The inferior gluteal nerve often has a cutaneous branch: A discovery with application to hip surgery and targeting gluteal pain syndromes.
Clin Anat. 2018 Sep;31(6):937-941. doi: 10.1002/ca.23232. Epub 2018 Oct 18.
Iwanaga J, Simonds E, Vetter M, Patel M, Oskouian RJ, Tubbs RS.
Abstract
The inferior gluteal nerve has been traditionally described as a solely motor branch innervating the gluteus maximus. However, during routine dissection of the gluteal region, a cutaneous branch of the inferior gluteal nerve was identified. As the gluteal region is vulnerable to the development of pressure ulcers and iatrogenic injury with for example, surgical approaches and injection therapies, a comprehensive understanding of its cutaneous innervation is important. Therefore, the aim of this study was to elucidate the anatomy of this cutaneous branch of the inferior gluteal nerve in a series of cadavers. Twelve sides from six fresh-frozen cadaveric specimens were dissected. When a cutaneous branch was identified piercing the gluteus maximus, its origin from the inferior gluteal nerve was verified and the diameter and length of it measured. Additionally, for localization, the distance from the midline to the exit point of the cutaneous branch from the gluteus maximus was measured. One to two cutaneous branches were identified as arising from the inferior gluteal nerve on nine sides (75%). The branch(es) were usually located in the lower outer quadrant of the gluteus maximus. These branches had a mean distance of 12.5 cm from the midline. Their mean diameter and length was 0.7 mm and 28.6 cm, respectively. On all sides with a cutaneous branch of the inferior gluteal nerve, the skin over the posterior aspect of the greater trochanter was innervated by superior and inferior cluneal nerves and supplemented by cutaneous branch(es) of the inferior gluteal nerve. Side or sex was not a predictor of the presence of a cutaneous branch of the inferior gluteal nerve. To our knowledge, a cutaneous branch derived from the inferior gluteal nerve has not been previously described. Based on our cadaveric findings, the majority of individuals will have the area of skin over the greater trochanter innervated by this nerve. Therefore, surgeons and pain specialists should be aware of its presence and might develop surgical procedures that help avoid it or develop technical advances that target it for various pain syndromes in this area. We propose naming these cutaneous branches the lateral cluneal nerves, which would necessitate renaming the middle cluneal nerves to medial cluneal nerves. Clin. Anat. 31:937-941, 2018.
© 2018 Wiley Periodicals, Inc.
KEYWORDS:
gluteus maximus; hip joint; inferior gluteal nerve; posterior approach