Barefoot running, Chi Running, and the 3 Laws of the Kinetic Chain

A good friend recently asked me what I thought about Chi Running.

I like it.

Chi Running is one of many approaches that teach runners to run softer and absorb more forces in their proximal muscles.  The idea is that by having a strong core, particularly in the buttocks, less forces will be absorbed in structures that are not designed to handle high loads, including the knees and back.

This is similar in many ways to barefoot running.  Not everyone can handle barefoot running, but for those that do like running barefoot, the reason it works is that it teaches you to run more softly.  When you run with a heavily cushioned shoe, you can hit the ground with a very forceful heel strike.  This is not possible when you run barefoot- it simply would hurt too much to slam your heel into the ground.

This is, in my opinion, the reason why all the new barefoot simulator shoes on the market (including MBTs and Skecher Shape-Ups) can be helpful- because they have a rocker bottom sole, if you try to have a forceful heel strike, you roll forward, which dissipates the force.

Back when I was a Sports & Spine fellow in Chicago, my colleague (the late, great Jim McLean) and I noticed that we could explain essentially every musculoskeletal condition through 3 very simple rules, which I now refer to as "3 Laws of the Kinetic Chain":

1. Forces have to go somewhere

2. Range of motion has to come from somewhere

3. If the body cannot absorb forces or obtain range in a way that is anatomically appropriate, it will do so in way that is pathological

A great example is running with bad form.  Every time your foot hits the ground when you are running, the ground pushes back against your body in what is called a ground reaction force.  This ground reaction force can be several times your body weight, and it doesn't just disappear into the ether- those forces have to go somewhere.

So where do you want those forces to go?  Ideally, you want those forces to go into the biggest, baddest muscle you got- that is the gluteus maximus (your butt).  Other good choices are the quadriceps (the front of the thigh) and gastrocnemius (the diamond shaped calf muscle).  The more you can train your body to absorb forces into these structures while you run, the less force will be transmitted into your spine, hips, or knees.

Barefoot running is a method where your body will naturally train itself to use these muscles, because if you try to run by slamming your heels into the ground, it hurts too much.  This works ok if you can adjust your stride appropriately, but many people find this too painful to tolerate.

Some commercial products, most notably the Vibram 5-Finger shoes, have been developed that help protect the feet while you are barefoot running.

Chi Running is an approach that helps teach you to engage your core while running, which is the same general concept.  As a general approach, I think it is fine.  If I was seeing a patient in my Sports & Spine clinic, I would try and see if I can be more specific as to exactly which muscles the patient should engage, but as a first iteration, Chi Running is a very reasonable approach.

Practicing being joyful

Several years ago, I went to a fantastic course on myofascial medicine, and it's had some major impacts on the way I think about musculoskeletal conditions.

During the course, my friend David Lesondak shared with me an amazing concept-  that we need to practice being joyful. I thought that this was a remarkably brilliant insight

The nervous system is designed to adapt to anything you do frequently as a "new normal." This can have negative consequences if you look at people are who routinely miserable. As a thought experiment, think about the last time you were at the Divison of Motor Vehicles. It's a miserable environment, everyone hunches their shoulders, and there is a palpable tension in the room. Now imagine being like that all time- that would be a horrible "new normal."

Instead, imagine trying to practice a "new normal" by practicing being joyful. Here's a simple exercise- extend your hands overhead like you just crossed the finish line of a marathon. Didn't that make you feel better? I don't think it's possible to put your arms overhead in a victory position and be in a bad mood.

I don't think this is just psycho-babble- I think it reflects a real neurologic phenomenon. Paul Ekman did some ground breaking research that demonstrated that if you have a person put their face in a smiling position, their mood will improve. I think that this is true of the body as a whole as well- if you place your body into the position of happiness, you will feel happier.

I've noticed this when I work on some strengthening exercises in my patients. I often work on them to strengthen their posterior chain (muscles behind their back like the thoracic paraspinals) and stretch their anterior chain (muscles in the front of their body, like the pectoralis minor), and an interesting ancillary phenomenon is that most of them notice that they are noticably happier. It happens almost instantaneously. I don't think this is an accident- by training their muscles so that they can literally walk taller, they also figuratively walk taller- they become happier.

And so do I.

The Importance of Walking Speed

If you meet a person, and you want to know how much longer they will live, and what their remaining quality of life will be, what information would you want to know?

If you ask most physicians this question, they may answer something along the lines of whether they have cardiac or pulmonary disease.

Turns out, though, that a better way to answer the question is to assess their functional status.  The two most important factor that determine future quality of life are age and gender (women do better, which will be a topic for another day).  The third most important factor, perhaps surprisingly, is how fast does the person walk.

Walking speed is a great functional measure.  It's easy to measure, and captures a lot of information in a way that makes it a terrific summary measure.

For example, there are many older individuals who have multiple medical morbidities- diabetes, heart disease, high cholesterol, hypertension.  I probably know 100 people like that, and even if you are not a physician, you probably know many people who fit that profile.

Even with all those different disease states, they can be very different functionally.  If I meet two people who are aged 70, one can be a "young 70" and another can be an "old 70."  Walking speed is a great way of distinguishing which is which.

For those who want to learn more about the importance of gait speed in assessing health status, I encourage you to look up the research from Stephanie Studenski.

For the lay public, I would simply self-monitor the gait speed of yourself and the people you care about.  If you have an older loved one, and you are trying to figure out whether they are healthy and how long they will be able to stay independent and take care of themself, monitor how fast they walk.  That is more valuable than just about anything else in assessing how healthy they are.

Great Forbes article on the downsides of "doctors pushing buttons"

The number 1 patient complaint I hear is "I wish my doctor spent less time listening to me, and more time pushing buttons." .....

Of course I never hear that.  Patients want their doctors to listen to them.  This recent article at Forbes goes into details discusses how pervasive the problem is- it's a really big deal.

Every physician I know wants to be a patient advocate.  From a patient perspective- we need YOU to be your physician's advocate, by voting and writing for your congressman.  If you want your physician to listen to you more, we need you to help us, by stop having government requirements force us to click buttons.  Enough is enough!

Annular Tears

Frequently asked questions about annular tears:

1. What is the disk?

- The intervertebral disk is a structure that provides mobility  between the bones of your spine.
- It is best to think of the disk as a gasket or ball-bearing that aids in motion.

2. What are the parts of the intervertebral disk?
- Outer fibrous layer, called the annulus fibrosis (annulus)
- Inner gel layer, called the nucleus pulposus (nucleus)

3. How does a normal healthy disk work?
- The disk is a pressurized system which allows motion. 
- The nucleus contains gel that allows for motion
- The annular fibers provide structural support for the nucleus

4. What is a herniated disk?
- A herniated disk (sometimes called disk protrusion or disk extrusion) is when the gel in the nucleus pushes outward, stretching or breaking through the annular fibers
- A herniated disk can be painful if it pushes on a nerve root. This may cause pain that shoots down your limb (often called radiculopathy or "sciatica")

5. What is an annular tear?
- An annular tear is a tear in the annular fibers
- It can be identified on an MRI as a "high intensity zone." This is a bright area that is seen in the otherwise dark disk as shown in the picture below.  (The annular tear is in the white dot in the back aspect of the second disk from the bottom as indicated by the black arrow)

The MRI image above is called a sagittal slice, which is a slice through the middle of your body (separating the left and right side of the body).  The left side of the screen represents the front of the body, and the right side represents the back of the body.

The image below is from what is called an axial slice, which is a cut through the body separating the top and bottom of the body.  This image is specifically through the L4-L5 disk.   In the center of the screen is an oval structure with a whitish center and black outer rim- that is the disk.  The whitish center is the nucleus, and the black outer rim is the annulus.  Within the annulus, there is a thin white line toward the lower part of the annulus- that is the annular tear (indicated by the white arrow).

6. Are a herniated disk and an annular tear the same thing?

- No
- They can co-exist, but they can also occur separately
- A simple (and mostly true) way to think about it is that annular tears cause low back pain, herniated disks cause pain that shoots down the limb when it pushes on a nerve root

7. What are the symptoms of an annular tear?
- Stiffness in the low back when waking in the morning
- Vague pain that is difficult to localize
- Pain putting on shoes and socks in the morning
- Pain with prolonged sitting
- Shifting positions while sitting
- Tendency to axially off-load while sitting (e.g., using straight arms with a fist to push yourself off the table)
- Improvement in symptoms when walking following prolonged sitting (e.g., when first stepping out of the car after a long car ride, once you have straightened out)
- Pain with Valsalva maneuvers (e.g., coughing, laughing, sneezing, sexual intercourse, and bowel movements)

8. What about muscle spasms?
- Muscle spasms are sometimes experienced along with annular tears and herniated disks. However, they can be seen in the absence of a herniated disk or annular tear.
- Muscle spasms are often not the primary source of pain.

9. What is the treatment for an annular tear?
- Physical therapy
- Injections, such as epidural steroid injections can be a useful complement for physical therapy.  One particular approach, called a transforaminal approach, may be more effective than other alternative approaches that are more commonly used.
- Medications, such as oral steroids can be used early on in treatment course.  We find that transforaminal epidural steroid injections below the level of the disk injury, however, tend to work better than oral medications.

Musculoskeletal Ultrasound

One of the underrated tools that Drs. Chimes and Hyman have at their disposal when diagnosing and treating patients is the use of musculoskeletal ultrasound.

Most people are probably familiar with ultrasound to some extent, physical therapists will often apply therapeutic ultrasound to injured tissues and ultrasound is typically used to visualize unborn babies. Musculoskeletal ultrasound  is closer to the ultrasound utilized during pregnancy, the idea being that the probe emits super high frequency ultrasonic waves which go through a gel medium before being transmitted through the skin and different body tissues (such as muscles and tendons) before bouncing back and being received by the probe.

The frequency of these ultrasonic waves produces an image that is incredibly high resolution (3 times higher than MRI). The ability to view these images in real time is unique compared to other imaging modalities, allowing the doctors to observe the dynamic movement of body structures. An additional benefit of this is the ability for the patient to give feedback in real time, this is important because it is clinically significant whether or not the patient is experiencing any pain at the location of the probe where inconsistencies are observed. This can help the doctors discern whether the irregularities are concordant with their symptoms or simply incidental.

Patients will often come into our office and state that they have had a previous cortisone injection performed by another physician. While they probably did have a corticosteroid injected, that isn't really the relevant detail. More important is where the medication was placed, and how it got there. Historically, and the way that most physicians today do these injections is on a landmark basis. What that means is the doctor will insert the needle and once a landmark is reached (often when the needle hits a bone), then the placement of the needle will be adjusted relative to that landmark before the medication is injected. While injections done with this method can give patients relief, this technique doesn't completely take into account the variety in each person's anatomy or allow for the precision required to reliably hit the intended target. Even if the target is missed, it is likely that the medication was somewhat absorbed by being injected in the general area, giving the patient variable levels of relief.

Having the ability to use musculoskeletal ultrasound to guide these injections has been shown to dramatically increase the efficacy of these injections (check out these two articles). The ultrasound machine allows the target structure and the needle to be visualized in real time, which has multiple benefits. First, by seeing the needle in real time, landmarks do not need to be used, making the procedure more comfortable for the patient by allowing the physician to avoid having the needle touch down on bone, which can often be quite painful. Another advantage of using ultrasound is that the needle can be more precisely directed towards the target, allowing the doctor to know exactly where the medication is being injected. This can be helpful in a situation where the injection doesn't offer the patient any relief, allowing the doctor to definitively rule out that particular structure as the pain generator.

Let's use shoulder pain as a common example.  The supraspinatus is a structure that can contribute to shoulder pain in many patients. One example of an injection where the benefit of ultrasound is obvious is a subacromial bursa injection where medication is injected into the subacromial bursa directly above the supraspinatus, bathing the tendon in medication. The placement of the medication is especially important because if the medication were to be injected directly into the tendon and there was even a small tear present, it could lead to even further degradation. The subacromial bursa itself is maybe a millimeter or two thick, smaller than the width of the average needle used to inject it, as you can see in the images below. You can see how even the best sports medicine physicians in the world would have trouble reliably hitting this target when using a landmark based technique.

This is an width of the average needle used to inject medication. You can see how small it is.

As you can see in this ultrasound image, the bursa (indicated by the arrow) is a very thin fluid filled sac smaller than the tip of the needle

Scapular rehab exercise series

This link contains a great series of scapular rehab exercises we recommend for patients with shoulder pain.

The article that describes the thought process behind these exercises can be found at this link, which I wrote with one of my former residents and one of my former Sports Medicine fellows.