(3.20)
Now that we’ve looked at the dry bones, let’s see how they look in the living body. The big gap between the sacrum and the ischium is bridged by two massive ligaments. The sacro-spinous ligament goes to the ischial spine, the sacro-tuberous ligament goes to the ischial tuberosity. Let’s go round to the front and see those two ligaments from the inside. Here’s the sacro-spinous ligament, here’s the sacro-tuberous ligament. These two openings are the lesser sciatic foramen, and the greater sciatic foramen. The sciatic nerve passes through the greater sciatic foramen. The obturator foramen is largely closed by the obturator membrane. The obturator nerve and vessels pass through a small tunnel here.
Now let’s take a look at the hip joint. We’ll remove the femur for a moment, and look at the acetabulum. Here’s the broad, c-shaped articular surface, sometimes called the lunate surface. This non-articular part of the acetabulum is the acetabular fossa. Around the edge of the bony acetabulum this rim of fibrocartilage, the acetabular labrum, adds to the depth of the acetabulum.
This is the cut end of the ligament of the head of the femur. Its other end is attached here, on the center of the femoral head. Now let’s go back to the intact hip joint.
The capsule of the hip joint is a sleeve of ligaments. The capsule is thin on the underside. Everywhere else it’s thick and very strong. This part of the capsule behind is called the ischio-femoral ligament. This anterior part of the capsule, which is the thickest, is known as the ilio-femoral ligament. The fibers of these capsular ligaments become tight when the joint is extended.
The capsule is attached to the hip bone all the way round the acetabular labrum. On the back of the femur the ...
(3.20)
Now that we’ve looked at the dry bones, let’s see how they look in the living body. The big gap between the sacrum and the ischium is bridged by two massive ligaments. The sacro-spinous ligament goes to the ischial spine, the sacro-tuberous ligament goes to the ischial tuberosity. Let’s go round to the front and see those two ligaments from the inside. Here’s the sacro-spinous ligament, here’s the sacro-tuberous ligament. These two openings are the lesser sciatic foramen, and the greater sciatic foramen. The sciatic nerve passes through the greater sciatic foramen. The obturator foramen is largely closed by the obturator membrane. The obturator nerve and vessels pass through a small tunnel here.
Now let’s take a look at the hip joint. We’ll remove the femur for a moment, and look at the acetabulum. Here’s the broad, c-shaped articular surface, sometimes called the lunate surface. This non-articular part of the acetabulum is the acetabular fossa. Around the edge of the bony acetabulum this rim of fibrocartilage, the acetabular labrum, adds to the depth of the acetabulum.
This is the cut end of the ligament of the head of the femur. Its other end is attached here, on the center of the femoral head. Now let’s go back to the intact hip joint.
The capsule of the hip joint is a sleeve of ligaments. The capsule is thin on the underside. Everywhere else it’s thick and very strong. This part of the capsule behind is called the ischio-femoral ligament. This anterior part of the capsule, which is the thickest, is known as the ilio-femoral ligament. The fibers of these capsular ligaments become tight when the joint is extended.
The capsule is attached to the hip bone all the way round the acetabular labrum. On the back of the femur the capsule is attached part-way along the femoral neck. On the front of the femur the capsule is attached out here, on the inter-trochanteric line.
Now let's take a look at the various different movements that occur at the hip joint. Movement can occur in three different axes. Forward movement is flexion, backward movement is extension. Movement out to the side is abduction, movement toward or across the midline is adduction. Lastly rotation. Rotation outward is lateral rotation, rotation inward is medial rotation.
Rotation at the hip joint is accompanied by marked backward and forward movement of the greater and lesser trochanter.