Knee injuries are a touchy subject for me; I suffered a rather severe patellar tendinopaphy resulting from less than average programming and rather poor biomechanics during a very spicy conditioning workout one Friday evening that my workmates invited me to. The next week I couldn’t even snatch 50 percent of my best without fear of my knee exploding. Two years later, my wife--who happens to be an exercise physiologist specializing in musculoskeletal rehabilitation--and I have experimented with, researched, and trialed every rehab technique, method, programming and theory under the sun (within our budget) to help promote recovery and get myself back to a competing level. All this researching with myself as a case study has helped the vast majority of our weightlifters become pain free with their own knee problems. We now include these warm-up techniques regularly as pre-habilitation or an injury prevention method to make sure our lifters knees’ stay healthy with higher intensity or volume.


Common types of knee injuries and causes

Here is a very basic outlay of some common injuries you may have come across in weightlifting or CrossFit. Yes, there are many more types of injuries related to the knee, and no, this won’t replace professional medical advice and imagery. Part of the reason my rehabilitation journey was so extensive was because I skipped the middle man and went straight to a physiotherapist, rather than seeing a doctor and getting imagery first.) This is just a brief overview of some knee conditions and what they look like in weightlifting.

Patellar Femoral Pain Syndrome – an umbrella term that is used to described pain in and around the patellar (knee cap). It’s used to basically describe knee pain that doesn’t coincide with any other diagnosis or condition. Pain can be different from patient to patient but normally involves pain under the patellar that worsens in full flexion with excessive loadings on the knee: single legged squats are almost impossible and stair cases can also cause serious pain.

Common Causes – increased femoral internal rotation (femur facing inwards), increased knee valgus (knee falling in from the foot), and increased subtalar pronation (loss of arch in the foot)

In weightlifting, all of the above can be easily summarized as the knee falling in.

Patellar and Quadriceps Tendinopaphy – Tendinopaphy is a broad term used to describe one or two conditions: Tendon inflammation (tendinitis) or tiny tears or ruptures in the tendon (tendinosis). Patellar tendinopaphy is used to describe pain in the lower tendon of the patellar usually aggravated if touched and worsens in full flexion or jumping especially under heavy load. Jumping and deep squats can be extremely painful for people suffering this condition. Quadriceps Tendinopaphy is a term used to describe the same or similar condition originating from the upper side above the patellar in the quadriceps tendons.

Common Causes - increased femoral internal rotation (femur facing inwards), increased knee valgus (knee falling in from the foot), increased subtalar pronation (loss of arch in the foot), excessive jumping with poor landing mechanics, and excessive loading in full flexion.

In weightlifting, this can be described as a hell of a lot of heavy snatches and cleans landing with your knees falling in.

ACL Injuries – The anterior cruciate ligament (ACL) can be a common place for tearing, inflammation or over stretching in athletes that play recreational sports, especially women. The ACL is formed in a X pattern along with the posterior cruciate ligament (PCL) between the tibia (shin bone) and femur (thigh bone), and is designed to stop the knee from extending too far, and to help prevent the knee sliding from front to back and back to front.

Common causes – hyperextension (knee joint extending too far) and landing extremely awkwardly following a jump. Some cases have been caused by; yeah you guessed it: the knees falling in.

In weightlifting, this can be described as shit going wrong, really wrong!


What happens following a knee injury?

After an injury or high stress to a joint the body starts a rather fascinating process called arthrogenic muscle inhibition (AMI). AMI is the body’s way of telling you to stop using your bloody knee if you have torn your ACL or ruptured your patellar tendon. AMI is the body’s innate or subconscious response intended to protect the joint from further damage by discouraging its use. It does this by restricting full muscular activation of the surrounding skeletal musculature and sometimes even making them completely irresponsive. Now, AMI isn’t only present after an injury. Mild cases have presented themselves after vigorous massage and/or stretching, so many people can be unknowingly affected by it.

AMI can be an ongoing annoyance for years following if not addressed properly. Injured your knee a few years ago? Unfortunately, this may still be a problem for you.

In the case of the knee, the two main culprits for switching off or becoming lazy following an injury or a serious massage beatdown are the vastus medialis obliques (VMOs) and the gluteus medius (GM) – If you’re not sure where these are refer to the inside of your leg just above your knee for the VMO and your upper, outside bum for the GM.

Unfortunately, these two muscles are particularly important for knee stability in the squat and pull, even knee stability in general. The VMO is responsible for correct tracking, alignment and stability of the patellar – in particular when the knee is being bent and straightened, so it’s an important one for knee health. The GM is responsible for externally rotating and abducting the femur, so its main job is to get those knees out in the squat and pull. I’m betting more than half the people reading this article have heard the good old “knees out” cue – yep, that the GM’s main role, therefore it’s another very important one for knee health, and one of the main culprits (if weak or inactive) for initial knee injuries (remember most of the causes for knee injuries above: knees falling in!)


Load Sharing and Proprioception

Another problem that arises from AMI and the surrounding muscle groups becoming lazy is load sharing. Skeletal muscles share a substantial amount of load and stress when they are active, if they are inactive, they basically don’t.
This process helps distribute load and forces evenly to the appropriate areas in the body that are capable of handling these forces. Can you imagine what happens following AMI with a knee injury? GM and VMO decided they can’t be bothered working anymore so all the load they were designed to share and transfer now ends up being directed elsewhere – you guessed it, straight into the knee… 5RM back squat with most of the load in your knees: ouch, mine hurt just thinking about it. Research on how much load and stress certain muscles actually take or distribute during a squat below 90 degrees is hard to come by, but I can tell you now, it’s a lot! In a bodyweight ass to grass squat, you are looking at somewhere between 4.7 and 5.6 times bodyweight of vertical forces and 2.9 to 3.5 times bodyweight of horizontal forces through the knee joint. If your GM and VMO weren’t working particularly well, your knee would not only be taking all that load in a compromised position, but probably amplifying it as well due to the fact they aren’t helping share any of the load.

Proprioception comes into play with all of this and plays a big part in injury prevention. Proprioception is the process in which the body can activate or vary muscular contraction in immediate response to a signal or information coming from external forces- basically your total body awareness and control. For example, if all your muscles are working and adequately strong enough, all the incoming signals to your brain and proprioceptive system should activate all the right musculature during a squat in order to track your knees, hips and ankles into a safe and efficient position. If your muscles aren’t working properly, that proprioceptive system either doesn’t receive the right information in order to activate the right musculature, or it can’t send the right information to the right musculature because of our old friend mentioned earlier: AMI.


How to get them working properly again

I’m a coffee fan; I’ve been tempted to try an intramuscular caffeine injection to see if it will wake these two lazy muscles up and get them to perform their job again. Shame that won’t work… or will it?

Another way to give these muscles their dose of muscular caffeine is called palpation. Palpation is a poke, a prod, a rub, in or on the muscle you’re trying to activate, it’s whatever it takes to tell your mind that muscle is there and it should be activated. It can be a difficult process if the muscle has been dormant for some period of time. It may start as a flicker of activation or even nothing at all. Persistence and discipline is key for regaining proper muscular activation back to a subconscious level. To start with it will have to be a very, very conscious effort performed with very, very simple exercises combined with palpitation and concentration in order to get them to start working again – It takes time for you to get in the zone and be productive at work or on the platform right? Same with these inactive muscles, it will take time and patience.

Where do you start? For the GM, you can start with a very basic clam exercise with a light band around the knees, lying on your side. Externally rotate the knee only a few inches from the other without your hip twisting: Feel for the GM working. If it’s lazy, sporadic or fires late it will need some palpation. Poke prod and rub the GM before the next attempt, if the muscle is already strong and just lazy, after a few reps you should notice a serious improvement in activation which will transfer directly over your squat. If it’s weak and inactive, it will be a long disciplined process for you to reactivate and strengthen these suckers up. It will have to start with 3 sets of 4 reps of the clam daily, slowly scaling up to 3 sets of 15 with no problem in activation or strength. Once that has been achieved you can progress to bodyweight squats or lunges with a band around your knees, still making sure it stays active throughout the whole movement.

The same process can be done for the VMO but with a different leg lift exercise. Sit down or laying down with your leg extended and externally rotated in front of you. Without shifting from the hips or rocking/twisting, lift your leg straight from the ground only a few inches. Feel the VMO. Again, if it is inactive or lazy, you can venture down the same process of palpation and strengthening to get it active again, slowly progressing once again to the bodyweight exercises making sure it stays active.

These are only a couple of basic tools used to help correct muscular inactivity. There is a vast array of exercises and techniques that can be used by exercise physiologists and physiotherapists to help this process and for that reason I’m going to avoid going too in-depth with the rehab/prehab exercises and how they should be done: that’s up for you and your coach or you and your health professionals to decide. I will say, however, that these simple activation drills in your warmup can seriously improve your knee health and stability by activating all the right musculature to keep those knees in a biomechanically safe position. It’ll also help develop the ability to share load evenly throughout the knees and hips. Don’t forget what can happen if your knees fall in!

Even if you haven’t hurt your knees, you more than likely fall into the group of those people who have inactive glutes and lazy VMOs from the postures and habits of today’s society. Try including these basic drills and activations into your warm-up. It only takes a couple extra minutes and it may just save and strengthen your knees for future PRs.

References:
William D. M & Frank I. K “Exercise Physiology” 6th ed. 2007
Peter B & Karim K “Clinical Sports Medicine” 3rd ed. 2009
Robert S. W & Daniel G “Foundations of Sport and Exercise Physiology” 4th ed. 2006