Sacral plexus

1. From what portion of which nerve roots is the superior gluteal nerve formed?
2. From what nerve roots is the inferior gluteal nerve formed?
3. The nerve to what muscle comes directly off the posterior part of S2?
4. How is the tibial portion of the sciatic nerve formed? How does it run in comparison to the peroneal portion?
5. How is the peroneal portion of the sciatic nerve formed?
6. From what nerve roots is the pudendal nerve formed?

Answers:
1. The superior gluteal nerve is formed from the posterior part of the lumbosacral trunk (L4 and L5) and S1.
2. The posterior part of L5, S1, S2.
3. Piriformis.
4. The anterior branches of the ventral rami of L4-S3 form the tibial portion, which lies medially to the peroneal portion.
5. The posterior branches of L4-S2 joint to form the common peroneal portion of the sciatic nerve.
6. The anterior portions of S2 and S3 and part of S4.