipient, nor is it necessary to give anti-rejection drugs.
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You will be in the outpatient surgical facility approximately 90 minutes, but your surgery often only takes about 20 to 60 minutes. It is performed as an arthroscopically assisted procedure. Two to four skin incisions, or "portals," are placed in different areas in the front of the knee, dependent on tissue used. Through one of these portals the arthroscope - a small video camera the size of a pencil - is placed into the knee. With the magnification of the arthroscope, the physician can visualize any damage that has occurred. Through the other portals instruments are placed into the joint to remove, smooth or repair the tissues. All additional damage is corrected.
Water is infused through the arthroscope throughout the procedure and the tissues around the knee will absorb some of this water. The physician does not use a tourniquet device as here is no significant risk of bleeding. The ACL graft is placed into the knee through the small portals and placed into bone tunnels. The ACL graft will then be fixed with the latest biodegradable screws. These screws are MRI compatible and do not show up on X-rays. The small incisions are closed with absorbable sutures and skin tape so that there are no stitches to remove. An ice machine is often recommended after surgery. Most people go home a few hours after surgery. You will need to use crutches and a brace. At home a CPM (continuous passive motion) machine is used four to six hours a day to assist with motion.
After surgery, water mixed with small amounts of blood will often leak out of the portals and look like blood on the bandages. The drainage on the bandages is mostly water, which is normal.
Surgery is not without risks. Common risks include, but are not limited to, possible nerve injury, infection, bleeding, allergic reaction, and very rarely, death.
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After surgery you will be asked to stay in the outpatient surgical facility for a period of one to two hours to recover from any drugs you may have been given. You will also be allowed to sip some water and eat crackers. You will have a large bandage on your knee and a brace. You will need someone else to drive you home, as well as to be with you during the first 12 to 24 hours after the procedure.
It is important to do only what is necessary once you are home. You can use the restroom, get something to eat or answer the phone, but otherwise you should try to lie down with the leg elevated above the heart as much as possible. Take pain pills and anti-inflammatory medications immediately and regularly to help control pain. It is usually better to start taking the pain pills before the pain comes, so as not get "behind" the pain. Resume taking all medications, which you normally take.
Start the CPM machine once you get settled at home. The range of motion is preset at zero to 40 degrees. Please stay within this range. If you increase the motion too fast you may experience more pain the next day when the local anesthetic wears off. Also, if you chose to use the ice machine, continue for 24 to 48 hours.
First Postoperative Day
The day following surgery may be a lot tougher than the day of surgery. The numbing medicines used during surgery will wear off and there may be more pain. Try and use the CPM machine as much as possible while increasing the CPM range of motion as pain dictates. Ice bags or the ice machine should be used continuously. The leg should be elevated as much as possible above the heart. Try to do as little activity as possible and take your pain medication regularly. Do not get behind your pain, or it may get quite severe.
Remember, it is normal for bloody drainage to appear on the outer bandages. The drainage is mostly absorbed water mixed with small amounts of blood. The bandage should be shifted slightly so that dry bandage covers the draining portal. You can also place new bandages around the knee.
Please make sure you have a postoperative appointment scheduled prior to your surgery, if not call the Sunnyvale office at (408) 732-0600 to make your follow-up appointment for one to four days after surgery. We will discuss your surgery and check your wounds at this appointment. You will start physical therapy after this first appointment. Please bring your operative pictures and diagrams that were given to you in the hospital so that we may discuss them.
Nausea and Pain Medication
Remember that surgery is not painless. Try to take your pain pills as directed even before you experience pain. Nausea and vomiting are very common postoperative problems. If you start to get nauseated, try and minimize the use of the codeine pain medication (hydrocodone or vicodin) and use Tylenol and Motrin for pain control. (Codeine products can make you nauseated.) Start eating more slowly beginning with soup and crackers. If you're prone to nausea, ask for anti-nausea medication prior to surgery.
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Potential Risks with ACL Reconstruction
- Wound Infection
Signs of infection include redness around the incision area, discharge of pus from the wound, increased pain and a fever of more than 101 degrees with chills and/or sweating. If you are concerned, call the office at (408) 732-0600.
- Blood Clots
Blood clots (thrombophlibitis) can occur after arthroscopic knee surgery. Usually, but not always, they occur in individuals with risks such as people who are more than 50 years of age, smoke or are overweight. Signs of blood clots include increased calf pain and the inability to put weight on the leg due to pain, as well redness and swelling of the calf.
- Urgent Signs
If you experience pain in your back or shortness of breathe, call 911 immediately. If you are concerned but do not feel it is an emergency, please call the office at (408) 732-0600.
- Risk of Graft Failure
The signs of a graft not forming a blood supply and weakening are not obvious. However, they are usually discovered during the postoperative evaluations.
- Loss of Motion
After surgery, it is very important to obtain and maintain full extension (getting the leg as straight as the nonsurgical leg).
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The weeks following ACL reconstruction surgery will be somewhat difficult but also rewarding. It is important to follow these instructions. In general, listen to your body. Your first goal is to regain full extension (straightening the knee) and prevent postoperative complications such as infection, blood clots and stiffness.
You can begin putting weight on the leg while it is in the brace and using crutches until you are stable walking without them. Generally, it is best to stop using the crutches first and walk with your leg in the brace. The brace can be removed when you know you will not slip or fall. Usually, the only way to hurt an ACL graft is to slip suddenly or fall.
Most patients go to physical therapy three times per week, but exercises should be performed daily. The more you work without increasing your pain or swelling, the faster you will recover. Some patients are off their crutches in a few days and out of the brace within a week, biking in 10 days and able to jog in six weeks. In most cases, you will be able to return to all sports without a brace.
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- ___ I know where to go.
- ___ I know when to go.
- ___ I have checked with my insurance company.
- ___ I confirmed the time of my surgery by calling the surgery center.
- ___ I gave the surgery center a phone number where I can be reached on the day of the surgery.
- ___ I stopped drinking liquids and eating food at midnight prior to surgery.
- ___ I am wearing loose clothing.
- ___ I am totally relaxed about surgery, and I am excited about the prospect of getting better.
- ___ I will make a postoperative appointment with my physician one to four days after surgery, if I have not already.
- ___ I am still excited about getting better, and I am relieved that the surgery is over.
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Useful Phone Numbers
Fremont Surgery Center
Ramon Santo, Surgical Coordinator
Palo Alto Clinic (Tuesday and Thursday)
Sunnyvale Office (Monday and Wednesday)
Palo Alto Center
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