Hip Joint

00:01 Let's start with the Hip joint.

00:04 So the Hip joint is a synovial ball and socket joint.

00:09 It's the articulation between the head of the femur into the acetabulum of the pelvis bone.

00:16 So here we can see as we separate the femur from the pelvic bone, we can see we have the head of the femur, and here we have the acetabulum.

00:24 If we look at the lateral view, we can see the acetabulum here indicated with this black dotted line.

00:31 To the right hand side of the screen, we have the anterior aspect where we can see the pubic symphysis just protruding out.

00:38 And the ischial tuberosity is down in the lower left hand side projecting posteriorly.

00:43 But here we have the acetabulum.

00:45 This circle indicated via the black dotted line.

00:49 It's made up of those three bones that we've spoken about that form the pelvic bone.

00:54 We have the ilium in green, the ischium in blue, and the pubis bone here in red.

01:00 These three surfaces give rise to what is the articular surface of the hip joint, which is this lunate surface, that has this very characteristic shape.

01:10 We also have the acetabular fossa.

01:13 And this doesn't actually have any articulation with the head of the femur.

01:17 Surrounding these surfaces is the hyaline cartilage.

01:21 And that creates that smooth surface for the head of the femur to articulate with.

01:26 Running circumferentially around the acetabulum, we have the acetabular labrum and this increases the articular surface.

01:34 Increasing the bone congruency, that space in which the head of the femur can articulate.

01:40 It helps to further stabilize this important joint.

01:44 Just connecting that lunate surface where we've got the hyaline cartilage, we have an important ligament.

01:50 This is the transverse acetabular ligament, and it's positioned posteriorly where there is a deficiency in this hyaline cartilage.

01:59 In there, we can then see the acetabular foramen, and we'll come back to this in later detail.

02:04 Running through from this acetabular fossa, we have the ligament of the head of the femur.

02:09 And that passes into the fovea, which we'll see later on in the head of the femur.

02:15 So now let's have a look at the head of the femur.

02:17 And this is a right femur, we're looking at his anterior surface.

02:21 Here, we have hyaline cartilage covering the articular surface of the head of the femur.

02:27 And here we have that fovea, which is for the ligament of the head of the femur, and this helps to hold the femur in position.

02:35 Here we can now see the ligament of the head of the femur on the screen.

02:39 Here we can see the head of the femur is positioned with in the acetabulum.

02:44 And surrounding it, we have a joint capsule.

02:47 So this is a joint capsule that surrounds that joint and helps to hold the head of the femur in position.

02:54 We can see it's attaching medially on to the pelvic attachment around the margin of this acetabulum.

03:00 And the adjacent margin occurs around the obturator foramen.

03:04 We also have it attaching onto the intertrochanteric line anteriorly on the femur, and also on the neck of the femur posteriorly.

03:14 Now, let's turn our attention to the ligaments that help to support the hip joint.

03:19 These ligaments are very much named after the bones which they originate from.

03:24 So here we have the Pubofemoral ligament.

03:27 Here we have the Iliofemoral ligament.

03:29 And more posteriorly, we have the Ishiofemoral ligament.

03:33 So these ligaments are running alongside the joint capsule.

03:36 We have three of them, which originate from those three bones that form the acetabulum.

03:41 Iliofemoral, Pubofemoral, and Ishiofemoral ligaments.

03:46 Here we can see the blood supply that goes to supply the joint capsule around the hip.

03:50 It's originating from numerous branches including the obturator artery, the femoral artery, and the deep artery of the thigh.

03:58 All of these main trunks give rise to numerous branches that surround the hip joint and give it a wide range of blood supply.

04:06 For example, we have the superior and inferior gluteal arteries originating from the internal Iliac artery.

04:13 We then have the two circumflex arteries, medial and lateral, which are coming from the deep artery of the thigh.

04:19 So we spoke previously in the overview of the blood supply to the lower limb that these form an important and that's demotic loop around the hip joint.

04:30 Specifically, we touched on how the obturator artery passing through the obturator canal that deficit in obturator membrane.

04:37 How its two anterior and posterior branches form an important anastomosis.

04:42 This gives rise to an acetabulum branch that passes all the way to the head of the femur running within the ligament of the head of the femur.

04:51 So an alternative blood supply that's running straight in to the substance of the femur itself.

04:58 So now, let's look at the movements that occur at the hip joint.

05:02 We have the femur moving anteriorly here within the sagittal plane, and that is going to be Flexion.

05:08 We also have the femur moving posteriorly here within the sagittal plane, and that is going to be Extension.

05:14 We also have the femur able to move towards the midline and we call this Adduction.

05:19 We also have the femur then moving laterally away from the midline, and this is going to be Abduction.

05:27 We also have a degree of rotation at the hip joints, we have external or lateral rotation, and we can also have medial or internal rotation.

05:36 So a range of movements that can occur at the hip joint.