The sciatic nerve, however, is both the longest and largest nerve in the human body. These anatomical variations can vary from person to person.

1.In some persons, the sciatic nerve passes above the piriformis muscle.

2. While in some people, the nerve passes below the piriformis muscle.

3. Sometimes, the sciatic nerve may be divided and pass above or below the piriformis muscles.

4. Sometimes, the nerve splits in two parts above the piriformis muscles, one passes through the piriformis and the other passes below it. This version is the most popular.

5. Sometimes in individuals, the nerve remains undivided, and it passes alone through the piriformis muscle.

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