第三节　层次结构

图312 背部的肌肉和皮神经1
Muscles and cutaneous nerves of the back 1

图313 背部的肌肉和皮神经2
Muscles and cutaneous nerves of the back 2

图314 枕下三角
Suboccipital triangle

图315 腰上三角和腰下三角
Superior lumbar triangle and inferior lumbar triangle

图316 背固有肌
Intrinsic back muscles

图317 腰肌（后面观）
Lumbar muscles (posterior aspect)