In addition to the pudendal nerve, which nerve supplies motor fibres directly to the levator ani and coccygeus muscles from above the pelvic floor?

• A Nerve to obturator internus (L5, S1)
• B Pelvic splanchnic nerves (S2, S3, S4)
• C Nerve to levator ani arising from S3 and S4 ventral rami ✓
• D Inferior gluteal nerve (L5, S1, S2)

Explanation

The levator ani and coccygeus receive dual innervation: the pudendal nerve from below, and the direct nerve to levator ani from the ventral rami of S3 and S4 on the pelvic surface of the muscle. The pelvic splanchnic nerves are purely parasympathetic and supply viscera, not skeletal muscle. The nerve to obturator internus enters the gluteal region and never reaches the pelvic floor.

Reference: Gray's Anatomy for Students, 4th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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