Groin Pain - Ischiofemoral Impingement

Groin pain is a common complaint with many conditions of the hip, particularly in hockey players. It tends to go hand in hand with hip impingement (FAI). A lesser known condition that can cause it is called ischiofemoral impingement (IFI). This means there is a decrease in space between the femur and pelvis, and a small muscle of the hip socket (quadratus femoris) gets compressed.

What causes the decrease in space? Pelvic width plays a role which predisposes women to be at higher risk. Genu valgus (knock-kneed) could also contribute to IFI because the femur is in an adducted position. For the same reason, weakness or injury in the hip abductors can lead to IFI because it allows the femur to be in an adducted position. Lastly, surgery can be to blame. Look at the distance between the femur and the pelvis in the repaired leg.

Image from “Hip Impingement, beyond femoroacetabular” Bardakos, 2015.

How does one know if they have it? Usually resisted hip external rotation will be painful. But even more commonly, a position of adduction, external rotation, and extension will provoke pain, like so:

There is some symptom overlap with FAI as one theory of the etiology of FAI is a shortening of the external rotators of the hip from laxity in the front of the hip, as explained in this blog post. So in one scenario, we have a shortening of the quadratus femoris causing pain in the buttock and radiating pain in the groin and medial thigh, and in another scenario, we have a decrease in space compressing the same muscle causing the same symptoms. In both scenarios, the muscle has to be addressed to reduce symptoms. Here is a video on quadratus femoris release:

References:

Bardakos, N. V. (2015). Hip impingement: Beyond femoroacetabular. Journal of Hip Preservation Surgery, 2(3), 206-223. doi:10.1093/jhps/hnv049

Quadratus Femoris and Hip Impingement (FAI)

Dancers frequently develop hip pain. Hip impingement is a common diagnosis which means there is pain in the front of the hip with movements like hip flexion and internal rotation. Usually a change in the shape of the bone in the hip is to blame, but is there more to it? We don’t know for sure, but it’s complicated.

The quadratus femoris is a small rectangular muscle, deep in the hip socket. It is an external rotator and adductor of the hip. Although uncommon, tears and strains of this muscle can cause pain in the groin, posterior hip, and even cause radiating pain from irritation of the sciatic nerve. 

This set of symptoms overlaps with the pain that people experience with hip impingement. So what is the connection? With hip impingement, internal rotation of the hip is painful, and in this blog post, I explain one possible reason this pattern develops. As a person with hip impingement flexes the hip (think knee to chest), the hip will sway towards external rotation to avoid the painful internal rotation motion. The theory is that this leads to adaptive shortening of the quadratus femoris. The muscle becomes irritated and painful, and may even lead to what is known as ischiofemoral impingement (IFI), where the femur has abnormal contact with the pelvis (Gollwitzer et. al, 2017). It has been proposed that when this muscle becomes inflamed, it can leak onto the sciatic nerve which runs just posterior to this muscle and cause radiating pain down to the knee (Kassarjian et. al, 2011).

The yellow cord is the sciatic nerve, “Q” is quadratus femoris

The clinical presentation of hip impingement can be very complicated, and subsets of issues tend to come along with this diagnosis. It is difficult to determine if hip impingement may cause a shortening of the quadratus femoris, or the other way around. Regardless, lengthening this muscle and restoring range of motion of the hip, and strength in the hip abductors should be prioritized.

Here is an example of how to release quadratus femoris:

Here is an example of restoring hip internal rotation (make sure this is pain free):

And finally to strengthen the hip abductors, you can do sidelying leg raises. Here is an alternative exercise that is great for the hip abductors:

References:

Gollwitzer, H., Banke, I. J., Schauwecker, J., Gerdesmeyer, L., & Suren, C. (2017). How to address ischiofemoral impingement? Treatment algorithm and review of the literature. Journal of Hip Preservation Surgery, 4(4), 289-298. doi:10.1093/jhps/hnx035

Kassarjian, A., Tomas, X., Cerezal, L., Canga, A., & Llopis, E. (2011). MRI of THE Quadratus FEMORIS Muscle: Anatomic considerations AND Pathologic Lesions. American Journal of Roentgenology, 197(1), 170-174. doi:10.2214/ajr.10.5898

SI Joint Pain and Hip Impingement (FAI)

Hip impingement, or femoroacetabular impingement, is pain in the front of the hip that occurs with hip flexion and internal rotation. Sometimes, patients with FAI also get pain in the back side. The sacroiliac joint (SI) is usually the culprit. To read more about the SI joint, check out this blog post. 

Why does this so frequently happen? A principle of the body is that where there is an area of stiffness, the neighboring area tends to ‘pick up the slack’. In other words more strain is induced in the SI joint (Hammoud et. al, 2014). It’s similar to the shoulder. If you are missing internal rotation, and you try to reach behind your back, your whole shoulder girdle will tip forward. The same thing happens with the hip. Hip internal rotation is usually very painful and limited in FAI. So as the femur starts to rotate into internal rotation, the pelvis shifts away from the pain and creates torsion at the SI joint. This joint is embedded with a ton of ligaments and they are not contractile like a muscle, so they get inflamed from being stretched. If it gets bad enough, the inflammation ‘leaks’ onto the surrounding nerves and can send pain down the leg.

In a similar mechanism, stress can occur at pubic symphysis, the area in the front where the bones meet. Groin pain is strongly associated with FAI, and this may be the underlying mechanism. This is not to be confused with osteitis pubis, which is pain where the adductor inserts into the pubic tubercle. With osteitis pubis, pain will be elicited with flexion, abduction, and external rotation; the FABER position (Gomella & Mufarrij, 2017). 

Another point of confusion is that posterior pain can also be from the hip capsule. When there is a cam deformity present, as the hip is flexed and internally rotated, the head of the femur is levered into the socket, placing stress at the back side of the capsule (Hammoud et. al, 2014). See below:

Photo taken from Hammoud et. al, 2014. The red arrow is the front and the black arrow is the back.

Seeing that lack of range of motion seems to be at the heart of the problem, restoring flexion and internal rotation will reduce strain at the SI joint. For some patients, placing a lateral distraction force helps them get into a better position. However, every person is different so this should only be done if it is pain free. Here is an example:

Think this might be you? Let’s get on a free phone call and figure it out.

References: 

Gomella, P., & Mufarrij, P. (2017). Osteitis pubis: A rare cause of suprapubic Pain. Retrieved February 25, 2021, from https://www.ncbi.nlm.nih.gov/pubmed/29302238

Hammoud, S., Bedi, A., Voos, J. E., Mauro, C. S., & Kelly, B. T. (2014). The recognition and evaluation of patterns of compensatory injury in patients with Mechanical HIP PAIN. Sports Health: A Multidisciplinary Approach, 6(2), 108-118. doi:10.1177/1941738114522201