Hoffman G W, Elliott L F
Ann Surg. 1987 May;205(5):504-7. doi: 10.1097/00000658-198705000-00008.
It has previously been shown that in 62% of patients the medial pectoral nerve courses through the pectoralis minor muscle to innervate the lower half or two thirds of the pectoralis major muscle. In the other 38% of patients, the medial pectoral nerve exits around the lateral aspect of the pectoralis minor muscle. The lateral pectoral nerve courses on the undersurface of the pectoralis major muscle, innervating the proximal one third or more of the muscle. Consequently, when the pectoralis minor muscle is removed in a modified radical mastectomy, or dissection between the two muscles is performed, there is partial deinnervation of the pectoralis major muscle with partial atrophy and a decrease in size. Further, if the lateral pectoral nerve also is injured or removed, it can result in total deinnervation of the pectoralis major muscle with more severe atrophy and fibrosis of the muscle. In cosmetic augmentations, when the breast implant is placed behind the pectoralis major muscle, that muscle is partially deinnervated. In this clinical situation, this is believed to be advantageous because it allows the breast to project better. This paper details the anatomy of the pectoral nerves and discusses the clinical implications of surgery in this region as it relates to the size and function of the pectoral muscles.
先前的研究表明，62%的患者胸内侧神经穿过胸小肌，支配胸大肌的下半部分或三分之二。在另外38%的患者中，胸内侧神经在胸小肌外侧缘穿出。胸外侧神经走行于胸大肌下面，支配该肌近端三分之一或更多部分。因此，在改良根治性乳房切除术中切除胸小肌，或在两块肌肉之间进行解剖时，胸大肌会出现部分失神经支配，伴有部分萎缩和体积减小。此外，如果胸外侧神经也受到损伤或被切除，可导致胸大肌完全失神经支配，肌肉萎缩和纤维化更严重。在美容隆胸手术中，当将乳房植入物置于胸大肌后方时，该肌肉会出现部分失神经支配。在这种临床情况下，人们认为这是有利的，因为它能使乳房更好地突出。本文详细介绍了胸神经的解剖结构，并讨论了该区域手术与胸肌大小和功能相关的临床意义。
