Human movement is inherently complex. We have already discussed how we can attempt to simplify human movement by breaking it down into the phases of absorption and propulsion. During these phases, multiple segments of the human body are required to coordinate with one another in order to produce meaningful movement patterns, whether that be walking, running, squatting, jumping… the list goes on. These synchronized movements, however, occur at a speed that is hard for the human eye to fully appreciate and comprehend. It is difficult to watch someone run and be able to tell where an individual lacks mobility or motor control, so today I will attempt to illustrate an alternative way to create a movement diagnosis that still allows us to find segmental dysfunctions while respecting the whole that is human movement.
In order to create a movement diagnosis, we will look at fundamental patterns that are further broken down into their respective parts. While we are assessing these patterns, we will ask ourselves three questions along the way:
· What should it look like?
· What does it look like?
· Why?
Fundamental Patterns
When we begin to assess human movement, we start with fundamental patterns. Fundamental patterns are comprised of movements performed in a full weight bearing position that require multiple segments to coordinate with one another simultaneously. This allows us to appreciate the whole. The overhead deep squat, hurdle step, and in-line lunge, as are used during the Functional Movement Screen, are all examples of fundamental patterns.
The specific fundamental patterns chosen during the process of creating a movement diagnosis are less important than your ability to understand what each fundamental movement is comprised of at a segmental level. The ability to perform a movement analysis will enable you to understand why a specific movement doesn’t look the way it should.
The toe touch is another example of a fundamental pattern. To better illustrate this concept, let’s examine the toe touch and break it down into its respective parts.
Toe Touch (Multi-Segmental Flexion)
What should it look like?
· Touch toes with knees remaining extended
· Posterior weight shift
· Uniform spinal curve
What does it look like?
· Unable to touch toes with knee extended
· Adequate posterior weight shift
· Flat lumbar spine; hinging at mid-thoracic spine
Fundamental Pattern Components
As you can tell, we must be very particular about the movement quality that is expressed when examining fundamental patterns. Humans are incredible compensators and, by being picky, we are able to better identify when compensations occur. Diana’s toe touch was not ‘ideal.’ “Why?”
Performing an ideal toe touch requires that the individual demonstrates adequate hamstring length, hip flexion, and spinal flexion. Inadequacy in any of these domains results in a less than ideal outcome. We will now examine these individual parts to better understand why compensation has occurred.
Active Straight Leg Raise
What should it look like?
· 70 degrees of hip flexion
What does it look like?
· About 55 degrees of hip flexion
Passive Straight Leg Raise
What should it look like?
· 80 degrees of hip flexion
What does it look like?
· About 90 degrees of hip flexion
Double Knees to Chest
What should it look like?
· 120 degrees of hip flexion (thighs against the rib cage)
What does it look like?
· Thighs against the rib cage
Quadruped Rocking
What should it look like?
· Uniform spinal curve
What does it look like?
· Flat lumbar spine; hinging at mid-thoracic spine
· Subjective complaints of stiffness at lumbar paraspinals
Tissue Compliance, Joint Dynamics, and Neuromuscular Control
When we broke the toe touch down into its respective parts, there were two tests that did not meet the criteria we were looking for: the active straight leg raise and quadruped rocking. Once again, we must ask ourselves, “Why?”
There are three possible reasons why an individual could lack motion at a specific segment. The first one we will explore is neuromuscular control. Neuromuscular control refers the amount of available passive range of motion an individual is able to actively tap into. As we saw, Diana’s passive straight leg raise was about 35 degrees further than her active straight leg raise. This is an example of a neuromuscular control problem. She has 90 degrees of motion available to her but she is only able to access about 55 degrees of it. In Diana’s case, this was due to a lack of core stability. Diana was unable to create proximal stability in order to create a stable base for her lower extremity to work from. Neuromuscular control problems can also be attributed to decreased strength in certain instances.
But what if an individual is lacking motion passively? There are two possible reasons for this happening: tissue compliance and joint dynamics. Diana was also unable to meet the criteria for quadruped rocking as she subjectively complained of stiffness in the lumbar paraspinals. This subjective complaint leads us to believe that her lack of mobility during quadruped rocking was caused by a tissue compliance problem, or the muscles being unwilling to lengthen.
Let’s use a hypothetical situation to illustrate what a joint dynamics problem may look like. Imagine Diana had lacked hip flexion while performing the double knees to chest test. Let’s also pretend she complained of pinching in the front of her hip while performing the test. This would be an example of a joint dynamics problem. The femur does not glide posteriorly sufficiently enough to create room at the front of the capsule for adequate hip flexion to occur - the arthrokinematics are less than ideal.
Wrapping Up
Diana was unable to perform an ‘ideal’ toe touch. The cause for this appears to be due to a lack of core stability, as was demonstrated by the neuromuscular control problem identified while performing the active straight leg raise, as well as a tissue compliance problem while attempting to flex the spine, which was shown during quadruped rocking.
Being able to a perform an ‘ideal’ toe touch may not make you a better athlete, but that does not mean there is no value in the test. Using fundamental patterns, such as a toe touch, can help us to identify when compensation is occurring. In addition, the toe touch requires a lot of the same movement patterns that we observe during absorption, or flexion-rotation patterns. Therefore, we can hypothesize that correcting the toe touch may improve efficiency during the absorption phase, which in turn could improve performance as well as mitigate injury risk.