A guide "by skiers, for skiers" to anterior cruciate ligament injury: diagnosis, conservative rehab vs. surgery, graft choices, the surgical experience, rehab and more. While this is not a medical resource and should not substitute for a proper evaluation and course of treatment prescribed by a medical professional, the intention is to gather together both authoritative information and anecdotal evidence to help skiers understand what they may experience and the choices that have to be made in the aftermath of an ACL injury. Sources will be clearly identified throughout.
Table of Contents
- Anterior Cruciate Ligament Basics
- Injury and Diagnosis
- Do I Need Surgery?
- ACL Reconstruction
- Rehab and Recovery
- Return to Play
The anatomy of the knee:
The ACL is one of the two cruciate ligaments that run through the centre of the knee. Together with the other ligaments it acts as a stabilizer for the knee, preventing the tibia (shinbone) from moving too far forward in relation to the femur (thighbone) when the knee is placed under increased forward stress.
ACL tears are a common athletic injury, usually resulting from excessive pressure being placed on the ligament by a blow or twisting force. Tears fall into three categories:
- Grade 1 (mild) - a sprain with minimal damage to the ligament fibers and no noticeable laxity in the joint afterwards
- Grade 2 (moderate) - an incomplete tear with some laxity in the joint
- Grade 3 (severe) - a complete tear with significant laxity, often leading to an unstable or buckling knee
The ACL has no blood supply, so once it is torn it cannot repair itself.
(More information at: http://www.netwellness.org/question.cfm/13193.htm)
Skiers and ACL Injury
ACL injuries are unfortunately common among skiers, accounting for approximately 10-15% of all skiing injuries. Damage to the ACL while skiing is characterized by a ski that fails to release following a fall, and catches in such a way that significant twisting pressure is applied to the joint. Mechanism of injuring the ACL are:
Hyperextension of the knee - If the knee is straightened too far beyond its normally straightened position, this is a common cause of an ACL tear.
Pivoting of the knee - Excessive inward turning of the lower leg.
Combination of these two motions.
The following scenarios are common causes of ACL damage while skiing:
- Falling over backwards with weight over the downhill ski
- Attempting to recover from a fall or off-balance position while still moving
- Landing a jump with weight on the tails
- A blow to the lower leg from another skier or boarder
It's very common for damage to occur other structures in the knee, especially the medial collateral ligament (MCL) and meniscus, during a fall that results in an ACL tear. The three injuries together are known as the "unhappy triad."
(More information at http://www.skylarkmedicalclinic.com/Skiinjuries.htm)
How do I know if I've torn my ACL?
A tearing ACL has a very distinct feel to it - a popping or ripping sensation from inside the joint. Often skiers will report hearing an audible pop from the knee as the ligament gives way. However, it's also possible to tear your ACL without hearing this audible pop.
Immediate reaction to an ACL tear varies from person to person, but the following symptoms are characteristic of a tear:
- Significant swelling (within a short time of injury)
- Pain (may be immediate, or sink in once the shock of injury has worn off)
- A sensation of instability in the knee joint (may be masked initially if swelling is severe)
If you have a fall and suspect an ACL injury, don't take a chance on it. Talk to a ski patroller and seek medical attention as soon as possible. Clinics near the slope will have a lot of experience with ligament injuries, so your chances of getting a quick and accurate diagnosis are good. This is important so that you can begin an appropriate care regime after injury, and begin looking at some of the options for managing an ACL tear.
As well as assessing your physical symptoms, there are tests that doctors can carry out to check the degree of laxity in the knee:
- Anterior drawer test: http://www.youtube.com/watch?v=yQdBrr3Mmj0
- Lachman test: http://www.youtube.com/watch?v=_5WyoDY31Fc
- Pivot shift test: http://www.youtube.com/watch?v=ZWEGB0ToXZo
Any signs of an unusual amount of laxity in the knee are indicative of an ACL tear. An MRI scan will usually be required to confirm that the ACL is torn, the degree of the tear, and whether other structures in the knee are intact.
MRI showing a complete ACL tear and some minor bone bruising following an injury:
Keep in mind that MRIs, while being an excellent diagnostic tool for these kinds of injuries, are not infallible. There are instances where tears are missed on an MRI but later confirmed via arthroscopy or persistent instability in the knee, and more rarely where an ACL shows up as torn but turns out to be intact. MRIs can only be properly analysed by a fully trained radiographer.
(More information at: http://www.ehealthmd.com/library/acltears/acl_diagnosis.html)
Post injury care
The most important aspect of post injury care is the RICE regime: rest, ice, compression, elevation.
You may or may not need crutches or a supporting brace, depending on the degree of pain you experience from the tear. Most doctors will encourage you to bear weight as tolerated (i.e. walk on it unless it hurts too much) after an ACL injury.
Ice the knee regularly for as long as swelling and pain persist. You may want to consider investing in a Cryo-cuff or similar device, which applies a constant cooling and compression that is very helpful for bringing down swelling.
While the joint is swollen, you should keep it elevated above the level of your heart. This encourages fluid to drain out of the knee, which will decrease swelling. In addition, perform ankle pumps; pointing toes up and down. A tensor bandage can be used to gently compress the joint, which also helps to reduce swelling.
Your doctor should also recommend some exercises that you can do to keep the joint mobile without stressing the injured knee. This include quad contractions to help keep your quad muscles firing, and gentle range of motion exercises like heel slides. Gentle mobilization, for example on a stationary bike with no resistance, is also very helpful for regaining range of motion. You may also want to consult a physiotherapist for a more extensive exercise program, and to work with you as you move from immediate post-injury care into recovery. Avoid activities that cause pain, or stress the injured joint.
Regaining flexion (bend) and extension (ability to straighten the leg) is very important after an ACL injury. If you have swelling and pain in the joint you may find that regaining flexion takes some time, and you probably won't be able to bend the leg normally until all the swelling has gone. Regaining extension is the priority, as full extension is required to walk normally.
ACL injury is often accompanied by deep bone edema (bruising). This can be seen in the MRI scan above as the darker staining on the bones. This can be a source of soreness and discomfort, but usually resolves (albeit slowly - it can take six months or more) over time.
(More information at: http://www.physioadvisor.com.au/9410850/acl-tear-torn-acl-acl-injury-physioadvisor.htm)
Deciding whether or not to opt for surgery is not easy. ACL reconstruction is a common surgery with a good outcome; the estimated success rate is 85-90%. However like any surgery it is initially painful and restrictive, and does require the patient to commit to a lengthy and demanding rehabilitation that can take between 6 months and a year, depending on the graft type used to form the new ligament.
The correct answer to this question will be very dependent on your personal situation, and you should always consult with medical professionals before making a final decision. Your family doctor, a physiotherapist and an orthopedic surgeon (preferably one who specializes in knees) are all good sources for advice. Recovery from injury varies tremendously from person to person, and some people are able to live without an ACL without any restrictions on activity. However, surgery is generally recommended for anyone who wants to continue participating in high level sports such as skiing.
The following section provides an overview of the risks of ACL deficiency versus the inconvenience of ACL surgery and recovery.
(More information at: http://surgicalservicesinternational.com/aclsurgery.html#b6)
Living without an ACL
ACL deficiency: the rule of thirds
Making the decision
- The level of instability in the knee
- The patient’s desire to return to sports or other activities
- The risk of further damage or joint deterioration in the future
Autografts: hamstring, patellar tendon, and quad tendon
Allografts: donor tissue
Synthetic ligaments: LARS
LARS ligaments are the current generation of synthetic knee ligaments, made from industrial strength polyester fibres. These are gaining popularity as an alternative to auto- and allografts, but remain a relatively recent development as an option for ACL reconstruction. Earlier generations of synthetic ligaments were prone to failure in the longer term, leading to serious complications for many patients.
LARS ligaments can be used on their own or as a scaffold for an autograft. Generally a LARS ligament requires the stump of the torn ACL to be in place, and ceases to be a viable option for older injuries.
The biggest advantage of LARS ligaments is that they enable a much faster return to activity than a tissue graft. Many LARS patients are able to return to sports between 3 and 6 months following surgery. Post-operative pain is also reduced because no harvest site is required, and there is no risk of disease. Short-range data (up to 5 years) indicates a very successful outcome for the majority of LARS patients.
However, because LARS ligaments are relatively new, there is currently no long-term (10 years+) data on the success of these ligaments over time. Additionally, LARS ligaments require the drilling of much larger bone tunnels than auto- or allografts, making revision of a failed reconstruction more difficult.
More information at:
There are pros and cons to all graft options, and the right choice will depend on your own preferences, goals, and required timelines. However, a very important factor in choosing a graft is not necessary the graft itself, but your surgeon's expertise with it. Given the learning curve associated with ACL surgeries (see link in section below), you want your surgeon to be confident and comfortable performing surgery with your chosen graft type.
Choosing your surgeon
Depending on your country of origin, this may or may not be an option for you. But if you do have some say in who carries out your surgery, the most important question is how much experience this particular surgeon has in ACL reconstruction. Recent studies have shown that ACL surgery has a very steep learning curve, and the odds of an unsuccessful outcome are higher with an inexperienced surgeon.
More information at:
What to expect from surgery
Generally, ACL reconstruction is performed under general anaesthetic as a day surgery, enabling you to go home the same day.
Because the surgery involves bone drilling, you can expect to be in quite a bit of pain immediately after the surgery. Your surgeon will prescribe pain medication for the first week or so. Be sure to take this on time, and set your alarm so that you can take it on time throughout the night. It's much easier to stay ahead of the pain from the start; if it gets ahead of you, it can be hard to catch up.
Post-operative protocol varies considerably depending on the surgeon, injury, and type of graft used. You may be prescribed a brace to wear for a set length of time after surgery, and advised to spend a certain period on crutches before attempting to weight bear; or you may be advised to start partially weight-bearing as soon as you are able. Your surgeon will also let you know when you should start seeing a physiotherapist, and may give you gentle exercises to do in the meantime.
Your surgeon should provide you with instructions about post-operative care and weight-bearing either before or after surgery. It's very helpful to have a family member present to take notes, as under the circumstances their instructions may be hard to remember! Some helpful surgeons will provide written instructions, but not all do.
For most individuals with a torn ACL, reconstruction will restore stability to the knee. In most cases you will be able to return to previous work and athletic activities without any residual issues. Approximately 90% of individuals return to their previous level of function without any restrictions once proper post surgical rehabilitation has been completed. A protective brace is often recommended when skiing for precautionary measures, at least for the first season back on the slopes.
What to expect from rehab
Remember, surgery is the easy part. The hard work - and ultimately, your successful return to the slopes - depend on your dedication to rehab.
First of all, find yourself a good physiotherapist who has plenty of experience with ACL rehabilitation. Secondly, make sure you follow your surgeon's protocol and physiotherapist's instructions to the letter. The graft will be fragile at first, and the limitations of early rehab - which rapidly become frustrating as your mobility and strength increase - are specifically designed to protect it.
This description is very useful for understanding exactly what happens to the graft after it's implanted in your knee. http://www.kneeguru.co.uk/KNEEnotes/node/1644.
If you live alone, make sure you're prepared to be quite immobile for at least a few days after surgery. Prepare meals that can be frozen and quickly reheated in a microwave or oven; make sure you have a good stack of books and DVDs to keep you occupied. If you live with someone (or multiple someones), make sure they know that you're going to need lots of support. Rest in the early stages is critical to the healing process. Don't make anything harder than it needs to be; sleep downstairs for a few days if your bedroom is upstairs, and don't be afraid to ask someone to stay and help out for at least the first 24 - 48 hours.
Physically, the first few days after surgery are the hardest. You'll spend most of this time lying down with your leg elevated; it's important to keep the knee above the heart (this encourages blood to drain out of the knee, reducing swelling) and to ice regularly. A Cryo-cuff (a simple machine that allows you to continuously cool and compress the joint) is an excellent investment that is worth its weight in gold at this stage, as you can fill it with ice and it's good for 6-8 hours. This saves trips to the freezer for additional ice packs. Don't be tempted to put a pillow under the knee when you're resting or sleeping, even though this is the most comfortable position to be in. This encourages the knee to stay in a slightly bent position, which isn't a good idea when you're trying to regain extension (critical to walking with a normal gait, and one of the most important things after ACL surgery). Putting a pillow or prop under the ankle and leaving the knee unsupported allows gravity to encourage it into full extension.
In addition to pain from the surgery sites, something that's often overlooked is the "blood rush." This is where the surgical haematoma rushes down the leg when you go from a sitting to a standing position, and it causes pain in the calf that can be excruciating. It can't be entirely avoided, but moving very slowly to an upright position will help. If the pain seems unusually severe or persistent, don't hesitate to ask your OS or family doctor to take a look. Excessive pain, swelling and redness can all be signs of a DVT (deep vein thrombosis), so it's worth taking seriously.
You'll most likely experience lots of other additional aches and pains, and sensations so strange you have no idea how your leg could be producing them. (ACL surgery often involves severing a branch of the saphenous nerve, which leads to a lot of very unusual sensations as the nerve responds and regenerates.) Checking in on the Knee Geeks forum is great as a quick temperature gauge as to whether what you're feeling is normal and expected, but again don't hesitate to talk to a medical professional if you have concerns. That's what they're there for, and it's always better to play it safe.
Early rehab exercises focus on regaining flex and extension while giving the joint time to heal. Later exercises work on restoring strength, and ultimately preparing for a return to activity. It's a long process, and at times can seem incredibly frustrating. Remember - it's a marathon, not a sprint, and it will be worth it in the end.
The following is an example of a fairly standard ACL rehab protocol. Your individual protocol may vary quite considerably depending on your surgeon's preferences and the type of graft used in your reconstruction. Remember, your physiotherapist is your best friend in rehab. If you don't feel fully supported, your PT deviates from your surgeon's rehab timeline, or you have other concerns, get a second opinion. It's much better to be safe than sorry.
Phase I: Pre-Operative Phase
a) Restore normal motion of knee
b) Restore normal walking
c) Mentally prepare for surgery
a) Stretching, active assisted range of motion (movement of knee with help), pushing knee into extension (straighten).
b) Muscular strengthening
c) Balance training
d) Other physical therapy activities
Phase II: Immediate Post-Operative (Day 1 - Day 7)
a) Reduce and control swelling and pain
b) Restore full passive knee extension (straighten)
c) Bend knee to at least 90 degrees
d) Walking with brace
a) Active movementof knee through partial range of motion
b) Tighten quad muscles with straight knee
c) Straight leg raises
d) Toe calf raises
e) Weight shifting, small squats and lunges
Phase III: Controlled phase (Weeks 2-3)
a) Maintain full passive knee extension (fully straightened knee)
b) Progress flex of knee to 115-125 degrees
c) Reduce swelling
d) Improve muscle strength
a) Straighten knee with physical therapist helping pushing it straight
b) Leg press and hamstring curls
c) Toe calf raises and wall squats
d) Lunges (forward and to side)
e) Balance drills, stationary bike, pool program
Phase IV: Intermediate phase (Weeks 3-6)
a) Improve leg strength
b) Improve muscle control and endurance
c) Normalize knee movements
d) Perform more functional activities
a) Step-up / step-downs
b) Lunges and squats
c) Leg press and toe calf raises
d) Hip strengthening
e) Balance and endurance training
f) Agility drills in pool
Phase V: (Advanced strengthening phase (Weeks 7-12)
a) Maintain motion
b) Protect knee joint and cartilage in knee
c) Maximize leg strengthening
d) Promote more functional activities
a) Step-up / step-down on balance beam
b) Squats on uneven/unstable surfaces
c) Double and single leg jumps
d) Rotation movements at the knee
e) Agility drills with sideways and backward movements
Phase VI: Return to activity phase (Week 10/12 and beyond)
a) Gradual return to sport activities
b) Continue muscular strengthening and endurance training
a) Lunges and advanced balance activities
b) Elliptical, cycling and running
c) Returning to skiing and other sports
*Must meet criteria set by physical therapist before returning to sport activities.
*Rehab information adapted from Kevin E. Wilk, PT's work
For a comprehensive guide to ACL rehab exercises, see :http://www.kneeguru.co.uk/KNEEnotes/node/775
To brace or not to brace?
This is a tricky question. Studies have shown mixed results when it comes to the efficacy of wearing a brace when returning to the slopes after an ACL reconstruction. The best thing you can do is consult with both your surgeon and physiotherapist, and follow their advice. Remember, a brace is never guaranteed to prevent another injury or compensate for a leg that's not back to full muscular strength; the most it can do is act as an element of extra protection if you do fall or twist your leg.
ACL Smart Skiing
Some excellent guidelines to help you avoid having to go through all of this again:
1) Stay balanced and ahead of your skis. Avoid muscling your turns from the backseat, keep your hands up in the line of sight and stay forward. This will help to keep you off the tails and in a better anatomic postion.
2) Know when to call it quits: avoid skiing well above your level or when you are extremely fatigued.
3) Get in ski shape. This should occur well before the season. Strength, balance, plyometric, and proprioception drills in the late summer (year round really) will give you a good base for athletic skiing. You can find specific drills for skiing and even to guard against ACL injury online.
4) Use the right gear: just because the latest fat ski in a 193 cm is all the rage, does not mean that you are ready for it. Don't be the guy that had to be rescued by patrol 10 into a tree because he turned his bindings up to 17 to impress his friends (true story). Always have your gear checked by a shop!!!
5) Take a lesson. Do it, you can always improve.
6) If you fall, try not to fall backwards.