Notes from Kevin Wilk's "Coffee and Cases" Sold-Out ACL Workshop
MORE ACL?! Yes, I agree, we are battered with ACL rehab information, and physical therapists like to believe we got it down. Well. We don't. Why has the prevalence stayed the same all these years? We have a lot to learn, but here's some information to make your rehab as efficient as possible. Don't take a shotgun approach!
During the APTA Combined Sections Meeting, I got to wake up at 530am to attend Kevin Wilk's "Coffee and Cases" workshop on the ACL. Here's some key points. I'd like to credit him for ALL this information, and that you can access his information for free on his website at www.kevinwilk.com.
Before we talk about the rehab process, we MUST understand the surgery itself. If you have not seen one, I recommend Youtubing it. This post will go more in-depth.
To start, an ACL surgery can not replace the angle of a native ACL graft. If you look at the picture below (sagittal view of bisected femur), notice how posterior the ACL is within the condyle of the femur. During ACL surgeries, a hole is drilled into the femur, but it will not mimic the original angle (it will always be more anterior).
Because of this, surgeons often do the anterior drawer test after the graft is in to check sturdiness. It will test negative, however due to the new angle of the ACL, lachman's test may often test positive.
Next we look at graft options:
- Patellar: This graft tends to heal best because it is bone-tendon-bone. The bone can better fuse with the tibia and femur. Additionally, it is the most common graft used for the youth.
- Hamstring: This graft can be very long allowing a surgeon to fold it multiple times to make it twice as strong as your native ACL. Due to them taking it from your own hamstring, you can not be aggressive early on because the hamstring can not assist in stabilizing your knee due to the surgical trauma.
- Achilles: This is often taken from another body (cadaver), and is the strongest. Although it is the strongest, it has poor healing potential compared to the other because it is not of your own body. It failed in 44% of active people, and is 4x likely to fail compared to an autograft (from your own body; patellar or hamstring).
Next, we discuss the surgeons. There are GREAT surgeons who have great outcomes due to their experience in the surgery and the rehab process itself. However, here are some stats:
- 147,000 ACL reconstructions performed a year.
- 85% of surgeons who perform these surgeries only do 10 ACL reconstructions a year.
- #1 reason of graft failure is that the angle of the ACL graft not optimal
Next we talk graft healing. Ligamentaization is when the tendon of the graft actually turns into a ligament. In 12-months post-op, only 50% of the tendon is ligamentized, yet that is the same time most athletes return to sport. Looking at the slide below, we see that it is nowhere near the strength of the native ACL if you multiply all the grafts' strength by .50.
What about the achilles graft? Yes, it is just as strong, however remember that it does not heal as well as the other as mentioned earlier. At 2-years the grafts may be 70-100% as strong as the their maximal strength.
So what's this all mean? both for someone going through surgery, or a physical therapist rehabbing it, LATE STAGE REHAB IS KEY! Once protocol allows, you have to load it right and get it moving in proper progressions of velocity.
Below are some clinical pearls in rehabing throughout all stages:
- You have to get swelling down in order to get extension. Key during early rehab is to decrease swelling and get that extension.
- To get extension, prone with leg hanging off the table is not optimal as the hip may rise causing the knee to be slightly bent.
- Mobilization may not be best because the capsule in that area is so thick. Instead, stretch and manage inflammation.
- NMES is still a very good way to get the quads working, both in the literature and clinically.
- To get the quads activated, do closed chain knee flexion with the knee at 60 degrees isometrically. This has the maximum EMG activation of the quads, and puts nearly 0 stress on the ACL.
- You can use the leg press between 45-100 degrees. Yes, you can have them squat, but most people can't squat properly. Are you really going to teach them a squat while they are recovering from a knee surgery?
- Brain imaging shows inhibiton of the cerebellum and motor cortex on the contralateral side of the affected knee. Doing some exercises with their eyes closed can train these areas of the brain as they will get a better sense of their body.
- Prehab shows substantially better outcomes for quad strength, however it's hard to decide whether people should use their insurance visits before surgery or after.
I hope that helps you rehab your knee, or you rehab your patient's knee. Additionally there's A LOT of new ACL research coming out. If you're on Twitter, join the talk. I recommend following Dan Lorenz, Tim Hewett (he has 3 accounts...just follow 1), and Amy Arundale. Here are some of the discussions going on:
- Research showing fatigue DOES NOT increase risk of ACL tear. There's only a few studies showing small correlation. This will likely be a debate or session at CSM 2018.
- Perturbations during gait training does not decrease secondary ACL tear 1-2 years after reconstruction. I would still incorporate static balance exercises, since there's a lot of evidence to show proprioception decreases after ACL reconstruction.
- Return to sport for ACL should be a 2-year plan. This is controversial as athletes get paid millions to compete, with a few people not having secondary ACL injuries. However, there is some very interesting debate about it.
What You Should Watch: How to Teach the Single-Leg RDL
One of the most common exercises done wrong is the Single leg RDL. People have their hips way too open which works the adductors rather than the hip extensors. EXOS provides a great regression for people to understand the movement. This is one of my staple exercises to get them doing loaded reps.
What You Should Read: Environmental Adjustments for Behavior Change
Healthy behavior is hard. Everyone knows the benefits of good eating habits. It's the behavior aspect that is hard to change. Check out the NSCA's article on some adjustments you can make.
Click the picture above or the link here.
Vien is Doctor of Physical Therapy Student and also a Certified Strength and Conditioning Specialist through the National Strength and Conditioning Association. He has 6 years of experience training youth, college, and pro athletes in 1-on-1 and team settings. He has shadowed several Strength and Conditioning Programs in a addition to having clinical rotations in sports settings.