9 - Important Points

Question 1

What is the origin of the superior gluteal nerves?

Answer 1

L4 - S1

Question 2

What is the origin of the inferior gluteal nerve?

Answer 2

L5 - S2

Question 3

What is the course of the inferior gluteal nerve

Answer 3

The inferior gluteal nerve leaves the pelvis through the greater sciatic foramen and runs underneath the piriformis muscle. It the divides into muscular branches to supply the gluteus maximus that pass posteriorly into the deep surface of the gluteus maximus muscle`

Question 4

What is locking of the knee?

Answer 4

When the knee is fully extended with the leg and foot on the ground, the knee “locks” because of medial rotation of the femur on the tibia. This movement enables the lower limb to become a solid column to support the weight of the body. In the locked position, the thigh and leg muscles relax without making the knee joint unstable.

Question 5

How does the knee unlock?

Answer 5

In order to flex the knee, the knee has to “unlock”; this is done by contracting the popliteus muscle which results in rotating the femur laterally on the tibia so that flexion of the knee can take place.

Question 6

What happens to ligaments when knee is locked

Answer 6

They get tighter

Question 7

Why would a torn medial meniscus present as knee locking?

Answer 7

A torn meniscus may result in it becoming dislodged (or its fragment breaking away) and becoming trapped within the knee joint cavity causing the knee to become “locked”.