By Chris Howson DC
There has long been a general trend in healthcare toward more and more specialization. In some instances this is important, such as looking at surgical care of very intricate organ systems. However, this myopia can also be problematic in my opinion, as it’s easy to “miss the forest for the trees,” as the cliche goes. This is especially true in what I consider musculoskeletal medicine - namely chiropractic, physical therapy, sports medicine. In contrast to hyperspecialization, the concept of kinetic chains and regional interdependence is based on the impact different joints can have on each other and on the locomotive / musculoskeletal system as a whole. It focuses on seeing the whole picture, not just a thin slice.
When I was in chiropractic school in the early 2000’s, we were taught that in an extremity complaint a competent physician will check the joint above and below the one in question as well as the chief complaint. I associate this concept with a lecture regarding hip pathology causing knee pain, but this might not be an accurate memory. However, at that time I had never heard of FMS or Gray Cook. I had heard of Anatomy Trains and even owned a copy, but it was a little more “out there.” Spinal complaints were spinal complaints, extremity complaints were something of an afterthought. In the almost 17 years since I graduated from Northwestern, though, the lines between complaints have blurred and I can’t help but find myself in awe of the interconnectedness of the musculoskeletal system. The purpose of this article is to describe some of the patterns of dysfunction that I find myself addressing on a daily basis. I’m sure this is review for many, but even on a 3rd reread I sometimes pick up something I’d missed previously. I will break this down into two main parts, lower body and upper body. Obviously there is crossover between the two areas, and our colleagues who treat baseball players and golfers have some excellent resources concerning this. I practice in North Dakota, and I have the privilege of treating many ice hockey players of all ages and levels. In the spirit of hockey injury reporting - we’ll go with “upper body injury” or “lower body injury.” The remainder of this post will be dedicated to the latter.
Lower body injury
The most unique feature of human anatomy is our bipedal specialization. We are the only species on earth that is obviously designed to stand and locomote in an upright, bipedal posture. This presents many challenges, one of which is maintaining this posture while shifting the load of our torso from one leg to the other and balancing in a cantilevered position. A man made structure built with its base offset like that of a human on one leg would collapse. However, we spend 85% of our time on one foot only while walking (according to Janda), and far more when running. Even in patients with a distinct Trendelenburg gait they still don’t typically collapse. This speaks to another amazing human specialization - the ability to compensate.
Compensation can take many forms. The forms I’m going to focus on here include muscular substitution and recruitment. It is important to grasp the concept of reciprocal inhibition when considering the interaction among muscles, joints, and motor chains. Reciprocal inhibition, sometimes referred to as reflexive antagonism, is defined as the spinal process of inhibition of a motor neuron pool when the antagonist motor neuron pool is activated (Mark Hallett, in Aminoff's Electrodiagnosis in Clinical Neurology (Sixth Edition), 2012). I use the following analogy when describing it to patients: “if you flex both your bicep and your tricep nothing moves; in order for one to fully function the other has to shut off.”
As part of my pursuit of the orthopedic diplomate, I had the privilege of taking Dr. Tim Bertelsman’s course in which he addressed lower extremity issues. I can’t recommend it enough. Dr. Bertelsman traces many common lower body complaints back to gluteus medius weakness. He does a great job of describing how the failure of the gluteus medius to provide stability in single-leg stance allows internal rotation of the femur at the hip and knee, internal rotational stress on the knee, and can function in causing over pronation of the foot / ankle complex leading to complaints such as hip impingement, ITB syndrome, medial and / or anterior knee pain, plantar fasciitis, etc depending on each person’s individual presentation. This description meshed perfectly with the patterns I’d been encountering in practice and expanded my awareness of lower body issues. He taught the single leg squat test to evaluate gluteus medius function, a practice I then adopted.
When Covid-19 struck and I suddenly found myself with more office time than I’d ever before had available, I took the opportunity to attack Dr. Craig Liebenson’s newest edition of Rehabilitation of the Spine. Among the countless gems in this work, one concept that really hit home was the ability of overly tight hip adductors to cause reciprocal inhibition of the gluteus medius. The little cartoon lightbulb floating over my head lit up. I’d previously developed a theory that substitution of the gluteus medius for the gluteus maximus in causes of so-called glute amnesia was a typical culprit in hip dysfunction. This new focus on the adductors jived with my own experience of driving hip extension with my adductors and research I’d done regarding hip function that reported that the adductors have the ability to produce as much power in hip extension as the gluteus maximus. The same section of Rehab of the Spine described using the reflex facilitation of the hip abductors in response to an overhead hold to determine between abductor inhibition and frank weakness. I mention the origin of several of these concepts for a number of reasons: one is to give credit where it is due and not give the impression that this is all my own work, another is to demonstrate how practicing with an open mind and open eyes causes one’s approach to change over time. I believe this type of experience is far superior to the dogmatic following of any one guru’s “method.”
My years of working with hockey players and athletes of all types had long ago acquainted me with hip flexor tightness and the effects it can have on movement. In fact, it even led to the development of the Drop Release instrument, the tool I invented to help combat the imbalance in agonist/antagonist muscles. Another key component of lower body function came from Shirley Sauermann’s “Diagnosis and Treatment of Movement Impairment Syndromes” in which she details the anterior femoral glide syndrome - evaluated by palpating the greater trochanter during SLR (it should stay put as the femoral head glides to accommodate hip flexion) as well as the relationship between overly tight hip rotators and lower back pain (easily demonstrated by passively rotating the hip of a prone patient - in those with tight hips the lumbar spine will rotate early in the movement rather than only at the end range of hip rotation).
With a decent understanding of the above concepts, I now had a more complete clinical picture that applied to a large percentage of my patients who presented with lower body complaints.
In lower body complaints (lumbar spine and distal), I focus on evaluating and normalizing hip function. As it is such a mobile joint and so important in locomotion, the hip can and does influence the spine and pelvis above it as well as the extremity below. This evaluation doesn’t always take place on visit one, as acute pain must be addressed to allow a true picture of underlying function to emerge. But in nearly all cases I treat I eventually evaluate this chain of function / dysfunction, especially if the chief complaint is recurrent.
I will attempt to make sense of my flow and thought process as I work through the above issues. As with everything we do, this is fluid and I may enter the process at any point depending on patient positioning or position of pain, etc.
With the patient standing I check the single-leg squat test, and if they demonstrate abductor weakness I have them repeat with an object held overhead. The following link leads to a video in which I demonstrate this process as well as addressing the adductor tightness using the Drop Release instrument.
https://vimeo.com/433658765/be45fa38f7
With the patient in the supine position I check the relative heights of the ASIS, I check for springing across the pubic joint by contacting one ASIS and the opposite thigh roughly over the AIIS. If there is no spring one direction I set the drop piece and give a thrust the same way, rechecking afterward. I also check whether there is an excessive amount of space between the lumbar spine and the table indicative of hyperlordosis or L/S joint dysfunction.
Still in supine position I will check the location of each greater trochanter, palpating as I lift the leg as in SLR. According to Sauermann, if posterior femoral glide is adequate the trochanter will stay roughly the height off the table surface as the leg is lifted. This is due to the posterior glide of the femoral head in the acetabulum. If instead the trochanter lifts off the table with SLR, it is indicative of the “anterior femoral glide syndrome” and must be addressed. Dr. Brett Winchester demonstrates a great approach to this in chapter 8 of Dr. Liebenson’s most recent edition (page 682). Using a drop piece (or speeder board as he showed), the doc contacts the trochanter and with the patient’s knee flexed and the hip in adduction a thrust is administered A-P and M-L.
I also check the FABER and FADIR tests bilaterally. Even if negative these tests provide a good deal of information in regard to hip mobility in circumduction, posterior glide, and they can demonstrate how tight the posterior hip is by whether or not the pelvis lifts off the table with hip movement. With the patient in hook lying, I allow the knee to fall outward and assess the tightness of the hip flexors as well as the adductors, addressing any overly tight areas as I go. I also allow the knee to fall inward and check the tightness of the TFL and gluteus medius, again addressing tightness as I go.
After addressing the hip joint I run a quick alignment check of the knees and ankles. Commonly on the side of complaint I will find the tibia to be externally rotated and posteriorly shifted in relation to the femur and the opposite tibia. I check this by locating the medial and lateral edges of the patella with my headward hand and palpating the tibial tuberosity with my footward hand. Ideally the tibial tuberosity should be roughly centered beneath the patella. I also compare the heights of the femur and tibia off the table in relation to each other and compare to the opposite leg. In cases where the tibia is rotated and shifted I use a “bunny hop” adjustment in which I prestress the joint forward and toward medial rotation with my hands and gap the joint with the rapid hop.
Often in the presence of the knee alignment described I will also find a relative internal rotation of the high ankle. I do a quick check by putting the tips of my index fingers on the malleoli pointed toward each other. The line formed by the two fingers should angle upward toward the midline by a fair amount. If the line is instead close to parallel to the table I use posterior pressure on the lateral malleolus while gapping the mortise joint or applying a “whip” motion to the ankle with my hands.
After addressing all necessary areas with the patient supine, I have them lie prone. In this position I again check hip girdle function and the interplay between hip and lumbar spine movement. As I described above, I have the patient flex the knee and I use their lower leg to passively move the hip into both internal and external rotation. I observe the timing of lumbar movement, as there should be relatively little movement until end range hip rotation. Early movement is indicative of excessive hip tightness likely affecting the lumbar spine. I address tight hip rotators at this time, paying close attention to the deep external rotators.
Prone positioning also allows me to assess the patient’s hip extension pattern. Using my headward hand to palpate the lumbar extensors and gluteus medius and my footward hand to palpate the hamstrings and adductors I have the patient “keep the knee straight and lift the leg.” Hip extension should ideally be driven by the gluteus maximus but is often instead initiated by one of these others. If this is the case, I will teach the patient a simple patterning drill to work on in which they consciously flex the gluteus maximus on the side in question prior to extending the hip. I stress that it is to be two distinct actions - first tighten the glute, then lift the leg - to prevent substitution during the drill. I have them do this on each leg 15 times several times daily, alternating legs with each rep as in normal gait.
I share the above flow not to claim it is the only way to do things, but rather to demonstrate part of what I have assembled in my years of experience. I have taken bits and pieces from countless seminars, books, videos, classes, conversations and melded them into this ever-changing framework that I only roughly adhere to, as every patient is unique. However, while we understand that each patient is an individual, there are only so many ways the body can shift and still function well enough to walk in our door. I have found that addressing these kinetic chain factors helps me to feel like I’m working to the root of things, and providing corrective exercise for the patient to address them at home gets them on board. I am careful not to present my findings in a nocebo-inducing manner of “everything is wrong with me” and instead stress that their body is amazing and has adapted marvelously to solve some problem. We are just going to help it out and try to allow it to be more efficient about function.
I typically supply whatever home exercise is appropriate to support the findings, often using some resisted abduction with bands, emphasizing concentric or eccentric, standing or supine, all dependent on the patient. I also use the prone hip extension patterning mentioned above. Really, anything in your repertoire to support the function we’re after is appropriate, and I guarantee the majority reading this are better at rehab than I am.
In closing, I hope my readers can find that nugget or two that they might work into their own approach as I have with so many tidbits over the years. As long as we put the patient’s well-being first and do our best for them, punting when necessary, we are doing things the right way. I do, however, strongly encourage us all to consider the hip girdles especially and the rest of the lower kinetic chain when addressing lower body complaints, including thoracolumbar, lumbar and SI complaints. Likewise, the shoulder girdle when addressing middle and upper spinal complaints - but that’s for another article.