Lateral hip pain (pain on the side of the hip) is routinely seen in practices across a wide range of individuals, of varying fitness levels. Lateral hip pain can range from being frustratingly annoying when exercising, to debilitating affecting sleep and simple everyday tasks like walking, going up and down stairs. But before we discuss why we get lateral hip pain; it is best to first understand the anatomy.
The hip/glute area of the body consists of a variety of muscles designed to help keep the pelvis level in addition to moving the hip joints. The important muscles in this discussion are the gluteus maximus, which is a strong powerful hip extensor muscle designed to help with forward propulsion; the fan shaped glute medius and minimus muscles which act as hip abductors (moving the thigh away from the body) and play a pivotal role in keeping the pelvis and hip joint level during single limb loading, as well as helping to absorb impact (ground reaction forces) in the early stance phase of walking/running. Finally, there is the piriformis muscle which externally rotates the thigh and also helps to abduct the thigh when the hip is bent 90 degrees, such as sitting. These 4 muscles arise off the pelvic bones and insert into the thigh bone (femur). To help reduce the friction rub between the insertion of the glute medius and minimus tendons into the thigh bone, there is a small pouch of fluid called a “bursa”. Many people will be familiar with a bursa, as when it becomes inflamed it is called a “bursitis” and can be extremely painful.
Common Causes of Lateral Hip Pain
The most common reasons for lateral hip pain are gluteal (medius and/or minimus) tendinopathy with or without a bursitis and gluteal (medius and/or minimus) partial tears, full tears can occur but are not as common as tendinopathy and partial tears. It is uncommon to have a bursitis alone, unless there has been a direct impact to the bursa, such as hitting the corner of a table.
In the case of tendinopathies, it is well documented that these are most likely to occur as a result of increased loading of the tendon. Tendons have a natural cycle they work through where they are loaded through exercise, which results in microtrauma and tissue breakdown, during appropriate rest the tissue remodels and adapts to get stronger and then the tendon can be loaded again. If this cycle remains harmonious, the tendon will get stronger and tolerate more load. However, if the load increases too quickly and/or there isn’t an appropriate rest period for the remodelling to occur, the tendon breaks down and continues to breakdown resulting in a painful tendon known as a tendinopathy. Routinely, lateral hip pain is seen in runners, especially those new to running; who have had an extended break from running; those trying to quickly increase their miles for an upcoming event. In all cases there is an increase in load which disrupts the tendon adaptation process.
Furthermore, biomechanical imbalances can play a role even if load rates remain stable. There is evidence to suggest that hip adduction excursion, (where weak hip abductors muscles allow the hip/thigh to move across the body) are associated with hip and knee pain in runners. EMG studies which investigate how muscles fire, when they fire and how strongly they fire show that in runner and walkers with hip pain there are altered activation amplitudes and firing times. In short, if a walker/runner has knee or hip pain it will alter their glute medius muscle function, additionally if the glute medius is weak (deconditioned) before commencing training or there has been a prior hip/lower limb injury that has not been rehabilitated correctly it will result in abnormal loading and potential increased loading of the glute medius/minumus tendons potentially pushing those tendons down the tendinopathy pathway. The end stage of chronic overloading to a tendon results in a degenerative tendon including partial tendon tears.
How to Treat Lateral Hip Pain
Traditionally, lateral hip pain has been treated with ice, anti inflammatories and cortisone injections (CSI) in addition to some simple exercise therapy. However, it is now known that very little inflammation is seen in tendinopathy and what is seen is mostly a result of the breaking down of the tendon structure. Therefore, traditional means for reducing inflammation are going to be of limited to little use, unless there is an inflamed bursa. Platelet-Rich-Plasma (PRP) injections have shown some benefit in recalcitrant cases of gluteal tendinopathy with improvements noted up to 24 months in 40 to 60 year olds and offer an alternative to CSI who’s benefits appear to peak at 6 weeks post injection.
In terms of exercise therapy, strengthening the glute medius and minimus muscles are vitally important with exercises that target the different fibre orientations of the muscle with high muscle activation; exercise that do this include, hip hikes, isometric standing hip abduction, single leg bridge, lateral step-up, side lying leg raises, single leg squats. Interestingly clams, a staple of many gluteal strengthening programs only shows low activation and are best used in the early phase of any rehabilitation program. For runners, increasing your cadence or step rate by 10% can help to reduce ground reaction forces and is associated with early firing of the glute medius/minimus muscle aiding in muscle firing retraining.