Anterior Cruciate Ligament Tears

What is the Anterior Cruciate Ligament (ACL)?

The ACL is one of four major ligaments inside the knee that is responsible for maintaining stability of the knee during certain activities.  The Anterior Cruciate Ligament functions to maintain stability in activities such as turning, pivoting and twisting.  Most people do not require an ACL for unidirectional (straight ahead) activities such as walking or even jogging on a track or road.  ACL tears are the most common form of knee ligament tears.  ACL Injuries are also one of the most common ligament injuries in the human body.   The incidence of knee ligament tears and ACL Injuries is increasing over the years due to many factors.  Some research shows that young women are more prone to ACL tears than their male counterparts.  This may be due to our anatomical differences and some studies show that ACL tears are more common during certain times of a woman’s menstrual cycle.

How do ACL injuries occur?

There are many ways to tear your anterior cruciate ligament.  Although some injuries to the ACL occur as a result of being struck on the side of the knee, most anterior cruciate ligament injuries are non-contact in nature.  Most ACL tears or injuries occur during a rapid pivot to stop and change direction.  Usually the athlete was accelerating or decelerating rapidly; turning, pivoting or twisting.  When the ACL tears, the knee  buckles or gives out and frequently a pop is felt or heard and swelling occurs.  When the ACL is torn it is typically followed by swelling of the knee.   If you sustained a knee injury while pivoting, turning or twisting rapidly, heard a pop and experienced swelling,  there is a very strong chance that you tore your anterior cruciate ligament.  The knee might not swell immediately after an anterior cruciate ligament tear, the knee might swell after an hour or two — so get that ice on your knee as soon as possible.  Ice should be applied 15 minutes on and 10 minutes off to minimize risk of frostbite, and you should have a towel or something else between a bag full of ice and your skin.

This is a video of an young man suffering an ACL tear.  Notice how the knee gives way after he pivots and turns.

 

What is the immediate treatment for an ACL injury?

If you suspect you have suffered a ligament tear in your knee, or more specifically, an ACL tear , you should immediately put ice on your knee, apply compression via an ACE wrap (not too tight) and obtain a pair of crutches… you may need to see your orthopedist or visit an Emergency Room for these.  The ice should be used 15 min on and 10 min off and you can continue this for the first two to three days to minimize swelling.  Immobilization or bracing of the knee after an anterior cruciate ligament tear is typically not necessary and moving the knee helps prevent stiffness and atrophy.  Crutches are used after an Anterior Cruciate Ligament Tear to be sure that you do not suffer an instability episode where the knee gives out and you fall down.   Your Orthopedic Surgeon will let you know when you can walk without crutches.

You should have the knee examined and have X-rays taken within the first few days following a severe knee injury to confirm the presence of an anterior cruciate ligament tear.  Usually a physical examination alone will confirm the presence of an ACL tear.   An MRI is useful to confirm the presence of a ligament tear and it will also show if you tore your meniscus, or damaged your articular cartilage as well.  It is important for you to work on limiting swelling (ice, compression and anti-inflammatories), and it is important to work on range of motion.  The faster you gain back painless motion, the less atrophy and weakness you will have after a severe knee injury or an ACL tear .  Physical therapy can be useful after your initial ACL injury to assist in achieving these goals.

Is surgery always necessary for ACL injuries?

Adult Anterior Cruciate Ligament Tears:

First and foremost… bear in mind— The indication for an ACL reconstruction is not simply the fact that you have an ACL tear! Please read that again!  :-) Many adults simply think (or are told by friends or even surgeons) that since the anterior cruciate  ligament is torn, they need the ACL repaired–this is simply not true, and this is not what the scientific literature on ACL tears reveals. Overall, in adults, the indication for an ACL reconstruction is symptomatic instability (the knee gives way or buckles) after your recovery from the initial injury and you complete your physical therapy program for an anterior cruciate ligament tear.  If you complete your rehabilitation program and your knee is stable for your chosen activities of daily living and you do not work on roofs, ladders, or are a rock-climber, etc — then non surgical management of your anterior cruciate ligament tear is possible — and effective.

ACL tears in children or pediatric ruptures of the ACL are looked at differently.  We’ll discuss this in a second.

Anterior cruciate ligament surgery to reconstruct a torn ACL is not emergency surgery — and if ACL surgery is necessary, it should probably be postponed until the knee swelling has diminished and you have restored range of motion and strength to the knee.  The stronger and more flexible your knee is going into ACL surgery, the easier your recovery from an ACL reconstruction should be.

In adults, an ACL is occasionally (but not always) necessary to compete in certain sports with cutting pivoting or twisting. Many adults with  ACL tears do very well without surgery.   Many adults return to playing tennis, or even *gentle* skiing, etc without needing ACL surgery.

Surgery to reconstruct your ACL is necessary if you have instability which significantly affects your quality of life; and physical therapy and perhaps bracing do not improve your ability to return to your chosen activity and thus improve  your quality of life.   You always have the option to alter your lifestyle to suit your knee or alter your knee to suit your lifestyle. IF the PT fails to control your anterior cruciate ligament  instability—and if your knee remains unstable following an ACL injury and you do not wish to wear a brace, or do not wish to alter your lifestyle,  then an ACL reconstruction is the preferred method of managing complete ACL tears in symptomatic individuals.

Unfortunately, once you have torn your anterior cruciate ligament you run the risk of developing osteo-arthritis…. regardless of whether or not you have it repaired.  Surgery will not prevent arthritis from occurring.

Evidence Based Medicine (EBM) : Here is a Podcast from the authors of a recent study. Their conclusion : Whether or not you were treated with early PT and early ACL reconstruction — or you waited and decided whether or not surgery was the right option for you — had no measurable effect on your results and ability to return to activities.

Pediatric Anterior Cruciate Ligament Tears:

Unfortunately, surgery is usually *necessary* for most pediatric  ACL tears.  Recent studies (2010) have shown that an *early* ACL reconstruction can minimize the risk of your child developing “secondary” injuries such as meniscus tears. Unlike adults, most children simply do not, can not, or will not alter their activity patterns.  Therefore they have been found to be at much higher risk of developing secondary injury patterns when their knee buckles or gives way repetitively after they have suffered an anterior cruciate ligament tear or injury.  Certain secondary injuries (meniscus tear) raise the risk of developing arthritis at a relatively young age. Please note,  arthritis can still occur following non-surgical management or surgical management of an ACL tear… but the risk of arthritis  ( and rate of progression) increases if your child goes on to further damage other structures within the knee.

 

How is an ACL tear treated at time of surgery?

Anterior Cruciate Ligament Surgery involves the reconstruction of the native ACL ligament.  The ACL cannot be repaired in a traditional sense.  That means we can not sew together the torn ends of the ACL —instead we need to replace it (with a graft).  This is called an Anterior Cruciate Ligament Reconstruction.

Reconstructive  ACL surgical techniques have undergone significant modifications over the past few years.  Many sports medicine physicians, especially academic sports medicine physicians, have started performing “Anatomic” ACL reconstructions.  That means that the new anterior cruciate ligament graft, or new ACL is placed exactly where your old ACL was.  This makes perfect sense, no? But, this wasn’t (and still isn’t) the way most ACL reconstructions were/are performed.  IF you are contemplating an ACL Reconstruction, be sure your surgeon will be performing an “anatomic reconstruction”.

During surgery we drill tunnels which enter and leave the knee joint where the ACL used to be. We then pass the “graft” through the tunnels and lock the graft in place — under tension.  There has been a lot of research lately into the importance of obtaining an anatomical reconstruction of the ACL.  Many many surgeons still place the graft in an *improper* position.  This was the teaching decades ago and it did NOT reproduce the normal anatomy of the knee.  The academic sports medicine community has been at the forefront of offering their patients anatomic ACL reconstructions which restore the normal ACL ligament location. During anterior cruciate ligament surgery, this is very important in order to restore proper mechanics and to restore stability.

 

Which ACL graft should I choose?

The choices for which tissue to use as a graft comes down to two basic choices, allograft or autograft.  An allograft is taken from a cadaver and autograft is your own tissue.  If choosing your own tissue for an ACL reconstruction we have the hamstring tendons or the patella tendon as a choice for grafts and with allografts we have a multitude of choices available.  Autograft is typically favored over allograft.  Allografts carry a very small  risk of disease transmission… and to minimize that risk, many companies will radiate grafts — which could weaken them in the long run.  For a primary ACL reconstruction autograft is probably your best choice.

Still confused…  Watch this video on the personality of an injury.  It explains how the same injury (an Anterior Cruciate Ligament Tear) may not behave the same way in all individuals.

 

What is a Double Bundle Reconstruction?

A normal “native” ACL has two bundles that it is composed of.  An anteromedial and a posterolateral bundle.  99.9% of reconstructions performed today only recreate the AM bundle.   Dr. Freddie Fu, 5 or so years ago proposed that we should be reconstructing both bundles to better control rotational instability that some patients continue to complain of after a routine ACL reconstruction.

A double bundle recon involves four tunnels and two separate grafts…usually hamstring grafts to recreate both AM and the PL bundles.

I have been very happy with the results of my DB-ACL reconstructions, as have others, but is it going to take a head to head large multi-center study to determine which one is actually better.    That way we can provide an answer that is evidence based and supported by the literature.

I stumbled upon a very interesting site …. ACL Surgery .  This site is put together by a patient who underwent the procedure and found that the information available to them was incomplete.  I do not condone nor advise that you take anecdotal notations as medical advice and in no way do I offer this as medical advice.  But if you are seeking to learn what an ACL reconstruction is like from the patient’s perspective, I think you may find this site useful.

What is the best treatment for your ACL condition?

If you live in Dutchess or Westchester County, NY … Feel free to call 914-789-2735 to review your options.   

You can book your appointment online! 

 

Know your options. Contact me if you have any questions about ACL injuries.

 

Contact Howard Luks, MD

 

 

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