Video: Muscles of the hip and thigh

Athletes like Usain Bolt, Serena Williams, and Wayne Rooney – ever wondered what helps them dominate the sports world with such remarkable success? Well, among dedication, hard work, and a bucket load of talent, their well-trained muscles of the hip and thigh also deserve a little credit. Regardless of whether you strive towards becoming an athlete, a sports doctor or basically anything in between, the anatomy of this particular muscle group will literally get you moving in the right direction, and in this tutorial, we'll be finding out why. Let's explore the muscles of the hip and thigh.

Before we start, let me give you a quick overview of what we'll cover in today's tutorial. We'll start off with the muscles of the hip and these can be divided into two groups – the anterior hip muscles and the posterior hip muscles, which are also known as the gluteal muscles. The gluteal muscles can then be subdivided further into the superficial gluteal muscles and the deep gluteal muscles. We'll then go on to look at the muscles of the thigh which can be split into three groups – the muscles of the anterior compartment, the muscles of the medial compartment, and the muscles of the posterior compartment. We'll then bring our tutorial to a close with some clinical notes relevant to the muscles of the hip and the thigh.

So as I said, let's begin with the muscles of the hip starting with the anterior hip muscles.

The first muscle we'll talk about is this large one you can see from an anterior perspective and highlighted in green which is the psoas major muscle. The psoas major originates from the bodies of the vertebrae T12 to L4 and the transverse processes of the vertebrae L1 to L5. Located a bit more laterally, we find another muscle which is known as the iliacus muscle. The iliacus muscle originates from the iliac fossa. Interestingly, the psoas major and the iliacus are usually distinguished as one muscle and this is known as the iliopsoas muscle, and as I've demonstrated already, these muscles have different points of origin; however, they come together to pass underneath the inguinal ligament and into the region of the thigh to insert onto the lesser trochanter of the femur.

Now the last muscle of the anterior hip we're going to be talking about is the psoas minor muscle and as you can see, this is a small muscle that runs along the surface of the psoas major, and this muscle is sometimes not mentioned as it is often absent. Around about 40 to 70 percent of people do not have this muscle.

Before we move on to the muscles of the gluteal region, let me tell you a little bit more about the anterior hip muscles.

So the iliopsoas is the most powerful flexor of the thigh at the hip joint which is the movement we can see in this next image, and in order to carry out their functions, the muscles need innervation. So the iliacus is innervated by the femoral nerve, the psoas major is innervated by the femoral nerve and the lumbar plexus, and the psoas minor if it's present is innervated by just the lumbar plexus. The iliopsoas receives its blood supply from the iliolumbar artery and the medial femoral circumflex artery.

Okay, now it's time to have a look at the muscles of the gluteal region starting with the superficial gluteal muscles.

Before we begin, let's change our perspective so that we can see the hip and the thigh from a posterior view. So there are four superficial gluteal muscles and the first one we're going to be talking about is the gluteus maximus muscle. It's the most famous of the gluteal muscles as it is the muscle that defines the booty – I mean, the buttocks – and is one of the muscles that we use when we get to twerk.

The gluteus maximus originates from the lateroposterior surface of the sacrum and the coccyx, the gluteal surface of the ilium, the thoracolumbar fascia, and the sacrotuberous ligament. It then inserts onto the gluteal tuberosity of the femur and the iliotibial tract.

If we remove the gluteus maximus, the next muscle we'll see is the gluteus medius muscle, and the gluteus medius originates from the gluteal surface of the ilium and inserts onto the greater trochanter.

Deep to the gluteus medius muscle, we find the gluteus minimus and the gluteus minimus also originates from the gluteal surface of the ilium and inserts onto the greater trochanter of the femur.

The fourth and final superficial gluteal muscle is this muscle over here which is known as the tensor fasciae latae, and this muscle extends from its origin at the anterior superior iliac line to its insertion at the iliotibial tract. So I realize that over here, it looks like this muscle is inserting into thin air, so let me change some images to show you the iliotibial tract. The iliotibial tract is essentially a thick strip of connective tissue that connects the tensor fasciae latae and gluteus maximus to the tibia of the leg.

Alright, again, let's talk a little bit about function, innervation, and blood supply of the superficial gluteal muscles. So these muscles are responsible for extension, abduction, and rotation of the thigh at the hip joint and they also assist in stabilizing the pelvis. The gluteus maximus is innervated by the inferior gluteal nerve and the other three muscles are innervated by the superior gluteal nerve. These muscles receive their blood supply from the superior gluteal artery and the inferior gluteal artery.

So now that we've discussed the superficial gluteal muscles, let's dig even deeper and talk about the deep gluteal muscles.

The first of the deep gluteal muscles we'll talk about is the piriformis muscle which we can see here from a posterior perspective. This muscle originates from the pelvic surface of the sacrum and inserts onto the greater trochanter of the femur. Inferior to the piriformis, we can also see the obturator internus muscle, and the obturator internus originates from the obturator membrane and inserts onto the greater trochanter and the trochanteric fossa.

The next muscle we're going to be talking about is the superior gemellus muscle and this muscle originates from the ischial spine and inserts onto the greater trochanter of the femur. If you have a superior gemellus muscle, then you must also have an inferior gemellus muscle and the inferior gemellus originates from the tuberosity of the ischium and inserts onto the greater trochanter and you're probably starting to notice that the greater trochanter is a very popular site of insertion, so just keep that in mind.

All right, so the last muscle of this group is square-shaped and because of this, it is named the quadratus femoris muscle. This muscle originates from the tuberosity of the ischium and inserts into the intertrochanteric crest.

Moving on to the function, innervation, and the blood supply of these muscles, the deep gluteal muscles are responsible for the lateral rotation of the thigh at the hip joint and the innervation is supplied by the sacral plexus. These muscles receive their blood supply from the superior gluteal artery and the inferior gluteal artery.

So that's us finished with the muscles of the hip, it's time to move on to the muscles of the thigh starting with the muscles of the anterior compartment.

So the first muscle of the anterior compartment we'll talk about is the sartorius muscle, and the sartorius muscle is the longest muscle in the human body that extends from its origin at the anterior superior iliac spine all the way to its insertion on the medial surface of the tibia. This muscle has various functions including flexion of the thigh and the knee, abduction and lateral rotation of the thigh, and medial rotation of the knee, and sitting cross-legged like we can see in this new image demonstrates all of the actions of the sartorius muscle.

Deep to the sartorius, we have a group of muscles that come together to form the quadriceps femoris muscle, and this muscle is formed by four muscles – the rectus femoris, the vastus lateralis, the vastus intermedius, and the vastus medialis. These muscles all have different sites of origin; however, they all insert into the quadriceps tendon, and let's move on to look at these muscles individually.

Located most anteriorly, we have the rectus femoris muscle and this muscle originates from the anterior inferior iliac spine and the supraacetabular sulcus. If we remove the rectus femoris, we are able to see the other three muscles more clearly and the one we can see now highlighted in green is the vastus lateralis muscle. As the name suggests, this muscle is located laterally and it originates from the linea aspera femoris and the greater trochanter.

Now in the middle, we can see another vastus which is known as the vastus intermedius muscle and this muscle originates from the shaft of the femur. The next muscle we're going to be talking about is found medially, and therefore, it's no surprise that it's known as the vastus medialis muscle, and this muscle originates from the linea aspera femoris and the intertrochanteric line.

The last muscle of the anterior compartment I'll briefly mention is the articularis genu muscle and it lies deep to the vastus intermedius and is found roughly here. This small flat muscle originates from the anterior distal femoral shaft and inserts onto the knee joint capsule.

So now a few words on the muscles of the anterior compartment.

So these muscles are primarily extensors of the leg at the knee joint but they also have secondary functions, namely, the sartorius and rectus femoris can flex the thigh at the hip joint and these muscles receive their innervation from the femoral nerve and their blood supply from the femoral artery and the deep femoral artery.

So let's move a little bit medially now to look at the muscles of the medial compartment of the thigh, and the first one we'll look at is this one we can see from a posterior perspective which is the obturator externus muscle. Now this muscle originates from the obturator foramen and the obturator membrane and inserts at the trochanteric fossa.

Now let's switch to an anterior view to talk about our next muscle which is the pectineus muscle. The pectineus muscle originates from the iliopubic eminence and the pectineal line of the pubic bone and inserts at the linea aspera femoris and the pectineal line of the femur.

Located most medially, we can see the gracilis muscle. The gracilis is an exception within this group of the thigh muscles because it inserts on the tibia whereas the others insert on the femur, and more specifically, this muscle originates from the inferior pubic ramus and inserts on the proximal medial surface of the tibia.

The next four muscles have adductor in their name and are collectively known as the adductors of the thigh, and the first one we're going to be talking about is the adductor brevis muscle. So brevis means short in Latin and we can see here that it is quite a short muscle. This muscle originates from the inferior pubic ramus and inserts on the linea aspera femoris. And if you have a brevis then you must also have a longus, and here we can see the adductor longus muscle. The adductor longus originates from the pubic symphysis and the superior pubic ramus and inserts on the linea aspera femoris.

The next adductor is rather large and because of this, we call it the adductor magnus muscle. And this muscle originates from the inferior pubic ramus, the ramus of the ischium, and the tuberosity of the ischium and it inserts on the linea aspera femoris and the adductor tubercle. The portion of the adductor magnus that we can still see highlighted is sometimes distinguished as a different muscle known as the adductor minimus muscle and the adductor minimus originates from the inferior pubic ramus and inserts on the linea aspera femoris. And like the greater trochanter, the linea aspera femoris is also a popular insertion point.

So let's move on now to talk about the function, the innervation, and the blood supply of the muscles of the medial compartment and these muscles are primarily responsible for adduction of the thigh at the hip joint, hence, the name but they're also able to flex and rotate the thigh. The main innervation is supplied by the obturator nerve, but some muscles receive additional fibers from the femoral nerve and the tibial nerve and these muscles are the pectineus which receives fibers from the femoral nerve and the adductor magnus which receives fibers from the tibial nerve. The muscles of the medial compartment receive their blood supply from the obturator artery and the deep femoral artery.

All right, so it's time for us now to move on to the last group of muscles of the thigh which are the muscles of the posterior compartment.

The muscles of the posterior compartment are also known as the hamstring muscles and the first one we're going to talk about is the biceps femoris muscle, and we're looking at this muscle from a posterior view and it originates from the sacrotuberous ligament, the linea aspera femoris, and the tuberosity of the ischium. It then inserts onto the head of the fibula.

Located medially, we can see the semitendinosus muscle and this muscle originates from the sacrotuberous ligament and the tuberosity of the ischium and it inserts on the proximal tibia medial to the tibial tuberosity. Deep to this semitendinosus muscle, we have the semimembranosus muscle and this muscle originates from the tuberosity of the ischium and inserts on the medial condyle of the tibia and the oblique popliteal ligament.

All right, let's take a minute to talk about the function, the innervation, and the blood supply of the muscles of the posterior compartment. These muscles are primarily responsible for the flexion of the leg at the knee joint, but they’re also extensors of the thigh at the hip joint except for the short head of the biceps femoris. The innervation is supplied primarily by the tibial nerve which is a division of the sciatic nerve; however, there is an exception. The short head of the biceps femoris is innervated by the common fibular nerve which is also a division of the sciatic nerve, and the muscles of the posterior compartment receive their blood supply in the deep femoral artery.

Before we move on to our clinical notes, let's just take a moment to bring it all together and understand the functional anatomy with some examples. Whether you're a professional athlete or a regular gym goer, you'll probably know that no leg day is complete without pushing yourself with some sets of squats. So squatting is a popular exercise that works several muscle groups across the body – none more so than the muscles of the hip and thigh. And the key players for this are your gluteus maximus, the quadriceps femoris group, and your hamstrings.

Your quadriceps femoris, sartorius, and iliopsoas help to initiate flexion of the hip joint while the gluteus maximus and hamstrings eccentrically control your descent into the squat and then work hard to extend your thigh at the hip joint to push you back upwards. The quadriceps femoris is also responsible for extension of the knee joint. Many other muscles of the hip of the thigh such as the adductor muscles of the medial compartment as well as the deep gluteal muscles help to rotate and support the hip joint to stabilize this movement.

So, there you go, the perfect recipe for building a powerhouse set of hip and thigh muscles.

I also must mention if you want to know more about all the nitty-gritty functions of each of the muscles involved here, why not take some time to check out our awesome 3D muscle function video series on the lower limb. Here, you'll be able to watch each muscle performing their functions in isolation and visualize every movement without missing a thing.

Okay, so now that we're familiar with the muscles of the hip and the thigh, let's get clinical.

A pulled hamstring is a strain of one or more of the muscles found in the posterior compartment of your thigh. It's a common sports injury in individuals who are required to start and stop often or to run very hard. An example of this is a footballer.

So the symptoms of a strained or torn hamstring include pain and swelling on the back of the thigh and it's normally treated with rest, ice, compression, and elevation known as RICE. Medications such as ibuprofen can also be used to alleviate pain and inflammation; however, if symptoms persist, physical therapy may be required, and the risk of hamstring injuries can be reduced by warming up and stretching prior to exercise as this increases the flexibility of the muscles.

Okay, so before we bring our tutorial to a close, let's just quickly summarize what we've learned today.

So we started by looking at the muscles of the hip and then we saw that these muscles can be split into two groups – the anterior hip muscles and the posterior hip muscles which are also known as the gluteal muscles. We then divided the gluteal muscles further into the superficial gluteal muscles and the deep gluteal muscles and then we moved on to look at the muscles of the thigh which we divided into three groups – the muscles of the anterior compartment, the muscles of the medial compartment, and the muscles of the posterior compartment. And finally, we concluded our tutorial with some clinical notes about the hamstrings.

So that brings us to the end of our tutorial on the muscles of the hip and the thigh. I hope you enjoyed it. Thanks for watching. Happy studying!