Can you palpate psoas major?

I spent a long time looking at psoas major.

• dissected 27 cadavers
• did a biomechanical model of psoas major on the lumbar spine and SIJ; 
• developed a strategy to view the width of the posterior fascicles on CT imaging (with a reliability and validity study)
• assessed the width of the posterior fascicles in acute LBP
• developed a specific motor control exercise (with others) for psoas; 
• did a deep fine wire EMG pilot study
• measured superficial EMG during the specific exercise
• measured fluoroscopy of the femoral head during the specific motor control exercise
• did a clinical trial on specific motor control stability exercises (including the exercise for psoas major) for acute low back pain
• developed a preliminary clinical prediction rule for who will respond to specific motor control exercise (including the one for psoas major)

Since specific motor control exercises are part of my daily practice, so I have routinely looked at psoas major and other muscles with real time ultrasound imaging since 2000.


I remember an old colleague from the Kinetic Control days describing the palpation of psoas major: "if you can palpate the abdominal aorta, you can palpate psoas major". Can you palpate the abdominal aorta?
https://www.aafp.org/afp/1999/0415/p2343a.html

Yes you can (in many people)


There are three potential places that you can palpate psoas major:

• abdominal
• pelvic brim and 
• lesser trochanter. 

Can you palpate psoas major? I don't know if you can palpate it directly. Can you exert force on psoas major? Yes you can likely do this in people with normal BMI. Can you do this reliably? I doubt it, but I don't know. Can you palpate the proposed trigger points in psoas major? I doubt you could do this with reasonable reliability (if they exist). I certainly wouldn't want to do that study.

I know that many years ago I tried palpating it at the lesser trochanter. I always found something "tender" but never knew what I was palpating so gave up. I have never tried palpating it at the pelvic brim (iliopectineal eminence), although some anatomists I worked with said you should be able to in people with normal BMI. Once again though, I am not sure of the reliability. There are a lot of potentially tender structures in there to get confused with.

Do I palpate psoas major in my clinic? It is pretty uncommon actually. But this is due to a few reasons. 1: the issues mentioned above: 2: because I have 30 min with someone and if don't see that as time well spent (most of the time). Since primitive reflex inhibition appears to normalize muscle tone, I would rather spend my time doing that. I also make sure I spend some of my session (if not all) giving education and teaching some form of exercise (most often some form of specific motor control). When would I attempt it? I may do this in someone with normal to below average BMI who is in acute pain and who may benefit from some pain relief to perform their specific motor control exercises better or to better perform primitive reflex inhibition.

Do I teach the palpation of psoas major on courses? No I do not. If you do not know how to palpate abdominal masses, you should not be trying to palpate psoas major at the abdominal region. As well, I try to keep things on courses that have undergone reliability or at least would allow it to easily be assessed with reliability.

So in summary, you should be able to exert some force on psoas major through abdominal palpation in most subjects with normal BMI.