AN ANATOMICAL STUDY OF THE NERVE SUPPLY OF THE BREAST, INCLUDING THE NIPPLE AND AREOLA

There are widely differing accounts in the literature of the origin, c ourse, and distribution of the nerves to the breast and especially to the nipple and areola, This, together with our own findings at operati on, led us to investigate whether the accounts are inaccurate or the n erve supply is very variable or both. 15 breast specimens from dissect ing room cadavers, 12 female and 3 male, were dissected to study the n erve supply of the breast in detail. In the female, the breast receive d its innervation from the lateral and anterior cutaneous branches of the second to the sixth intercostal nerves and from the supraclavicula r nerves. On the lateral side in the 12 females, branches from the thi rd (9/12), fourth (12/12) and fifth (4/12), and on the medial side bra nches from the second (3/12), the third (6/12), the fourth (4/12) and the fifth (2/12) intercostal nerves were traced to a plexus under the areola, Branches from the sixth. intercostal nerve supplied the lower part of the breast but there was no direct branch to the nipple. The n erves to the nipple lay in the superficial fascia and passed through t he subdermal tissue of the areola to form a plexus under it. The exten t of the contribution by each nerve was variable, and it differed even on the left and right of the same cadaver. The nerve often described as passing through the inferolateral part of the breast to reach the n ipple is a deep branch from the anterior division of the fourth latera l cutaneous nerve, This was present in 11/12 of the female breasts but it is not the only nerve to reach the plexus under the areola as some times claimed. The male breast had a similar nerve supply but the nerv es were lying close together, whereas in a female breast they are spre ad out more widely.