Following our last discussion on shoulder pain, we are going to discuss the other ball-and-socket joint in our body, the hip (known as the femoroacetabular joint, as it is formed by a connection of our femur, thigh bone, and the acetabulum, a socket formed in our pelvic bone) and some of the more common reasons that we can experience hip pain. The hip just like the shoulder is designed to be a mobile joint. This is apparent from the fact that it is a ball-and-socket joint that is capable of moving in any plane or direction. Just like the shoulder, the hip forfeits some stability to allow for the freedom of movement that it requires. Obviously, the ability of our hips to move is very important to ambulation and movement.
Hip Anatomy & Function
Anatomically, the hip gains stability passively through ligamentous support and a joint capsule. There are 3 ligaments that make up a majority of the joint capsule of the hip include the iliofemoral, ischiofemoral, and pubofemoral ligament. Each of these ligaments attach from the hip to the 3 regions of our pelvic bone the ilium, ischium, and pubis. Just like we discussed the shoulder girdle, the pelvic girdle is important to proper hip function. The pelvis is responsible for connecting our spine (specifically the sacrum) to our hip and provides an anchor for the above discussed ligaments and many of the muscles that assist in stability and allow for mobility of the hip. There are a significant number of muscles that attach to the hip to create the mobility required at the hip joint.
We will review some of the primary muscles of the hip. From the front, the primary muscle of our hip is known as the iliopsoas muscle, which is the primary flexor of our hip (creates the motion the pulls our knee toward our chest). From the outside (or lateral aspect), the primary muscles include the gluteus medius and gluteus minimus. The gluteus medius is the primary abductor of our hip (moves our hip and leg away from midline) and the gluteus minimus is an external rotator of our hip. From the backside, the primary muscles include the gluteus maximus and the piriformis. The gluteus maximus is the primary extensor of the hip and is the strongest muscle of the hip. It is also very important to hip and trunk stability. The piriformis is the primary external rotator of the hip. From the inside (or medial aspect) the primary muscles are the adductor group (magnus, longus, and brevis). The adductors as their name states are the primary adductors of the hip (moves are hip and leg toward midline). There are a number of additional muscles of the hip, most of which assist with rotation of the hip joint, for simplicity purposes we will not review all of the muscles of the hip in this post.
Functional Causes of Hip Pain
So, let’s start to review some of the possible causes of functional hip pain. Just like all of the other regions that we have discussed, sitting is tough on the hips. Not just because they have to support the weight of our upper body in a seated position, but because they are placed in a flexed position with sitting. The flexed position of the hip with sitting has a couple of consequences relative to overall hip function.
First, this position causes a shortening of our hip flexor (particularly the iliopsoas) muscles. This will not immediately lead to a long-term issue, however considering the length of time that many of us are required to sit, it will have consequences over time. Shortened hip flexors can be a source of anterior (front side) hip pain. Shortened hip flexors can directly influence the position of our pelvis forcing us into a forward rotated pelvic position (known as anterior pelvic tilt) this position of the pelvis though most commonly associated with lower back pain, can have effects on the hips and lead to some functional-related hip issues. Just like we have upper cross syndrome that can affect our neck and shoulders, we can also have lower cross syndrome which can be associated with tight hip flexors and their relationship to anterior pelvic tilt.
Lower cross syndrome is associated with muscular imbalances around the hip, pelvis, and lower back. It often is correlated with prolonged sitting and a sedentary lifestyle. The muscular imbalance involves overactive, tight hip flexors (typically iliopsoas) and tight lower back extensors (known as the erector spinae) and underactive and weak abdominals and gluteals. Often, the hamstrings also become tight in this scenario relative to compensating for weakness in the gluteal muscles. From the description of lower cross syndrome, we should see some potential functional issues that could arise as a result of it. Since our abdominals, particularly the deeper layers of the abdominals (transverse abdominis and the obliques) along with the gluteals are very important to stability in our lower back, pelvis, and hips; the inhibition of these muscles will result in a negative effect on core stability. As we have previously discussed in our core stability post, the noted increase of tension and activation of our hip flexors and hamstrings can be a direct result of attempting to compensate for a lack of core stability and gluteal function, respectively. As a result, if we do not do anything to correct lower cross syndrome it can continue to perpetuate further limiting core stability and creating tension in our hips and lower back. Additionally, our gait can be altered as a result of an inability to fully extend our hips from tension in our hip flexors. Extension of our hip is important with walking and running as it is necessary to allow proper function of our gluteals, particularly the gluteus maximus, which is the primary extensor of our hip. Limited hip extension from tension in our hip flexors can further cause inhibition in our glutes. Since the glutes are very important to hip stability and are heavily involved in our body’s ability to create power it is easy to see how lower cross syndrome associated with prolonged sitting and a sedentary lifestyle can be very problematic to our hips.
In addition to causing tight hip flexors and being associated with lower cross syndrome sitting also, in and of itself, results in inhibition of our gluteal muscles as a result of reducing blood flow (known as ischemia) to our glutes. This occurs as a result of the pressure associated with sitting on our gluteals which restricts blood flow. From all that we have discussed it is obvious why sitting is not a great position for our hips (and lower back).
Moving forward, let’s look at another commonly diagnosed cause of hip pain, bursitis, particularly trochanteric bursitis. This condition is often a result of an underlying functional issue that creates a shortening or tightening of our iliotibial band (often referred to as the IT band), a band of connective tissue that extends from our hip to our knee on the outer portion of our thigh. Tension in our iliotibial band frequently results from under activation or weakness in our gluteus medius, which as discussed above is our primary hip abductor. The gluteus medius also is one of our primary lateral stabilizers of our hip (very important to allowing us to walk and run in a straight line). Without the proper ability to activate or maintain proper strength in our gluteus medius, the iliotibial band will tense to compensate for lateral stability of the hip. Tension in the iliotibial band often results in friction to the trochanteric bursa as it directly overlies this bursa on the outside of the hip. Friction to the trochanteric bursa can result in inflammation and pain of the bursa resulting in trochanteric bursitis. Again we see why we often do not want to just treat the region of pain in this case the bursitis, though this is important to alleviate the pain associated with this condition, it is just as important if not more important to treat the underlying function issue of the underactive or weak gluteus medius to decrease the stress to the trochanteric bursa to allow for long term relief and improvement.
Another commonly diagnosed condition that can cause hip pain or discomfort is piriformis syndrome. Piriformis syndrome is also commonly misdiagnosed as a disc herniation in our lower back. A very common symptom of piriformis syndrome is radiating pain into the leg, which is also very common with a disc herniation. The reason for this is that both of these conditions typically cause sciatica, as a result of compressing the sciatic nerve. As discussed above, the piriformis is a muscle on the backside of the hip, which is the primary external rotator of the hip joint. The piriformis overlies the sciatic nerve and with injury or swelling of this muscle there can be a direct compression of the sciatic nerve that results in compression or inflammation of the nerve that then results in sciatica. As a result, symptomatically piriformis syndrome typically includes deep pain in the buttock region that refers into the thigh and lower leg. Though piriformis syndrome most frequently is a result of direct injury or overuse of the piriformis muscle, it can also be associated with dysfunction in the sacroiliac joint. The sacroiliac joint is the joint that connects our lower back to our pelvis. The relationship here is that the piriformis attaches to the sacrum and will often tighten to protect the sacroiliac joint and limit motion with sacroiliac dysfunction. The tension in the piriformis that is brought on by the sacroiliac joint causes the muscle to compress the sciatic nerve and sciatica can result.
The ankle is important to discuss when we are talking about the hip joint. The relationship between ankle mobility and hip function. Ankle mobility is very important to overall hip function and particularly proper activation and use of our gluteus maximus with walking and running. This functional relationship works similar to the relationship between tight hip flexors and gluteus maximus function, in that both limit proper hip extension and activation of our gluteus maximus muscle with walking and running activity. Again, improper activation of the gluteus maximus can result in a decrease of hip stability and also increase strain to our lower back, both of which can result in increased demand to our hip joints with associated pain and structural breakdown, increasing our risk of conditions such as arthritis. The foot and ankle are also very important to proper muscular function as they function as a receptor to our brain to provide information on proper muscle activation and sequencing during walking and running. As a result, loss of ankle mobility can also increase more stress to our joints including the hip as a result of negatively affecting muscle activation and sequencing with walking and running.
We would be doing a disservice if we did not discuss the importance of core stability to the health of our hips. Just like we discussed the importance of scapular stability to shoulder health, our core is key to maintaining stability of our lower back and pelvis. The pelvis provides the socket (known as the acetabulum) for the ball of our hip (known as the femoral head, a portion of our femur) The ability to maintain a stable pelvis through good core stability is important to maintain good positioning of the femoral head in the acetabulum and also allow for proper muscular function around the hip joint. Without good core stability allowing for better pelvic stability, we are at a risk of displacing more stress to our hip joint, which can ultimately increase structural breakdown of the joint leading to pain, inflammation, and arthritis. In addition, as we discussed previously, the loss of core stability can directly result in increased tension in our hip flexor (iliopsoas) and hamstring muscles, which also increases strain and restricts mobility of our hip joints. Therefore, one of the keys to unlocking and improving hip function and mobility is good core stability.
Other Factors that need considered with Hip Pain
As always, hip pain and injury can result from trauma, which unfortunately we can never truly prepare for or prevent. Just like, we can maintain our vehicles as best we can with oil changes, good brakes, tires, etc.; we can still get into collisions that damage our well-maintained vehicles. However, as discussed above there are many things that we can do to help improve overall hip health and reduce our risk of non-traumatic hip pain and musculoskeletal causes of hip injuries. These types of hip injuries often require medical attention and should be assessed and treated appropriately, often with pain management, conservative options (chiropractic, physical therapy), and in some cases surgery. The full spectrum of hip injuries associated with trauma include sprains, strains, bone bruises, labral tears, dislocations, and fractures are beyond the scope of this post. However, they are certainly sources of hip pain that require attention and therapy. Our discussion today is focusing on the everyday mechanical stresses that we can modify to help reduce strain on our hips and decrease our risk of hip pain.
Just like we discussed in our last post on shoulder pain, regarding referred pain from the neck causing shoulder pain. Hip pain can be a result of pain referred from the lower back. The lower back commonly refers pain into the region of our hips, especially into the buttock region or backside of our hip. Another common region of the body that can refer pain into the hip is the knee and vice versa, as hip pathology or injury can refer pain to the knee.
Treatment Options for Hip Pain
As with the other regions of the body we have discussed, the best treatment approach for hip pain is to first discover what is causing or contributing to the painful hip. This is done through a thorough evaluation that not only assesses the area where pain is presenting, in this case the hip, but also areas that could contribute to hip pain. Since hip pain has many factors that could be causing more stress to the hip, some of which we have discussed, we need to assess the whole body to discover the underlying issues that are displacing more stress to the hip. Once determined we are ready to devise a treatment plan with a focus on long-term change by correcting the underlying deficiencies to reduce strain to the hip and allowing it to function as intended.
Obviously improving posture with sitting is an important component of helping to reduce or correct mechanical hip pain. Mechanical therapy in the form of stretching, massage, and mobilization-based techniques (chiropractic, physical therapy) can have a profound impact on helping to reduce muscular tension and improve overall joint health and mobility. Additionally, improving core stability to assist with improved pelvic stability helps reduce stress on our hips. Good core stability also helps to decrease the risk of compensatory tension of the hip flexors and hamstrings that can negatively affect the health of our hips.
The primary things that we need to be mindful to help maintain good hip function and health, include:
- Hip mobility
- Glute muscle function
- Ankle mobility
- Core stability
We hope that this post has made you more aware of some of the common factors that can cause hip pain. There is certainly a need for all of the treatment options that we have today from the most conservative to the most invasive, however determining what the best option is for the individual by way of understanding what the causative factors of their hip pain are and not just treating them from a symptomatic standpoint is the key to having better and more positive outcomes. Along with reducing the potential for future recurrencies.
…Till Next Time
