This is part two of my detailed articles about two confusing muscles of the hip that many people blame for chronic pain with either back or hip problems, when in reality these muscles are merely reacting to dysfunction created elsewhere and trying to improve stability. The two muscles I am referring to are the quadratus lumborum which I discussed in part one, and Psoas Major which I am analysing in this article. Without a doubt this is one of the most misunderstood muscles in terms of its function and as a result its influence on dysfunction around the hip and pelvis. For a long time it Psoas has been referred to as a “hip flexor muscle” and blamed for creating excessive anterior tilt of the pelvis which is a common postural fault with back pain and hip related problems. However when you observe its attachments and how it functions you find out it is more of a stabilising muscle that posteriorly rotates the pelvis! The bigger problem is more to do with a lesser known muscle called Illiacus that works very closely with the psoas major. This changes everything in how you would try to restore function and stability to hip and pelvic problems and in this article I will attempt to explain how this works and the best ways to restore hip function.

Where Is Psoas Major & What Is Its Function?

I must state that I was like most people in how I viewed the role of the Psoas as being a problem muscle and predominately a hip flexor that is excessively tight and needs to be loosened or mobilized. I did not appreciate its true rule and its relationship with the illiacus muscle until I read the books “The Psoas Solution” by Evan Osar, and “Tight Hip Twisted Core” by Christine Koth.

Many years of education and being drummed into you that psoas is tight had created a bias and misunderstanding of this muscle that had led me to create poorly designed programs and methods. It is only when things do not seem to be working and you go looking for other answers that you find out great information and a different way of thinking and with both of these practitioners that is exactly what happened to them.

Without getting too technical and including too much medical jargon I will explain what I learned and how it helped me get my head around problems with the hip.

Basic descriptions of the actions of psoas major are flexion and lateral rotation of the thigh at the hip. It also has the ability to flex the trunk at the hip and flexes the trunk laterally. What is not commonly known about Psoas major is that it is a key postural muscle during standing to help stabilise the spine by maintaining normal lumbar lordosis and indirect thoracic kyphosis.

Psoas is more of a trunk stabilizer than a hip flexor

There are a number of attachments of the psoas muscle at every vertebrae level from the lower thoracic spine and lumbar spine connecting via fascial attachments of various muscles around the spine and pelvis suggesting it has much more of a role with the spine than the hip. In addition to that because it is located so close to the spine it is not able to contribute with much movement but aid in stabilisation instead.

This was confirmed in simple single leg raise test with EMG showing activity of Psoas in both the leg being lifted and the leg left on the ground. (Hu et al. 2011)

The most interesting aspect I found is how the Psoas actually creates a posterior tilt of the pelvis to counteract the anterior tilt from illiacus and other more powerful hip flexor muscles like the TFL and rectus femoris. This is the exact opposite of what many people still believe and as a consequence they spend too much time trying to release the psoas and miss treating the underlying problem further exacerbating the dysfunction of the hip.

One could argue it is actually helping you instead of hurting you.

Another interesting feature is how psoas actually tries to centre the femoral head within the acetabulum a bit like the rotator cuff muscles of the shoulder. The main hip flexor muscles actually lift the hip into flexion and the psoas contributes to this by compressing and maintaining the femor head within the acetabulum. This makes a lot of sense as to what its role really is and how it can be confused with other muscles, in particular the illiacus muscle.

There is a great article by sports injury bulletin that showed from results of several studies that the Psoas major counteracts the action of iliacus during hip flexion.

“They believed that the iliacus would torque the pelvis into anterior pelvic tilt and that the psoas works against these forces, adding to the stiffness within the pelvis and the lumbar spine. An activated and stiffened psoas will contribute some shear stiffness to the lumbar motion segment.”

Reference: Medicine & Science In Sports & Exercise. 1998. 30(2):301-310, 1998; 23(18):1937–1945, 1995; 20(2):192–198

This is where I found the work of Christine Koth to be very interesting which is what led her to an important discovery and the reason for writing her book.

Illiacus is The Bigger Problem

Most people refer to the illiacus and psoas together and it is often termed “iliopsoas”. While these muscles share a similar attachment they function independently of each other.

They more or less act as a functional antangonist to each other as I described earlier where the illiacus anteriorly tilts the pelvis and the psoas posteriorly tilts the pelvis. This enables the spine and the hip to be stabilized effectively during movement when it is all working well.

However, if the illiacus is subjected to constant shortening it can become hypertonic and that is when everything starts to fall apart as it excessively rotates the pelvis. The picture below shows what happens when the illiacus becomes over-active on one side of the body creating a chain reaction of problems at multiple joints. This is often referred to as lateral pelvic tilt or leg length discrepancy when in many cases it is a muscle imbalance started at the hip or the feet creating a chain reaction of asymmetry throughout the body as shown below.

Leg length difference as a condition comes in two types.

1. The anatomical type
2. The functional type

The anatomical type is quite rare, for while some of us may have a small difference in leg length it is uncommon for legs to be so different in length that it makes the hips uneven. According to the American Academy of Orthopaedic Surgeons, a difference of about 4cm can cause walking difficulties or a limp.

Exercise intervention is very limited in these cases as this is a structural problem with the skeletal system but as I just mentioned this is very rare.

The functional type is the more common way a leg length imbalance is created which is linked to postural muscle imbalances and these imbalances can be traced back to repetitive movement strategies. More on this shortly

Due to the Illiacus insertion point on the pelvis is what creates all the problems. This is where it begins to pull it forward too much and strain the sacroiliac joint located at the base of the pelvis which is tilted upwards as a result and hits the tailbone as these two bones more or less rub each other. This can be extremely painful and set off a chain reaction of spasms and tension at other muscles, which in turn creates more weakness and more dysfunction at other muscles, most notably the glutes.

When the glutes become inhibited and weak, the hip flexor muscles of TFL and rectus femoris are more heavily active creating an excessive anterior tilt. This is when you begin to get internal rotation of the femur (thigh bone).

This is a disaster for the knee as this joint is exposed to tremendous pain and problems whenever it is forced into a twisting movement, bent sideways, or hyper-extended. This joint is more or less a hinge, it cannot twist and rotate itself, or bend the other way either. Constant shearing of this joint is what leads to chronic injuries like patella-femoral tracking, meniscus tears, ACL tears and eventually chronic osteoarthritis if left untreated.

Also, problems at the feet and ankle will be seen as the tibia begins to rotate inward causing the foot to excessively pronate (flatten) leading to problems like plantar fasciitis, Achilles tendon strains and bunions with the big toe.

Lastly, you cannot ignore what happens above the pelvis and this is where the psoas and the quadratus lumborum get involved and react to the dysfunction caused below. While the Psoas does connect to the femur most of its work will be involved with trying to stabilize the spine and counteract the illiacus. The QL will be actively working in the lateral direction as discussed in more detail in the previous article.

What you end up is a constant tug of war between muscles trying to negate each other and spasms, lack of mobility, weakness, and ultimately pain is the end result until it is resolved.

As you can see you could very easily end up with back pain, knee pain, and foot pain all the same time!

What Happens To The Hip When Psoas Becomes Dysfunctional?

Two important points I think are important to discuss that relates specifically to the role of Psoas is what happens to the hip joint. As discussed earlier the Psoas acts more like a stabilizer of the hip than a prime mover, much like the rotator cuff of the shoulder.

When all the constant tug of war between illiacus, TFL, and rectus femoris muscles and Psoas is occurring, the chances of these muscles developing trigger points from over-working is significantly increased. Not only are these painful and create a series of imbalances but it disrupts the joint centration of the hip joint.

The deep muscle fibres of the gluteus maximus plays a massive role in working with the Psoas major to centre the femoral head within the acetabulum and also provide hip extension which counters hip flexion. Unfortunately, it will be severely limited in being able to do this due to muscle inhibition from illicacus pulling in the other direction and eventually becomes very weak.

Weakness with the glutes will inevitably force the hamstrings to work harder to pick up the slack as they are part of the posterior chain involved in hip extension which ruins the hip stabilization even further. This is easily seen when you ask the person to complete a single leg bridge on the floor and the hamstring cramps up almost instantly.

This is the most common cause of anterior femoral glide (hip impingement) shown below.

It is no surprise that those who suffer with SIJ pain or Piriformis syndrome will often show signs of this hip impingement as well due to the glutes becoming so weak and the illiacus, TFL, and rectus femoris becoming short, tight, and hypertonic.

This will happen well before the severe pain begins and the chronic weakness so if you have a good assessment process you can spot this early on and prevent all these big problems.

What Causes The Illiacus and Psoas To Tighten?

As always there is never just one way this happens but many and it will vary from person to person. Having said that the most obvious and common culprit is sitting. It is not so much the activity of sitting that is bad, but the way you sit, and how long you are stuck in the seated position that causes all of the trouble.

The illicacus and psoas muscles are actively engaged the entire time you sit as the illiacus keeps your pelvis stationary relative to your thigh bone and your psoas keeps your spine straight while you sit. If you get stuck sitting for a long the illiacus can develop trigger points as it has been stuck in a contracted position for too long. This is why it is good to take regular breaks and keep the hips moving.

The way you sit can have a massive influence on whether you develop trigger points or not. This is something I discussed in great detail in the article about the Gokhale Method where Physiotherapist Esther Gokhale created some great ways to modify seated positions to take the strain off the hips and lower back. I highly suggest to read the article – Great lessons I learned from Esther Gokhale about back pain

Other main factors that can contribute greatly to these problems at the hip include;

• Running
• Cycling
• Maximal weight training

While these activities are all great for the body the volume and intensity of the training must be closely monitored to ensure the hips are not overly stressed and exposed to trigger points and imbalances. Poor running technique is a really big concern for very rarely do people pay any attention to how they run and just think the body will work it out if they run more. This is also a problem for almost any sportsperson who neglects this fact as it can really cause a lot of trouble later on.  

The other two bigger factors I find that can cause hip problems among the general population are.

• Hypermobility
• Poor core training techniques and exercises

Firstly, hypermobility is something I come across a lot more often these days with so many females participating in Yoga and Pilates who try to excessively stretch their joints. While mobility is good to have if it is not controlled it can become a big problem. When the hip joint becomes too flexible the psoas and illiacus will tend to tighten to protect the joint from harm and hold everything together.

You can read more about this here – Why stretching is a disaster for hypermobile people

The second and more problematic factor is poor training techniques, in particular with core exercises. It is ironic that the very reason people use core exercises is to try and prevent back and hip pain, yet their poor understanding of movement ends up creating one using these exercises.

Have you ever wondered why you can do so many more sit-ups when someone holds your feet? This is because you can recruit your hip flexors and especially psoas into the movement.

If this is done repeatedly your psoas begins to get short and tight and your abdominal muscles get weaker as the psoas steals their work. In essence your core just got weaker and now you have tight hips. This defeats the whole purpose of the exercise which was to strengthen your core.

You can read more about this in the article – Are core workouts over-rated?

A much better abdominal exercise that avoids this is the lower abdominal strengthening exercise.

I like to use this exercise as a test with people on the first day for it tells me several things about how they move. I tend not to think of it as just a simple strength test, but more as a way of assessing how they choose to provide stability to their pelvis and spine.

This exercise reveals if the psoas and illiacus have learned to become stabilizers of the pelvis, instead of providing movement and in turn have disabled the abdominal muscles from firing first. There is no way you can maintain a neutral pelvis and lumbar spine if you are using your hip muscles to do all the work.

Watch the video below to see this in action.

Now that we have defined what the psoas and illiacus do and what causes them to tighten up what do you need to do to restore function or prevent them from tightening up in the first place?

How To Restore Function Back To The Hip

Firstly, if we look at restoring function the very first thing you need to do is release the chronic stiffness and trigger points that are going to prevent you from stabilizing and strengthening weak muscles like the glutes.

The worst thing you can do is start trying to excessively stretch the front of the hip with crazy stretches like the one shown below. When we feel pain and tightness at the front of the hip we immediately conclude we need to stretch it out, however, it is not tightness but the head of the femur smashing into the bone of the acetabulum. If you start doing these types of stretches you actually make the front of the hip more unstable, which as a direct result makes the psoas, illiacus, and the glutes tighter!

This is where the work of Christine Koth is very useful and her unique rehabilitation tool called “The Hip Hook”. You can read here detailed instructions of how to use this on her website here.

What she found during her clinical work as a physical therapist was that she found during her assessment of patients that came to see her for help with hip and knee pain was a common theme, a tight psoas and illiacus. She knew that stretching these muscles is difficult and usually very ineffective due to their design and location, however releasing spams and trigger points via deep tissue massage is very effective.

What she found is that her patients would feel good after her treatment but fall back into the stiffness days later and needed constant tuning up until it was eventually released for good. She thought if only they could do this trigger point release themselves more regularly then they would be able to hold the adjustment that she just gave them.

But how do you massage yourself in this spot with your own hands?

Even if you had the skills and knowledge to self-massage yourself it is virtually impossible to do this due to the location of the muscle. After experimenting with foam rollers, small balls, kettlebells, and various other tools she ended up creating the hip hook which allows the person to access the illiacus and the psoas at the same time!

She designed the tool (see below) to replicate the pressure that any skilled practitioner like herself would use to ensure the treatment would be as successful.

Now if you don’t have a hip hook you can still work on this using a small massage ball to get into the area. It is not quite as effective but better than nothing.

In addition to this you will need to assess your mobility with anterior quadriceps stretches and foam rolling, and the posterior glutes.

Quadriceps dominance is inevitable when there is a problem with the hips and they will continue to feed the problem if not addressed.

Even though the glutes may be very weak they are often quite tight and held in gripping position of posterior tilt. It is impossible to build adequate strength to counter the pull from psoas and illiacus when the glutes are in constant gripping. This means you need to find a way to release this stiffness so you can get to the next stage of strengthening.

Watch the video below for some ideas of how to release the hips via various basic stretches and drills.

Often I use these mobility drills and trigger point release between sets of the following exercises. Doing it separately I found does not work as well and the stiffness just returns for the body senses the hip is still unstable. If I add the corrective strengthening exercise immediately after the mobilization the body will not need to bring the stiffness back. Of course you will need to do this for some time for it to remain like this by itself but I found it is considerably faster in restoring dysfunction than doing the mobility and stability stage separately.

Strengthening The Glutes are the Key

It seems like almost every article write I am saying the glutes are the key. Along with the feet they are a constant source of weakness as they are the antagonists to the tight dominating muscles so it makes perfect sense that they are always a problem.

Now this is where it gets interesting for your choice of exercises here is critical.

If you just start throwing a random set of glute exercises at this you will create more problems. Exercises that try to strengthen the glutes in a shortened position such as hip extensions, clamshells, and hip thrusts will not work very well and will often cause more pain and suffering. This is because the glutes need to be strengthened in their lengthened position and not the shortened position.

For example, the clamshell which is often a favourite glute exercise for many people will excite the TFL and end up tightening this muscle along with the illiacus instead of strengthening the glutes which defeats the point of using the exercise in the first place.

You can read more about this in the article – Is the clamshell really that good for the glutes?

The worst thing you can do is try to continually posterior tilt the pelvis with exercises and eradicate the anterior pelvic tilt. This is something I have come across a lot over the years and it ties in with the myths surrounding psoas as a problem hip flexor.

A slight anterior pelvic tilt is perfectly normal with a neutral posture.

• For males, the optimal range of tilt is between 5-7 degrees.
• For females, the optimal range of tilt is between 7-10 degrees.

This anterior pelvic tilt provides your lumbar spine with a small lordotic curve which is perfectly normal. This position is essential to the health of the spine and provides a stable and strong base required for efficient movement. Problems arise when there is either too much curve or not enough curvature of the spine and this is greatly influenced by the position of the pelvis.

The key is to use exercises that control and strengthen this neutral position.

I have found exercises like the Romanian Deadlift and bird-dog will have a much greater effect on releasing the stiffness and strengthening the weakness within the glutes than most other glute exercises. This is because they both force the glutes to open up but remain strong at the same time. They are easier to control the neutral position where the tug of war is held in balance allowing for maximal strengthening of the weakened prime movers and prevents any gripping strategies often used with hip thrusts and bridges.

The big problem with these exercises is that are also the ones that can cause the most pain! Especially single leg exercises as this brings the feet into play and the role of the glute medius. People suffering with piriformis syndrome will know exactly what I mean for these exercises can put a lot of pressure on the sciatic nerve which is extremely painful if not managed correctly.

What else can you do?

Exercises To Enhance Glute Function During Movement

It is impossible for me to list the exact exercises I might use and in which order for even though I have been able to help many people over the years the specific exercises vary from person to person.

Starting with simple exercises and working my way up is the best way forward.

If you have implemented the hip hook, mobilized the quads and glutes, and started working on the lower abdominal exercise from earlier you are making good inroads.

Variations of the Romanian Deadlift such as the lateral band distraction and uneven deadlift are great ways to gradually increase the strength demands without aggravating the problem.

Once I have worked on those I want to start building up to single leg strength exercises for I know these are going to have a much bigger effect. However, I don’t want to rush into it so I like to use exercises to minimize this danger.

One of them is an exercise I have been using recently where there I use a hip-hinge movement that is not entirely single leg and also uses momentum to get out of the weak point quickly. This exercise works really well by applying a resistance band to combine two types of hip extension within a single movement. It is this movement that the glute medius usually tries to take over, but using the band on the second part of the movement helps to engage the glute maximus more effectively and therefor preventing the problem often associated with glute exercises.

If this works well I can then gradually progress to a single leg position with an emphasis on improving the glutes strength with hip extension required for walking. This means I need to bring into play the role of the feet for I know they will have an influence over the function of the hips and glutes.

The feet drive the reflex stability of the hip and in particular the big toe acts as the catalyst for optimal glute engagement. If you struggle to activate your glutes during walking try to actively dorsiflex your big toe just prior to heel strike as this helps to increase the stiffness of the foot in preparation for impact with the ground.

Once I have these exercises in place I can begin teaching the entire body how to work together and this is where I start to use multi-joint exercises that utilize the slings of the body. This is exactly what I did in the previous article with quadratus lumborum and exercises that feature the posterior sling and lateral sling are vital. I won’t go into all of those details again as you can read in the article about the QL. The videos of the main exercises I use are shown below.

Lastly, you can start isolating the glutes and hip in the single leg stance with loaded exercises like single leg deadlifts and single leg squats and hopefully by this stage the hip does exactly what it is meant to do. You should have enough strength in the glutes to counter the tug of war from the psoas and illiacus and if you have done everything right you should start to feel well balance and free of pain and limitations.

If you are not in pain and don’t want to be, then all these exercises are something you should be doing now. Avoid sitting too long and make sure you adopt good postural habits. Spend the time to mobilize your hips if you need it and learn how to look after the strength of your glutes by doing deadlifts, single leg exercises and multi-joint movements. Also do not disregard the benefit of going for regular walks as it is one of the best ways to preserve good hip function.

Do You Need More Help? 

Throughout this article, I state several times that specific injuries require detailed assessing to find the source of the problem. To keep this article short I have not included all of these assessments but provided you with links to specific online programs you can instantly download. These programs contain 60-90 minute videos that are downloaded to your phone, tablet or desktop. You do not need a DVD player. There are also detailed PDF reports with all of our best exercises, assessments, mobility drills and strength methods with easy to follow instructions to guide you on finally getting rid of these painful injuries.

Click on the image below of the program you require.

Summary

I hope you enjoyed reading this article and it gives you a better understanding of the psoas major muscle and the lesser known illiacus. As discussed in the article about the QL in part one the psoas is really more of a stabilising muscle than a prime mover and problems associated with this is more from a protective mechanism than anything else.

The illiacus on the other hand is much more of a problem and along with the weakness of the glutes it goes unnoticed leaving the problem to fester and get out of hand. By understanding the hip anatomy and function better you can make better decisions about how to restore it and look after it.

For more ideas and information on specific topics I may not have covered in detail be sure to check out our INDEX PAGE on the website that has over 300 of our best articles. These are all sorted into categories for quick reference so you can find what you are after more easily. 

If you do need specific help with your exercise program please feel free to reach out to me for help and we can set you up with your individualised program.

About The Author

Nick Jack is owner of No Regrets Personal Training and has over 19 years’ experience as a qualified Personal Trainer, Level 2 Rehabilitation trainer, CHEK practitioner, and Level 2 Sports conditioning Coach. Based in Melbourne Australia he specialises in providing solutions to injury and health problems for people of all ages using the latest methods of assessing movement and corrective exercise.

References:

• Tight Hip & Twisted Core - By Christine Koth
• Psoas Solution - By Evan Osar
• 8 Steps To Pain Free Back - By Esther Gokhale
• The Vital Glutes - By John Gibbons
• Movement - By Gray Cook
• Corrective Exercise Solutions - by Evan Osar
• Back Pain Mechanic - by Dr Stuart McGill
• Diagnosis & Treatment Of Movement Impairment Syndromes - By Shirley Sahrman
• Low Back Disorders - by Dr Stuart McGill
• Ultimate Back Fitness & Performance - by Dr Stuart McGill
• Knee Injuries In Athletes - by Sports Injury Bulletin
• The ACL Solution - by Robert G Marx
• Athletic Body in Balance - by Gray Cook
• Anatomy Trains - by Thomas Meyers
• Motor Learning and Performance - By Richard A Schmidt and Timothy D Lee
• Assessment & Treatment Of Muscle Imbalance - By Vladimir Janda
• How To Eat, Move & Be Healthy by Paul Chek
• Scientific Core Conditioning Correspondence Course - By Paul Chek
• Advanced Program Design - By Paul Chek