There are more than 200,000 ACL injuries each year in the United States alone, and approximately 65% of these injuries are treated with reconstructive surgery. ACL graft options and selection is one of the main topics of discussion between orthopedic surgeons and their patients. Numerous factors including patient age, occupation, and activity level, graft availability, surgical history, existing tendinopathy, and the experience and preference of the surgeon, should be considered prior to determining which type of graft will be used for reconstruction. We’ve teamed up with Dr. Nima Mehran, an orthopedic surgeon who specializes in sports medicine, to cover everything you need to know about what you can do prior to surgery for maximal results, graft selection, and what to expect immediately after surgery. With this guide, you will no longer have to fear the unknown!
Prehab Will Improve Surgical Outcome – Regardless of ACL Graft Option
The rationale for prehab prior to ACL reconstruction is simple: to maximize the function and health of the knee prior to surgery. The stronger your knee going into surgery, the stronger it will be when you come out. The goals of prehab are to:
- Control joint swelling and edema
- Regain normal knee range of motion (ROM)
- Regain a normal gait (walking) pattern
- Improve lower extremity strength and coordination
It has been demonstrated that patients who exhibit full knee extension ROM, absent or minimal swelling, and no knee extension lag during a straight leg raise before surgery have better surgical outcomes. The single most important variable to work on in prehab is SYMMETRICAL knee extension range of motion.
Pre-operative range of motion is indicative of post-op range of motion, so restoring full symmetrical knee extension is vital if you hope to achieve full range of motion after surgery!
To control swelling and pain, elevate the leg and use icepacks around the knee. Try to straighten your leg as much as possible when icing and keep icing sessions no longer than 15 minutes.
It’s extremely common to have limited ROM due to swelling and pain following surgery, and regaining full knee ROM (especially extension) can sometimes be extremely difficult. Therefore, regaining as much range of motion as possible prior to surgery is of paramount importance. Some exercises you can do to improve range of motion include:
- Heel slides
- Ankle Pumps
- Bag hangs
- Hamstring stretch
- Calf stretch
- Quad stretch
Preoperative quadriceps strength is a significant predictor of knee function after ACL reconstruction, so it is extremely important to regain as much quadriceps strength as possible prior to surgery. Also, strength and control of the gluteal muscles play a huge role in preventing a future non-contact ACL injury (READ: The Gluteus Maximus and it’s Unusual Role in Medial Knee Collapse), so strengthening the hip musculature should be implemented as well. Some exercises you can do include:
- Knee extension full ROM
- Hip abduction
- Hip extension in prone/fire hydrant
- Hamstring curl
- Toe raises
- Side steps
- Box squats
In a recent study by Shaarani et al 2013, they examined the effect of a 6-week prehab protocol that included strengthening exercises (with a focus on the quadriceps) to a group that did nothing before surgery. The prehab group reported improved knee function subjectively, as well as scoring better on the single leg hop tests at 12 weeks post-op. Putting in a little bit of time and energy into prehab has the potential to drastically improve your rehabilitation outcome in those ever so important first couple months of intensive rehabilitation.
Things to Know About Your Rehabilitation Protocol
First and foremost, make sure you have a physio on your side managing your rehab! (If you live in the US, you can use this database to find a local provider near you). Ideally, you visited your physio prior to surgery to come up with an individualized rehab plan specific to YOUR knee. You and your physio will be embarking on a 9+ month (yes, a minimum of 9 months) of intensive rehabilitation, strength and conditioning, and return to sport training to not just get you back on the field, but back out there even stronger than you were prior to injury. (READ: How Do I Know When I Am Ready to Return To Sport Following an ACL Reconstruction?)
In general, ACL rehabilitation protocols are criterion-based. This means that in order to move onto the next phase of rehab, you must meet certain criteria like regaining full knee extension or regaining at least 60% of your quadriceps strength in comparison to the other side. Phases allow you and your physio to set objective goals that maximize your ability to exercise at your current level of function while minimizing the risk of injury to the healing tissue.
Remember, everyone’s rehab process is completely different! Just because you haven’t gained back full ROM as fast as your buddy, it does not mean you’re behind! Your physio and orthopedic surgeon design your rehabilitation protocol for YOUR knee. They know the quality of your tissues, what other structures were injured (i.e. mensici, medial collateral ligament, etc.), and what other structures (if any) may have been repaired in addition to your ACL. All of these factors will play a role in designing your comprehensive rehabilitation plan. Remember, guidelines you read online (including ours!) are merely a general structure to follow for an isolated ACL reconstruction and the timeline is not a hard and fast rule! (READ: MCL Rehabilitation Options)
ACL Graft Options and Selection with Dr. Nima Mehran
An anterior cruciate ligament (ACL) tear is a devastating injury for any athlete. Athletes who wish to continue playing sports that involve cutting and pivoting such as basketball, soccer, or football will likely need surgery to continue playing. Once an athlete has decided to proceed with an ACL reconstruction, a great deal of time is spent discussing ACL graft options. Many factors such as age, activity level, and sport play a role in determining the most optimal graft choice for an athlete.
THIS VIDEO IS A MUST WATCH!!!
You may be wondering “what exactly is a graft?” A graft is the tissue that is used to create a new ACL. The first decision is determining if you should use your own tissue (autograft) or tissue from a donor (allograft). The benefits of using your own tissue include decreased risk of disease transmission and decreased time to completely morph into a mature ACL when compared to a donor tissue. However, using your own tissue means that it has to be surgically removed from another part of your body which results in more pain after surgery. The benefit of using a donor tissue is that you will not have extra pain from a donor site, but the downside is that the graft takes longer to become your new ACL and there is an extremely small risk of disease transmission.
Autograft of Allograft?
So how do you pick? Evidence has given us some great general guidelines, but the most important thing is to be honest with yourself and your doctor about your activity level and goals for the future. Based on large high-level national studies we have seen that younger age and higher activity level are the biggest risk factors for re-injury after ACL reconstruction. Many studies show that patients in their early twenties or younger have a much higher risk of tearing the newly reconstructed graft if they have a donor graft placed compared to using their own tissue for a graft. On the other hand, there is good evidence to support that there is a similar risk of tearing a newly reconstructed ACL whether an allograft or autograft is used in athletes over the age of 40. In high level athletes or in active patients under 30 who would like to continue playing cutting sports and have no limitations, I highly recommend using an autograft. However, if a patient is closer to 40 and older, or is a very not very active, I recommend using a donor tissue. The tricky part is when the patient is a 25 year old who wants to have their ACL reconstructed but they lead a very low demand lifestyle (plays minimal to no cutting sports). Similarly, it can be a though call if a patient is a 45-year-old super high level athlete. That is why it is important for your doctor to really know you as a patient and understand your current and future goals so they can help you make the best decision for you, your knee, and your needs.
ACL Autograft Options – Hamstring, Patellar, and Quadriceps Tendon
So if the best choice for you is your own tissue (autograft), where would your doctor take the tissue from? This is the next big part of the discussion and is once again where your age, size, and activity level can play a role. The two most common graft choices, both nationally and internationally, are hamstring tendon and patellar tendon. However, in recent years quad tendon has been becoming more popular. All three are good graft choices with successful results, but I would like to give you some details about the pros and cons of each graft choice to help make the choice easier based on your personal preferences.
I would like to compare the two most commonly used autografts in both the US and Europe, patellar tendon and hamstring tendon. Currently, the most common graft choice being used in the United States in professional basketball and football players is the central third of the patellar tendon (which includes bone from your knee cap and from your shin bone on either end). The advantages of patellar tendon include that bone heals into the bone tunnels that are created for the new ligament. Bone to bone healing has been shown to be more reliable and stronger than soft tissue to bone healing. Despite its pros, patellar tendon also has cons. The most common complaint is pain in the front of the knee from where the graft was taken. This knee pain is usually felt with kneeling in the first two years after surgery and generally improves. Also, there is a very small chance that the knee cap can break since bone is being removed from it for the graft. The hamstring graft can be a better option with good results for those athletes who must kneel a great deal since it has a lower likelihood of pain in the front of the knee with kneeling. Additionally, the hamstring graft makes for a slightly easier surgery on the surgeon, as well as a slightly smaller incision for those who are concerned with cosmetics. However, some patients experience a slight loss of hamstring strength which can be a problem for certain athletes. Additionally, and most importantly to some patients, recent literature has shown that when compared to the patellar tendon, hamstring autograft patients have a slightly higher risk of their graft tearing in the first few years after surgery.
The final autograft option is quad tendon. The quadriceps tendon is taken above the knee cap and can either be taken with a portion of bone (from the kneecap) on one side, or with no bone at all. There is a great deal of excitement about this graft, however, there are few long term studies at this point which is why I am not comparing it directly to the other two autograft types. In short and intermediate term studies it has been shown to be a great option. Its major advantages are the thickness of the graft and that it causes minimal anterior knee pain. Its largest disadvantage at this stage is that we do not have the sample size or years of results like the other two grafts; so only time will tell.
Regardless of which graft you feel fits you best, it is important to discuss all options with your surgeon and make sure it is a graft he or she has a great deal of experience using. I wish you the best on your road to recovery and know that there are a lot of great resources (physiotherapist, trainers, physicians and other patients) that you can always speak with.
After surgery, you will most likely be given crutches and a knee brace. Your orthopedic surgeon will determine how and when to use the crutches and brace. For an isolated ACL reconstruction, you can put some weight on your knee immediately. However, if other structures such as a meniscus is repaired, weight bearing is typically limited unless you’re braced in full extension. Remember to ask your surgeon how much weight you are allowed to put on your knee! Most surgeons will advise keeping your brace locked into an extension position while walking (and sometimes even sleeping). Your physio will determine when you’re strong enough to unlock the brace to 90 degrees. The brace is important because it protects your knee from buckling and giving way during the post-op period when your quadriceps muscle isn’t firing as optimally as it could be. Remember, it is better to be overly cautious than risk having another ACL surgery!
We wish you the best of luck with your ACL rehabilitation! Don’t think of this time as missing a season. Rather, see it as preparing to become the next Adrian Peterson in your respective competitive league. A proper rehabilitation program is so much more than just rehab, its [P]Rehab to PREVENT a future injury down the road!
About the Co-Author: Dr. Nima Mehran
Nima Mehran, M.D., is an orthopaedic surgeon specializing in sports medicine and joint replacements. He earned his undergraduate degree at the University of Southern California, attended the Chicago Medical School and was Chief Resident during his orthopaedic surgery residency at Henry Ford Hospital. Dr. Mehran has published several scientific papers and has delivered numerous scientific lectures. He has been on the physician team for the USC Trojan Football team, Los Angeles Lakers, Los Angeles Sparks, Los Angeles Dodgers, Los Angeles Kings, and Anaheim Ducks.
Adams, Douglas, David Logerstedt, Airelle Hunter-Giordano, Michael J. Axe, and Lynn Snyder-Mackler. “Current Concepts for Anterior Cruciate Ligament Reconstruction: A Criterion-Based Rehabilitation Progression.” Journal of Orthopaedic & Sports Physical Therapy 42.7 (2012): 601-14. Web.
Mehran, Nima, Bill Moutzouros, and Asheesh Bedi. “A Review of Current Graft Options for Anterior Cruciate Ligament Reconstruction.” Journal of Bone and Joint Review3.11 (2015): n. pag. Web.
Shaarani, Shahril. “The Effect of Prehabilitation on the Outcome of Anterior Cruciate Ligament Reconstruction.” American Journal of Sports Medicine 41.9 (2012): 2117-127. Web.