Hip Stability

by Juliana Gildesgame PT, DPT

Do you have knee pain with stairs? A feeling that your knee might give out on you? Ever hear clicking, grinding, or popping from your knee?

While there are many reasons for knee pain, research and clinical experience consistently demonstrate that knee pain is often the result of decreased hip stability. Hip strength refers to how much force the gluteal or buttock muscles can lift when generating their maximal contraction. Hip stability relates to how often and how successfully your glutes activate when you are doing functional activities, such as walking, running or stairs.  Typically people with good hip strength have good hip stability, but this is not always the case. When you are considering training your gluteal muscles its important to think about which functional activities you would like them to work better in.

I’ve heard, “it’s all connected” but how is the hip related to the knee?

The forces at the trunk and the knee have a direct impact on the forces at the knee. The gluteal muscles control the thighbone and prevent it from moving towards the midline of the body or rotating inwards towards the body. This is an important job because when the thighbone moves towards the midline of the body, the patellar tendon causes compression at the patellofemoral joint and often results in pain. 

Notice in the picture how his knee stays in line with his ankle and does not move toward the midline of his body, and in figure 2, how his thighbone and knee move inwards—he is not using hip strategy to control his leg.

 

If the hip impacts the knee, how does the ankle play a role?

Knees are affected not only by the hip above, but by the ankle below.  When the knee collapses inwards, the foot also moves into relative pronation. Pronation gets a lot of bad press to the point that patients report that they’ve been told that they’re “pronators” with a shameful look on their face.  But to be honest, pronation is not a four letter word!  Pronation is a natural, normal part of the gait cycle where the bones of the foot organize to accept weight into the lower extremity. People who have difficulty pronating tend to have increased forces at their lower backs. Pronation occurs when the patient is not able to control their pronation or not able to transition to Supination and therefore not best able to utilize their calf muscles.  So what is the take home message with the foot?  Learn to control the arch of the foot so that your foot can accept body weight appropriately. If you don’t have strong arches, then develop some! Stretch the muscles in the front of the shins and learn to control the muscles in the calf.

What you can do to improve your hip strength and stability:

  1. Check with your physical therapist to determine whether gluteal strengthening is appropriate for you.
  2. Notice the activities that are typically painful or difficult to do because of knee pain or instability.  This will influence how you train your hip musculature.
  3. Have your hip activation assessed. If you don’t activate your gluteal muscles well, it will be nearly impossible to stabilize them.  This means that you should be able to differentiate between pinching your buttock muscles and turning them on in a functional and sustained way.

When you’ve determined its safe and appropriate to proceed, you may want to consider a few cardinal exercises:

 1. THERABAND SQUAT

Stand with your knees and feet shoulder distance apart.  Feel your hips crease as you bring weight into your heels. Use a band above your knees to remind you to press outwardly from your hips as you go down and as you come up.

2. HYDRANT

Start with your hands and elbows under your shoulders and your knees under your hips.  Lift your left thigh away from your body and slightly away from your head. You will know if you are lifting your leg in the correct position if you can feel the side of your buttock working. If bearing weight through your knee joint is problematic, consider doing this exercise in sidelying or in standing.  Check with a physical therapist at CCPT if you are unsure of your alignment to maximize your work out.

When you start to develop control of your hips, you may be surprised that your knees improve in kind. Continue to progress your hip stability training according to the activities that you would like to get back to. For example, if your knee bothers you after a long hike, you may need to work on endurance, which would mean increasing the time increment of your exercise. 

If your knee bothers you more while you run, then you may need to adjust the power of the exercise by determining how many sub maximal contractions you can do in one minute. Consult with the therapists at CCPT to determine which hip strategies are most appropriate for you to help you achieve your goals and move with ease. 

References:

  1. Nakagawa TH, Maciel CD, Serrao FV, Powers CM. Hip and knee kinematics are associated with pain and functional status in males and females with patellofemoral pain. Int J Sport Med.  2013; 34;997-1002.
  2. Souza RB1, Powers CM. Differences in hip kinematics, muscle strength, and muscle activation between subjects with and without patellofemoral pain.JOrthop Phys Ther.2009; 39: (1) 12-9.