Contraction Of The Cremaster Muscles

Cremaster musculus

Writer: Roberto Grujičić MD • Reviewer: Jana Vasković MD
Last reviewed: July 06, 2022
Reading fourth dimension: five minutes

Cremaster is a paired muscle of the pelvis and perineum that is fully developed only in the external genitalia of males. Being located between the internal and external layers of spermatic fascia, cremaster covers the testes and spermatic cord. Some remnants of the muscle are also present in women, located next to the ligaments of the uterus.

By contracting, the cremaster muscle pulls the testes superiorly (retraction) towards the inguinal canal. This action protects the testes and sperm cells from the negative ecology factors (e.g. extreme temperature changes).

Fundamental facts about the cremaster muscle
Origin	Lateral part: Lower edge of internal abdominal oblique and transversus abdominis muscles, inguinal ligament Medial part: Pubic tubercle, lateral part of pubic crest
Insertion	Tunica vaginalis of testis
Action	Retraction of testis
Innervation	Genital co-operative of genitofemoral nerve (L1, L2)
Claret supply	Cremasteric branch of inferior epigastric artery

In this article, we will discuss the anatomy and function of the cremaster muscle.

Contents

Construction
Origin and insertion
Relations
Innervation
Blood supply
Role
1. Cremasteric reflex
Sources

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Structure

The detailed structure of the cremaster musculus is yet to be adamant. Co-ordinate to the majority of anatomical literature, the cremaster muscle is considered as a striated muscle. Notwithstanding, contempo studies on the homo cadavers signal that this muscle contains a large number of smooth muscle fibers that are organized in the muscle bundles and dispersed betwixt the striated muscle fibers.

Further histological studies also institute that some nerve endings and plexuses interlace with these musculus fibers. Along with the genitofemoral nerve, these nerve endings and plexuses are suggested to provide boosted autonomic innervation for this muscle.

Origin and insertion

The cremaster muscle consists of two parts; lateral and medial. The lateral part of cremaster is mainly derived from the lower fibers of the transversus abdominis muscle or from the internal abdominal oblique muscle and inguinal ligament.

Variable and occasionally absent-minded, the medial role of the muscle originates from the pubic tubercle and lateral part of the pubic crest. The medial fibers fuse with the lateral ones and pass inferiorly, covering the spermatic cord. Upon entering the scrotum, cremaster forms a sparse network of muscle fascicles that insert onto the inferior aspect of tunica vaginalis, a serous membrane that covers the testes.

Relations

The cremasteric muscle fibers unite with the surrounding loose connective tissue to comprise a thin roofing for the spermatic string known as the cremasteric fascia. It extends through the scrotum and around the testis, existence situated deep to the external spermatic fascia.

The cremasteric artery and vein and genital branch of genitofemoral nerve are located betwixt the external spermatic fascia and cremasteric fascia.
Since the internal ballocks of women don't crave the protective role of cremaster as they are placed within the body, this muscle in women is not fully developed. Some remnants of the muscle are in fact present near the distal portion of the round ligament of uterus.

Explore this written report unit to find more than articles, videos and quizzes to learn everything virtually the office of cremaster within male reproductive system.

Innervation

Cremaster is innervated by sympathetic and somatic fibers of the genital co-operative of genitofemoral nerve (L1, L2).

Blood supply

Cremaster is supplied by the cremasteric artery, a branch of inferior epigastric artery.

Function

Cremasteric reflex

The main action of the cremaster muscle is to pull the testes superiorly towards the superficial inguinal ring. This involuntary action is known as the cremasteric reflex, and its function is to bring the testes closer to the warm surround of the body when they are exposed to the low exterior temperatures.

The cremasteric reflex tin can exist provoked and tested by stroking the pare of the medial aspect of the thigh as well equally applying cold stimuli in the same location. This stimulates the ilioinguinal nerve, which consequently activates the genital co-operative of genitofemoral nervus that innervates and activates the muscle. This reflex protects the testes from severe temperature changes, adjusting the temperature inside them for acceptable sperm production.

Sources

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References:

Moore, M. Fifty., Dalley, A. F., & Agur, A. M. R. (2014). Clinically Oriented Anatomy (7th ed.). Philadelphia, PA: Lippincott Williams & Wilkins.
Palastanga, Due north., & Soames, R. (2012). Anatomy and homo movement: structure and role (sixth ed.). Edinburgh: Churchill Livingstone.
Standring, S. (2016). Gray's Beefcake (41tst ed.). Edinburgh: Elsevier Churchill Livingstone.
Netter, F. (2014). Atlas of Human Anatomy (6th ed.). Philadelphia, PA: Saunders.
Kayalioglu, G., Altay, B., Uyaroglu, F.G., Bademkiran, F., Uludag, B. and Ertekin, C. (2008), Morphology and Innervation of the Homo Cremaster Muscle in Relation to its Function. Anat Rec, 291: 790-796.

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