Here are some lecture drawings created for our discussion of the muscles of the rear.
If you need me repeat the function, origin, and insertion of each of these muscles, just leave me a comment. Remember the muscle pulls in to its origin. The bone, or system attached at insertion gets pulled.
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Skeleton visual starting point.
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The top layer muscles are shown isolated and identified.
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As they would appear without the skin, note the stretch and compression on either side.
Anterior is to come, hang on.
Let me know if you're looking for a detail.