Injury & Rehab:
how tight hips can cause knee pain
Justin Price explains how a simple musculoskeletal assessment for the hips, and subsequent corrective exercises, can help remedy clients’ knee pain while also improving function.
Health and fitness professionals regularly see clients that complain of knee pain before, during, and after engaging in activities like walking and running. As active individuals ourselves, fitness professionals can also suffer from both acute and chronic pains in our knees after these activities. The good news is that by using a simple musculoskeletal assessment for the hips, and corrective exercises to address any identified imbalances, we can help both our clients and ourselves feel and function better.
A quick look at the parts
Anyone who has knee pain knows exactly which activities they can and can’t do without exacerbating their problem. For some people walking can be a trigger, while for others it might require something more dynamic like running. To understand why these seemingly simple and natural actions may cause knee pain, you first need to appreciate how the parts of the body should move when engaging in these activities.
When you are walking or running, you transfer weight from side-to-side as you step forward with alternating feet. Part of this weight transfer is possible because the feet have the capability to roll inward toward each other (i.e. pronate). When the foot pronates, the ankle rolls in with it, which in turn helps rotate the lower leg, knee and thigh toward the midline of the body. Simply put, the mobility of the foot and ankle enables the tibia and fibula (i.e. shin bones) to rotate inward. The femur (i.e. thigh bone), which fits into the pelvis to form the hip socket, should also rotate inward in time with the lower leg when the foot pronates.
How do the parts affect the whole?
So how can hip immobility cause knee pain? As you now know, pronation of the foot enables the ankle, lower leg and upper leg to roll inward. If the hip lacks the mobility to turn inward, however, a tug-of-war ensues between the foot – which wants to turn the ankle and lower leg inward – and the upper leg (connected to the hip socket) which is not able to come along for the ride. The joint that bears the brunt of these opposing forces is the knee, since it connects the upper and lower leg and cannot move in two directions at once. This stress to the knee can lead to pain and dysfunction.
A primary cause of hip immobility is extended periods of sitting. Whether at a computer, driving, eating, playing video games and/or watching TV, prolonged sitting places the hip sockets in a constantly flexed position. Over time, this can lead to movement restrictions in the hip socket. Overdoing athletic movements that require only one or two ranges of motion for the hips, like bike riding or running, can also lead to myofascial restrictions and subsequent hip immobility. This immobility of the hips can be a major contributor to knee pain.
Fix the part to mend the whole
Assessing hip mobility, specifically the ability of the hip to rotate inward, is a relatively straightforward process.
- Instruct your client to lie on the floor on a mat.
- Ask them to open their feet about 45 to 60cm apart and try to turn both of their legs inward so their feet move toward each other (photo 1).
- Look to see if one leg cannot turn as far in as the other leg.
- If a problem is not visible, ask your client to tell you if they feel a difference between the sides and/or if one side feels more difficult for them to turn in (both legs should be able to turn in about 30°).
In the example below, the client has almost an acceptable range of motion for her left leg, while her right leg is severely lacking the mobility to rotate inward.
Lying hip mobility assessment
If your client lacks mobility in either, or both, of their hips, this may be the cause of their knee pain (as well as other issues). Therefore, the first and most important goal is to release tension from the larger muscles that help control hip function. There are many corrective exercises you can teach clients to improve hip mobility, but the best strategy is to use self-myofascial release (SMR) techniques. The following three simple SMR exercises can greatly improve the function and mobility of the hips. Performing these exercises on a regular basis will help your client’s knees (and the rest of their body) feel and function better.
Tennis ball on butt
The gluteus maximus muscle helps control rotation of the leg and the hip socket. Using a tennis ball to release and rejuvenate this muscle (and the other smaller hip rotator muscles of this area) will enable the leg to rotate more freely in the hip socket and take stress and strain off the knees.
Use a tennis ball to release and rejuvenate the gluteus maximus muscle
Instruct your client to lie on the floor with their knees bent and place a tennis ball under one side of their butt (photo 2). Coach them to move around on the tennis ball to find a sore spot, stay there for 10 to 20 seconds as the tension releases, and then move to a new spot. Perform at least once a day for two to three minutes on each side.
Tennis ball on hip flexors
The hip flexor muscles originate on the lumbar spine, cross the pelvis and attach to the top of the leg. They also help control rotation of the leg and hip socket. Performing the following SMR technique with a tennis ball is an effective way to increase hip mobility and reduce knee pain.
Use a tennis ball to perform self-myofascial release on the hip flexor muscles
Instruct your client to lie face down and place a tennis ball under the front of their hip/leg and find a sore spot
(photo 3). Coach them to maintain pressure on the sore spot for 10 to 20 seconds until the sensation lessens, and then move the ball up and onto their abdominal region, releasing sore spots along the way from the top of the hip to just beside their bellybutton. Perform once a day for one to two minutes on each side.
Note: do not place the tennis ball on the sensitive areas just to the side of the pubic bone where the leg meets the groin.
Foam roller on side and front of leg
There are two other important structures on the upper leg that help control rotation of the hip and leg. The iliotibial band connects the gluteal muscles to the lower leg, and the rectus femoris, which is a quadriceps muscle, originates on the pelvis and connects to the kneecap. These structures must be healthy and flexible to enable the hip and knee to work correctly.
Use a foam roller to work on the iliotibial band and rectus femoris
Instruct your client to lie over a foam roller placed perpendicular to their upper leg. Ask them to roll their body to the side so the front and outside of their upper leg make contact with the roller (photo 4). Coach them to roll on any sore spots they find. Perform once a day for one to two minutes on each leg.
Note: if the pressure of the foam roller is too much for your client, they can regress this exercise by placing a tennis ball under the side and front of their leg while they are lying down.
Many of the largest and most powerful muscles of the body cross the hips and attach to the leg. Restrictions in these muscles affect the ability of the hips to function correctly and, subsequently, the amount of stress experienced by the knees. The simple hip mobility assessment and effective corrective exercise strategies outlined here can help both you and your clients experience substantially less knee pain as well as improved performance.
American Council on Exercise. 2010. ACE Personal Trainer Manual (Fourth Edition). American Council on Exercise.
Golding, L.A. & Golding, S.M. 2003. Fitness Professional’s Guide to Musculoskeletal Anatomy and Human Movement. Monterey, CA: Healthy Learning.
Gray, H. 1995. Gray’s Anatomy. New York: Barnes & Noble Books.
Kendall, F.P. et al. 2005. Muscles: Testing and Function with Posture and Pain (5th ed.). Baltimore, MD.: Lippincott Williams & Wilkins.
Price, J. & Bratcher, M. 2010. The BioMechanics Method Corrective Exercise Educational Program. The BioMechanics Press.
Rolf, I. P. 1989. Rolfing: Reestablishing the Natural Alignment and Structural Integration of the Human Body for Vitality and Well-Being (revised edition). Rochester, VT: Healing Arts Press.
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Justin Price, MA
Justin is the creator of The BioMechanics Method® which provides corrective exercise education for health and fitness professionals. He is also an expert on corrective exercise for The American Council on Exercise, PTontheNet, PTA Global, TRX, BOSU and the National Strength and Conditioning Association. For more information on the Corrective Exercise Trainer certification powered by Network click HERE.