Month: June 2014

Gluteus Medius: the Root of Chronic Leg Pain?

Dealing with knee pain while running? Or even shin splints? What about a history of lateral ankle sprains? These may all be a symptom of a weakness at the hip, specifically weakness of the Gluteus Medius. We have all heard of the Gluteal Muscles but may not have heard of the Medius. The Gluteus Maximus gets all the glory for making a nice back side but the Medius may have greater implications in the the health of the lower extremity.

Anatomy and Function

The GMedius originates on the posterior aspect of the Ilium or the top part of the pelvis. The tendon inserts into the lateral surface of the greater trochanter of the femur, or the bony part of the hip on the side of the hip.

The Gmedius’ primary function is abduction of the hip or moving the leg away from the midline of the body. It also contributes to most of the actions of the hip but for the sake of this topic we will focus primarily on abduction. The Gmedius is also responsible for preventing the opposite side of the pelvis from dipping down while in the stance phase on that side. This helps prevent the Trendelenburg Gait which is pictured below.

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By creating stability in the frontal plane at the hip, it also creates stability in the same plane for the knee and even down into the foot. By limiting the amount of valgus moments at the knee during functional movement, pronation of the foot is also limited. Some individual difference can occur as we are all shaped different but we can hopefully prevent overpronation of the foot by controlling the knee through the hip. Below is a picture to visually explain what occurs when a valgus moment occurs in the knee.

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Pathologies
IT Band Syndrome
The primary cause of IT Bandy Syndrome is due to decreased abduction of the thigh and external rotational of the thigh while running. This creates and increased tension of the IT Band which runs along the lateral side of the thigh. This increased tension will create areas of friction either at the greater trochanter or the lateral femoral condyle of the knee. With soft tissue work of the IT Band (foam rolling or massage), and strengthening of the hip, there should be a decrease in pain with the IT Band
Patellofemoral Pain Sydrome
Patellofemoral pain syndrome is used to describe injuries such as patellar tendinitis and patellar chondromalacia (wearing away of the cartilage under the knee cap). Much like the IT band, these chronic injuries are caused by the decreased thigh abduction and external rotation. The lack of frontal plane stability at the knee caused by a weak GMedius can lead to poor patellar tracking mechanics through the femoral groove. The increased valgus angle at the knee also does not allow the quadriceps to work at efficiently as possible. This poor angle places more stress on the patellar tendon with high loads. This, if not corrected will lead to patellar tendinitis.
ACL Sprains
Probably the most known athletic injury is the ACL injury. It can lead to surgery and 6-9 months of intensive rehabilitation. The noncontact ACL injury can be prevented with a strong Gmedius. One of the mechanisms of tearing an ACL is rotation at the knee. The control of adduction and internal rotation of the knee through the GMedius can help protect the ACL in activities such as cuting and landing. Proper cutting and landing is important but a strong Gmedius will allow the body to absorb higher loads without a collapse of proper mechanics.

Assessment

For a quick and functional assessment my go-to test is the single-leg squat. This test places us in a position where we must have great control of the pelvis and knee to complete correctly. I first allow the patient to do it without any instruction other than visually how to do the exercise. The keys to visually assess are the amount of valgus angle at the knee. I also am looking at the hip and foot. If the arch collapses immediately or the knee angle gets better with some sort of support at the arch, then the issue may be more at the foot and ankle. But if the arch is compensating due to the lack of control at the knee then the hip will be the issue. I like to video my athletes while doing this so they can see the dysfunctions that are occurring. After I have seen how they are moving without any cues, I like to teach them a few cues so they can feel how to move correctly. My main cue is to keep the patella over the second toe. This cue seems to be the biggest help.

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Strengthening

I have a couple go-to exercises that I use for strengthening of the GMedius. While the patient or athlete is still symptomatic or non-weight bearing the clam exercise and the sidelying hip abduction exercise have been an essential part of my rehabilitation. These can be advanced through bands or weights. An important note with my sidelying hip abduction exercise is I had a bit of hip extension. This has lead to a greater focus on the GMedius and a greater burn when my athletes are doing it. It is also important to maintain a neutral spine while doing these exercises as it can lead to compensations.

As the athlete becomes more functional I like to progress to exercises that put them on their feet. The miniband side shuffle is one I rely on often and have found great results with. The Stepdown exercise is also a staple with the emphasis being on the eccentric phase of the exercise. I also like to implement the miniband around the knees with exercises like hip bridges and squats as it puts a load on the hip abductors while performing other functional exercises.

Clinicians, what other assessments are you using for general glute weakness or Gluteus Medius specifically? What exercises are you using to strengthen the Glute Med?