Superficial branch of perineal nerve
Ramus superficialis nervi perinealis
Definition
The superficial branch of perineal nerve provides sensory innervation to the skin of the perineum and the posterior part of scrotum or the labium majus.
The superficial branch is one of the terminal offshoots of the perineal nerve. The perineal nerve, as you may know, is a branch of the pudendal nerve. The latter winds around the ischial spine and sacrospinous ligament to enter the perineal region, where it divides into three branches, including the perineal nerve, dorsal nerve of penis/clitoris, and inferior rectal nerve. The perineal nerve further ends up dividing into superficial and deep branches.
The superficial branch of perineal nerve contain various neuronal fibers which transmit general somatic sensations from 1) the perineal skin, 2) the posterior scrotal skin (a.k.a. posterior scrotal nerve, in men) or posterior part of labium majus (a.k.a. posterior labial nerve, in women).
Please note that, unlike the superficial branch of perineal nerve, the deep branch lacks cutaneous innervates and only innervates muscles in the perineal region.
References
Text written by Muhammad A. Javaid, MD, PhD © 2022 IMAIOS.
Drake, R.L., Vogl, A.W. and Mitchell, A.W.M. (2009). ‘Chapter 5: Pelvis’ in Gray’s anatomy for Students. (2nd ed.) Philadelphia PA 19103-2899: Elsevier, pp. 490-491.
Rea, P. (2015). ‘Chapter 3: Lower Limb Nerve Supply’ in Essential Clinically Applied Anatomy of the Peripheral Nervous System in the Limbs. Editor(s): Rea, P. Academic Press University of Glasgow, Glasgow, UK, pp. 101-177. https://doi.org/10.1016/B978-0-12-803062-2.00003-6
Kinter, K.J. and Newton, B.W. Anatomy, Abdomen and Pelvis, Pudendal Nerve. [Updated 2022 Sep 12]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK554736/
