January 2, 2015
Le’Veon Bell suffered a hyperextended knee this past Sunday night and is questionable for the Pittsburgh Steelers matchup vs. the Baltimore Ravens. I will break down whether he will play and how effective he can be with this type of injury. (During editing of this post, Le’Veon Bell has been officially ruled out)
A hyperextended knee is not all that uncommon among athletes that play contact sports, but the average person has likely never experienced a hyperextended knee and especially not the traumatic type like Le’Veon Bell suffered. In medical terms hyper means over or beyond and extension means to straighten. Therefore hyperextension refers to the act of the knee straightening beyond its normal position. In essence the knee bends backward either due to trauma or in some cases due to a force or momentum that is put on the knee by intrinsic or extrinsic forces.
Most of us don’t experience this type of injury because we are never exposed to such forces and furthermore when we are exposed to force that would bend our knee in the wrong direction, there are a few barriers that stop hyperextension from occurring. The first line of defense being your hamstring musculature. The hamstrings are the primary muscle group that bend the knee in the correct direction, but they also resist the knee being bent in the wrong direction. Additionally the ligaments of the knee act as another line of defense to prevent the knee from going beyond its normal limits. The Posterior Cruciate Ligament (PCL) would be the primary limiter against hyperextension. While these ligaments and musculature help prevent hyperextension, they are also at risk for injury during this act of protecting the knee.
The anatomy of this injury is hopefully fairly simple to understand. However, the recovery from this injury and whether Bell can play this weekend is a little more complicated. An injury like this has layers that go beyond simple concerns like pain tolerance and getting the knee strong enough to play. Le’Veon Bell and the Steelers will need to be attentive to whether Bell can play this week as their primary concern, but with this being the playoffs they will need to look at making sure they don’t lose him for the rest of the playoffs. While this injury does not typically include any long-term fears for the health of Bell’s knee, there are some short-term issues that make this a situation that needs to be managed just right.
To explain more clearly I will use an injury that is more common; the ankle sprain. Many more non athletes or recreational athletes have suffered an ankle sprain. For many, the first ankle sprain leads to a second ankle sprain and for some who are less fortunate it leads to ongoing ankle sprains. Even for those who don’t sprain the ankle again after the first injury, you can appreciate the instability following and ankle sprain when placing that foot on the ground or a surface like grass or gravel. An ankle sprain is not all that different from a hyperextended knee as it is still simply a joint that is enduring more motion than it should in a particular direction. With a sprained ankle, we are many times over stretching our ankle everters (muscles) and our anterior talofibular ligament; while with a hyperextended knee we are over stretching our hamstrings (muscles) and our Posterior Cruciate Ligament (PCL). In fact, a hyperextended knee is really just a sprained knee; just like you would say a sprained ankle. The sprained ankle is notorious for its recurrence, and this is not due to plain old bad luck. There is a scientific reasoning for why people re-sprain the same ankle and this same rationale is essential to the plan for Le’Veon Bell’s return.
In my opinion the three most important words for the Pittsburgh Steelers this week are Somatosensory, Proprioception, and Mechanoreceptors. These are not the common words that you will hear on all the ESPN and NFL network updates, but trust that Bell’s return should be centered around these words. These words are all related and based in neuroscience. In a way they are just three big fancy words that you can use to sound smart that all lead to a similar place of reasoning.
Somatosensory refers to the Somatosensory system. This is the system that informs us of our external environment, our body positioning, and other stimuli. Your Somatosensory system processes just about everything ranging from telling your brain that the water on your hands is too hot to telling your hamstrings to contract because your knee is being bent too far backward. You use this system all the time unconsciously and without it we would all be in a world of trouble.
Proprioception can grossly be viewed as a child of your Somatosensory System. Proprioception is more specific to muscles, joints, and extremities and is a big part of how we know where our body parts are without looking at them. I do a lot of work with the geriatric population and much of the reason seniors are falling at an alarming rate is that many are not utilizing proprioception, and are completely depending on their vision for walking. When you walk, proprioception is what tells you that you are putting your right foot in front of your left ; or allows you to adapt to walking on grass without losing your balance. In the absence of proprioception, we would all be walking and looking at our feet to make sure they went where we intended and when walking on grass we would be intently watching every step to analyze the change in surface.
Mechanoreceptors are the sensory receptors or data collectors for proprioception. Your muscles and tissues have these sensory receptors in them to collect the information of how they are being distorted, or how they are receiving pressure and this information translates into the proprioceptive abilities I described above.
All of this neuroscience talk is a big deal for Le’Veon Bell and any one else recovering from a sprained knee or ankle. During the process of injury, the muscles and ligament are obviously stretched. The less obvious observation is that the mechanoreceptors in the area also suffer injury. This mechanoreceptor injury has a domino effect. Without functioning mechanoreceptors, Bell will have some proprioceptive deficits which means that his knee may not be as precise with knowing when its extended to 0 degrees or when it is moving into hyperextension. Similarly to with the common sprained ankle, the ankle and foot may not be precise with knowing whether the foot is completely flat or slightly turned in. When this occurs with the ankle, you may put your foot down while its turned in and just like that you have re-sprained your ankle. For Le’Veon Bell’s knee, he may plant his leg thinking his knee is bent 5 degrees when in fact it is extended beyond 0 degrees and just like that he will hyperextend it again.
With his mechanoreceptors and proprioception operating at a deficit, we can conclude that his Somatosensory system is also working at a deficit. For a running back this is bad news as his activity during a game is unpredictable and he has to depend on his body and his neurological systems to react and keep up with his moves. Many other football positions have more routine and will not challenge the Somatosensory system as much; such as quarterback, who if protected will make his drop and throw, or turn and hand off; or a wide receiver who knows exactly where to go before they do it. As a running back, Bell has to react all game and if his Somatosensory system is not on point, there is a good chance he hyperextends that knee again.
With all that said there are some remedies that can protect Bell from re-injury. The most straight forward remedy is a knee brace with a dial lock that would not allow his knee to extend beyond 0 degrees which would protect him from hyperextension. That may seem like a no-brainer to some but for a dynamic back like Bell, this would likely feel like a hinderance to his agility. Taping is another option. Taping is a way to give increased support to a particular area that may not be at full strength. In this case we can assume that Bell suffered some excess stretching to his distal hamstring fibers, and re-enforcing that area may give him more stability if his knee tries to hyperextend.
What you need to know
First and foremost what you need to know is that these athletes and these medical teams in the NFL are special. DeMarco Murray completely proved me wrong to the 4th power and to some extent his situation humbled me to respect how continuous the progressions in healthcare are, despite the fact that I am a part of it. I would estimate that the NFL is 5 to10 years ahead of the most progressive parts of our country in regards to medicine.
As I am editing this post, I hear that Bell has been officially ruled out. Now to be truthful, I was going to write that I thought that he would play and that he would wear a brace. Ultimately I was projecting him to be more of a decoy and expected a somewhat poor performance and possible re-injury. I agree with this decision by the Steelers to hold him out. The Steelers are likely smart to do this, as if they are to move on in the playoffs, which is quite possible considering the injuries the Ravens have in the secondary, they will need Bell in the line-up. This injury should likely be a 2-3 week recovery process and with the playoffs accelerating the healing time, I think there is a good chance that Bell will be available for whoever the Steelers get after the Ravens.
For those playing daily fantasy, the play is definitely to start Big Ben and Antonio Brown as the Ravens are poor vs. the pass and very good vs. the run. With Bell out, this game is almost exclusively in Big Ben’s hands. I think we will all keep an eye on Bell’s recovery if the Steelers advance, but I would expect him to play if they do; maybe with a brace or maybe without.