Monday, January 11, 2016

How to Identify Pathological Movement - Part III

Last week we looked at technologies that could be used to assess movement.  This week we will start to look at individual movements and how we can score these to objectively quantify deviations that we see.

Scoring of the Movement Assessment (MA)

Before we begin the review of each of the tests, it is important to understand the scoring system for the MA.  The scoring system is important for the purposes of quantifying the movements themselves, but also for educating the patient or athlete about his or her movement patterns and finally, for establishing a baseline against which future measurements can be compared.  The MA is scored on a 0 to 3 scale using the criteria below, but keep in mind that these are not exhaustive lists for scores of 1 and 2.  Detailed scoring by deviation is listed for each individual test in the paragraphs that follow.

 

TEST #1:  Full Squat Test (FST) – the full squat test is used to assess how an athlete moves his or her body through a full squatting motion.  This test is crucial because it lets us know about the athlete’s balance, the flexibility of their hips, knees and ankles, the mobility of the spine and hip, and strength and endurance as they move the body’s center of gravity through a full > 90 degree squatting motion for multiple repetitions.  It also provides us with crucial information about exactly where the athlete’s movement is breaking down and whether that movement is breaking down in eccentric or concentric phases.  Using this information, we can identify not only what needs to be strengthened in the kinetic chain, but how it should be strengthened (eccentrically or concentrically).  During the full squat test, the athlete is asked to perform a full squat with little instruction about the depth of the squat expected, or the foot or knee placement.  The goal is to assess how a given subject will naturally perform the movement when given the opportunity.  The verbal instruction provided is “with your feet shoulder width apart, please perform a full squat.”  The athlete is viewed from both the anterior and posterior position.  They are asked to perform 10 repetitions facing toward and 10 repetitions facing away from the observer. 

During the full squat test, you are assessing the depth of the squat to 90 degrees, whether or not the heels remain on the floor, what the knee alignment is throughout the descent and then the ascent, and whether or not there is a lateral shift in the body at any time during the motion.  You are also assessing whether or not there is any change in mechanics when multiple repetitions are performed.

Clinical Implications of Full Squat Test

There are numerous deviations that show up in athletes performing squats.  Below is a list of some of the most common deviations associated with the Full Squat Test and the associated clinical implications.

Lateral deviation – or simply shifting the weight more to one side vs. the other.  This creates a tremendous amount of imbalance in the loading of the entire system and can contribute to significant strength deficits and a subsequent decrease in power output.  In the subject pictured, you will notice that she shifts her weight to the right side by ~3.5 inches when she squats.  This greatly increases the stress to the right side of the body and can result in significant muscular imbalances between the left and right sides of the body in strength, endurance and flexibility.

Some of the factors that can contribute to this shift include limited range of motion, decreased proprioception, pain, poor quadriceps strength and poor motor planning (or just bad training habits which lead to poor motor planning).  It is important to determine if the athlete is having pain with this or any action used to assess movement by simply asking “does this movement cause you pain?” 

Suggested Corrective Exercise:  When athletes present with this type of movement pattern, one of the most important things to consider doing to improve is the “Squat Neuromuscular Retraining Exercise” or “SNMR” (which will be described in later sections).  Along with that, it is important to incorporate dynamic stretches utilizing the principles of Squat Neuromuscular Retraining (SNMR), Lumbar Hip Disassociation, and the Single Leg with Dynamic Lower Extremity Movement exercise progression.

Increased trunk flexion – or excessive flexing of the lumbar spine which results in bending forward at the waist as opposed to movement from the hip.  This results in vertical displacement of the upper body or exaggerated knee flexion.  This deviation can come in many forms and can present in many different ways.  Two of the most common signs of this type of deviation are flexing forward in the lumbar spine instead of flexing at the hip and the chest contacting the knees at the end of the squat.  Increased trunk flexion directly impacts the lumbar spine through abnormal loading of the lower back.  Over time, this increases wear and tear on the lumbar spine and also significantly impacts lower extremity strength and power gains since the lower back bears load increases associated with additional training, instead of the hips, gluteal muscle groups, the quadriceps and hamstrings and the lower legs.  When athletes present with these movement patterns, there very often tends to be difficulty in differentiating lumbar movement from hip movement.  These athletes have a difficult time discerning the difference between motion that comes from the hip versus motion that comes from the lumbar spine.  In these cases, athletes can benefit from training in “lumbar hip disassociation”.  There also needs to be a determination if the lack of movement in the hips and/or knees is the result of decreased range of motion in the knee or hip, pain or tightness.  Simply asking “does this movement cause you pain,” and checking the range of motion in the knee and hip manually can provide insight into the reasons an athlete might perform a squat in this fashion. 

Suggested Corrective Exercise:  Training in lumbar hip disassociation as well as adding dynamic stretches (specifically the sumo squat), and the Single Leg with Dynamic Lower Extremity Movement exercise progression to the training plan will aid significantly.

Limited range of motion – or inability to perform the squatting motion throughout the full range without falling can be a result of limited flexibility of the quadriceps, hamstrings, calves, hip and lumbar spine as well as decreased strength gains and power output from the lower body.  Limitations in range of motion can result from pain, poor joint mobility of the hip, lumbar spine, foot and ankle or soft tissue limitations (i.e. decreased gastrocnemius or quadriceps flexibility) and poor balance.  Limitations in range of motion can show up in a lot of ways, whether it is in decreased depth of the squat (limited knee flexion) or loss of balance during the motion.  The subject in this picture has a decrease in knee flexion angles and due to the excessive weight shift forward, he lost his balance as well. 

Suggested Corrective Exercise:  When athletes present with these movement patterns, some treatment options to consider include squat neuromuscular retraining (SNMR), dynamic stretches, manual stretching and mobilization to the limited joints or tissue. 

Heels coming off floor – or inability to perform a full squat without the heels coming off of the floor can result in limited range of the squat which limits strength gains, flexibility and power output.  Heels coming off the floor can be caused by limited range of motion of the gastrocnemius or soleus/deep posterior compartment, poor balance or limited range of motion at the foot and ankle. 

In this picture, this subject has full knee flexion but lacks flexibility of the calf muscles which limits her from getting full range of motion and causes her heels to come off the floor during the squat.  When athletes present with this type of movement pattern, some treatment considerations include determining if the lack of motion originates at the knee or ankle. 

Suggested Corrective Exercise:  The addition of dynamic stretches, including manual stretching in the routine, stretching the gastrocnemius and soleus/deep posterior compartment and using the Single Leg with Dynamic Lower Extremity Movement exercise progression can be beneficial.

Hip adduction/femoral internal rotation – or the knees coming together with descent (on the way down) or ascent can have a direct impact on how forces are absorbed through the knee, hip and low back as well as have a negative impact on strength and power output. This movement pattern can have a huge impact on the integrity of the ligaments of the knee and can put the anterior cruciate ligament at risk.  Hip adduction and femoral internal rotation can be the result of poor core stability, decreased proprioception or decreased gluteus medius strength.

Suggested Corrective Exercise:  When athletes present with these movement patterns, there needs to be a component of hip (especially gluteus medius) and other core strengthening, and the Single Leg with Dynamic Lower Extremity Movement exercise progression.

Loss of balance – or the athlete is not able to go through a full range of motion without a loss of balance, often resulting in falling backwards or falling down.  Loss of balance has a significant impact on athletic performance and the ability to generate maximal force or power and also tells you a lot about an athlete’s sense of body awareness.  Loss of balance can result from lack of dynamic or static balance, lack of stability of the core or hip, lack of range of motion at the lumbar spine, hip, knee or foot/ankle or poor training technique. 

Suggested Corrective Exercise:  These athletes benefit greatly from the addition of the SNMR, lumbar hip disassociation training, core training, gluteus medius strengthening and dynamic stretches (specifically the sumo squat).

Dr. Nessler is a practicing physical therapist with over 17 years sports medicine clinical experience and a nationally recognized expert in the area of athletic movement assessment.  He is the developer of an athletic biomechanical analysis and author of a college textbook on this subject.  He serves as the National Director of Sports Medicine for Physiotherapy Associates, is a Safety Council Member for USA Cheer National Safety Council and associate editor of the International Journal of Athletic Therapy and Training. 

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