What are the Deep Hip Muscles and Why are They Important for Hip Pain?

What are the deep hip muscles and why are they important?

Many of us would have heard about the “core” muscles and how important they are for people with back pain, or about the “rotator cuff” muscles and their role in protecting the shoulder. But very few people, even those with hip pain, would have heard about the deep hip muscles and their role in protecting the hip joint.

A group of Australian physiotherapists and leading researches have proposed that the deep hip muscles (glute med, glute min, piriformis, illiacus, illiocapsularis, gemelli and obturator internus) play an important role in stabilising the hip joint. That is because these muscles are situated in a position very close to the hip joint and have a high proportion of type 1, slow twitch muscle fibres. This is the ideal combination for producing a stabilising force around a joint. EMG studies, also show that these muscles activate at times that could only serve to stabilise the hip joint.

So why is this important?

Many of the common hip injuries such as osteoarthritis, trochanteric bursitis, femoracetabular impingment (FAI) and labral tears can be the result of excessive movement or laxity in and around the hip joint. At the same time, research has shown that when we have pain in a joint, the muscles that stabilise that joint often stop working properly, they switch on too late or atrophy. So identifying these muscles in the hip joint gives options for rehabilitating these important muscles. If these muscles do play an important role in stability, then making sure they are strong and functioning well could help prevent hip problems.

How Can we Assess and Rehabilitate the Deep Hip Muscles?

Because the deep hip stabilisers are quite small and quite deep, we use real time ultrasound to identify these muscles in physiotherapy and check if they are functioning well. We can also prescribe exercises to target these muscles, again using real time ultrasound to check the exercises are being performed well. Once the patient is able to recruit and switch on these deep muscles well, we then move on to more functional exercises that recruit larger muscle groups too.