A squat conjures up images of large muscles bulging in sawdust-covered gyms. Deadlifts, barbells, Romanian and Bulgarian versions, snatch, thrusts, Olympic, single-leg and kettlebell variations are all welcome here. This squatting vision also welcomes athletes like my rowing friends, who sit to perform their series of squats while trying to stay dry. Many athletes must understand this movement pattern to ensure optimal transfer of large amounts of force through their system. However, understanding the squat isn’t an elitist pursuit of an extreme movement found only in gyms and sports. The squat is a movement pattern as common to the builder, picker, and reacher as it is to those of you who sat down to read this article. Sitting down is, at least, part of this action. It is this small, everyday version of the squat we are about to explore.
Our quest in this article is to explore and explain this humble and common movement pattern, the squat, and so improve our fundamental skill of clinical questioning as we gather information and solve problems.
As a practitioner, I am interested in movement patterns because they help explain why you might come into my clinic. For example, as you lower yourself into the chair, the squat-like action can cause a slight twist in your pelvis. That explains the counter-rotated mid-thorax, which then creates a secondary counter – the cranial torsion that twists the cerebellum, shortens the tentorium, and twists the neural dural system, which in turn twists the sacrum, resulting in that all-too-common ache in your lower back.
It is traditional to consider each anatomical part before considering the beauty that is the whole system. Here, we aim to see these elements from a relative, systems-oriented viewpoint. Considering the whole structure and the process or context, which is movement. As movement changes, it changes the appearance of surface phenomena that temporarily unfold from an underlying implicit order we aim to assess. This indicates the Born to Move style: a circular, reflective method of assessment.
The concept of tensegrity has taught us much, not least, that we can start our exploration from any point. But we have to start somewhere, so let us begin by taking a look at your own, or your client’s, feet during a squat. Watch as they fan and fold during a variety of movements to show us, the observer, their order. The ripple of the surface belies the underlying construct of a reality all successful practitioners must accurately assess.
For a successful squat into a chair, your client needs to go into dorsiflexion and pronation. With an adaptable system, this action will spread, open, or fan the foot. This loads the spring ligament (a ligament deep in the foot), along with other springy ligaments and myofascia that work together to distribute and absorb this shift in weight distribution. Then, as a wonderful demonstration of our evolutionarily advantageous ability to recycle potential energy back into kinetic energy, our feet spring back up to return to standing and know it for the first time.
All too often, however, we humans lose our advantage (in a variety of ways). Starting as we might in an already dorsiflexed position. Perhaps your client stands with an anteriorly shifted pelvis and an anteriorly tilted tibia, creating dorsiflexion and reducing their potential (energy) by lengthening and diluting their springy capacity. Ask this client to go into a squat, and you are asking them to go even further into dorsiflexion, demanding greater adaptability. It’s an unfair test; at least it’s unfair when compared to someone who starts in a more neutral position.
On the way down, this small squat triggers an intricate flow of movements from the 26 bones of the foot, which we label pronation. Pronation: a complex pattern of movement simplified into one word. It is too complex for this text or useful for most clinicians in their everyday work. However, it is important to realise that the calcaneus and talus should both medially tilt. The whole foot should widen like an opening fan around the axis of the second ray. This pronated foot is in an open-packed position of adaptability and mobility.
Reverse this as they come up out of the squat, and we have the complexity of supination. Remember that the calcaneus and talus are drawn back up to their hopefully neutral starting point. The whole foot narrows or folds around the same axis, the second ray, returning to its closed-packed position of stability and strength.
It would be unfair to assess the position of the tibia and fibula without considering the position of the talus. The talus can be imagined as the tenon that sits in the mortise created by the tibia and fibula (mortise and tenon are terms any good woodworker would recognise). What would happen then if the talus is tilted in the frontal plane?
A cowboy’s legs mould around his horse on long days in the saddle, resulting in the characteristic bow-leggedness, or genu varum. The laterally tilted tibia and fibula, however, tell us nothing of the relative tilt of the talus beneath.
If the talus is in a tilted position, then dorsiflexion and plantar flexion are likely to be limited, and a jamming sensation is often reported by our clients.
The simplest way to assess the talus is to use a light pinch grip to palpate this bone. Once you know the position of this bone, ask for a small squat. It may feel like the talus is drawn posteriorly, even though what is actually occurring is the tibia and fibula tilting anteriorly over the talus.
The literature on palpation (for example: Lewis and Liebenson 1993) tells us that for accurate palpation the fingers need a reference point. A pinch grip enables the finger to use or ‘find’ the thumb as its reference point. To build on this idea, we should consider the talus in relation to its closest structures. So, we move from the talocural relationship to the subtalar joint. The subtalar joint describes the relationship of the talus to the calcaneus.
From behind, the position of the calcaneus in the frontal plane is usually easy to observe. The bone itself might clearly look tilted, or you may note the Achilles tendon suddenly doglegs at an angle rather than maintaining its correct vertical alignment.
A flexible model of the foot, rather than solid, wired-together versions, is useful here to see and feel the variations. In standing, consider the implications of the talus that is tilted laterally relative to the neutral calcaneus. Or the calcaneus tilted medially relative to the neutral talus? Or the talus is tilted laterally relative to the medially tilted calcaneus? Or the talus is tilted medially relative to the laterally tilted calcaneus? In each of these variations, the subtalar joint starts in a suboptimal position. With implications for the squat and many other movements. And I still have not yet covered all the various possibilities. Three still remain: the calcaneus and talus are both neutral relative to each other; they could both tilt medially; or, lastly, both tilt laterally. These last three tell us to look again at the talocrural joint. While the relationship between the talus and calcaneus is neutral, the relationship between the tibia, fibula, and talus in these final three examples is sub-optimal.
Other texts explain the flexed, extended, hyperextended, valgus, varus, internal, and external rotated starting position of the interrelationship of tibia and femur, better known as the knee. Instead, let us turn to a movement pattern more closely related to the squat. In 1978, Goodfellow described the screw-home mechanics of the knee. The focus here is on the very start of the squatting action. Consider then the first 15% of knee flexion when the tibia should medially rotate, relative to the femur. In the final 15% of extension to return to standing, the tibia should laterally rotate relative to the femur. This describes the normal biomechanics expected during this mini squat.
All too often, in my clinic at least, I find the opposite. It is common to find a reverse screw-home mechanism. Lightly palpate the tibia and around the femoral condyles as your client performs this mini squat. If, for example, during the first 15% of knee flexion the tibia fails to go into medial rotation, ask yourself why. An answer may well present itself when we consider that for the tibia to medially rotate, the talus must medially tilt, and the calcaneus and, so, the foot to pronate. A reverse screw action often, but not always, tells us something about the foot. Now is the time to remind yourself of the action of your client’s talus now that we have developed the context.
We shall leave Kapandji’s ‘joint of pure spin’ (1987) or hip for another time and move to the pelvic girdle as we continue to understand the everyday squat.
The fundamental movement pattern of the pelvis during the squat is simple to describe, or should be. Optimal biomechanics tell us that nothing should happen in the transverse and frontal planes; the pelvis should remain neutral. In the sagittal plane, the pelvis needs to tilt anteriorly relative to the femur. The femur tilts posteriorly during the squat. This, I hope, is straightforward, so long as one starts and remains in neutral. Complexity arises when we consider some of the sub-optimal possibilities.
Much has been written on pelvic neutral in the sagittal plane but less in the transverse plane, so let us try and readdress the balance here on these pages.
Stand up and find your own, or – if you have a willing friend – their anterior superior iliac spine (ASIS). Place a finger on the right and left of this easy-to-find point on the anterior surface of the pelvis. Feel or look down to see whether one finger is anterior to the other. For example, you might find that the right ASIS is anterior compared to the left. We would call this a left-rotated pelvis. However, it is unlikely that the whole pelvis is in a pure rotation, like a basketball spinning on a finger. More than likely you found a pelvic torsion, which we shall soon explain. If you did not find this, then you are in neutral. If your friend has a neutral pelvis, they are still useful. (Don’t go breaking a friendship over a boring pelvis!) Instead, ask this neutral pelvis to turn or twist to the right and left, keeping feet planted on the ground. While you palpate the changing position of their ASISs accordingly.
Now move your inquisitive hands to the iliac crest. If you found a right-rotated pelvis, you’ll feel that the right innominate is posteriorly tilted and the left innominate is anteriorly tilted. This is normal biomechanics and is termed pelvic torsion in the literature. Normal for is when turning to the right or left, but clearly sub-optimal for starting or during a squat.
Ideally, we all stand in neutral with a slightly nutated sacrum. If nutation and counter-nutation are novel terms for you, it’s time for Google. Nutation describes the sacrum’s relative position in a closed-packed, self-locked position of strength for the sacral iliac joint (SIJ). This closed-packed position of the SIJ is akin to the explanation given of supinated feet. A right torsion tells us that the sacrum should also be right rotated. Relative to the innominates, one is anteriorly tilted and one posteriorly tilted; the sacrum on the right and left are both in relative nutation. This describes the normal biomechanics of pelvic torsion, including sacral positioning.
A sub-optimal SIJ is in an open-packed position or counter-nutated. While the pelvis may have rotated right, the sacrum has remained in the same position. This weakens the entire pelvic structure, making it non-optimal in standing and the ensuing squat. Standing in this open-packed position requires more work from the soft tissues to hold these poorly aligned bones stable (force closure). Rather than utilising the closed-packed optimal alignment of the bones (form closure) coupled with force closure. And, yes, if you’re wondering, during our workshops we teach a clinically relevant way to assess all this and more.
The implications for failing to observe your client’s pelvic position for the squat are significant. If your client stands with an unlocked SIJ, other test findings can be misinterpreted. If you fail to assess the SIJ in standing and during a squat test or stork test, you might incorrectly decide the SIJ isn’t unlocking. Why? Because the SIJ is already unlocked and simply cannot unlock further. In this scenario, you are now treating someone as though they have optimal biomechanics when the keystone of their human architecture, the sacrum, is actually in a sub-optimal position. This has implications that spiral down to the knees and feet, as we have already discussed, and also upward toward the cranium.
Implications continue North of the pelvis, and for this we consider the seminal work of MacIntosh and Bogduck (1991). These brilliantly detailed dissections show us that some of the controllers of pelvic and sacral position are anchored to the mobile ribs. An interestingly unstable anchorage. For example, the iliocostalis attaches to the innominate. When overactive, this muscle tends to anteriorly tilt the innominate, a culprit for pelvic torsion. Whereas the longissimus can nutate the sacrum, increasing force closure. This might sound like a good thing until we realise this nutation tends to be at end range, compressing the lower lumbars and pelvis and contributing to lower back and pelvic girdle pain. This suggests that an overactive longissimus would never be involved in an unlocked SIJ, but this is not the case. Consider, for example, an overactive tensor fascia latae (TFL) that might cause an anterior tilt of the innominate. The longissimus in this example is reacting to the main actor, the TFL. We need to be able to differentiate between actor and reactor in this and indeed in all movement patterns. We’ll spend time developing this skill during our next workshop together.
Let us consider then the whole pattern of a squat as we twist to sit in the expensive bucket seats of low vehicles as they race us away from a midlife crisis. Or the rugby player who needs the efficient transfer of force through an optimally aligned series of joints to jump during a line-out. Or the waiter with reverse screw mechanics in the knee, which consequently demands more work of his aching feet and makes the unlocked SIJ vulnerable, which, via the erector spinae, contributes to the tingling in his mid back.
The squat is a simple movement pattern common to us all and a wonderful opportunity for the investigative practitioner to explore through this complex system. Curious, we find areas of interest and sub-optimal biomechanics, ask next-level questions, assess clinical relevance, and take steps toward predicting the implications of your manual and movement interventions. This fundamental knowledge and practical skills are necessary to assess any movement pattern, including the humble squat.
In the next issue, we continue exploring common movement patterns as a catalyst for improving fundamental skills for every practitioner. For more information, online courses and to find your next workshop, visit borntomove.com
