The coccygeal glomus (coccygeal gland or body; Luschka’s gland) is a

vestigial structure Vestigiality is the retention, during the process of evolution, of genetically determined structures or attributes that have lost some or all of the ancestral function in a given species. Assessment of the vestigiality must generally rely on co ...

placed in front of, or immediately below, the tip of the

coccyx The coccyx ( : coccyges or coccyxes), commonly referred to as the tailbone, is the final segment of the vertebral column in all apes, and analogous structures in certain other mammals such as horses. In tailless primates (e.g. humans and othe ...

Anatomy

It is about 2.5 mm. in diameter and is irregularly oval in shape; several smaller nodules are found around or near the main mass. It consists of irregular masses of round or polyhedral cells epitheloid cells, which are grouped around a dilated

sinusoidal A sine wave, sinusoidal wave, or just sinusoid is a mathematical curve defined in terms of the '' sine'' trigonometric function, of which it is the graph. It is a type of continuous wave and also a smooth periodic function. It occurs often in m ...

capillary vessel. Each cell contains a large round or oval nucleus, the

protoplasm Protoplasm (; ) is the living part of a cell that is surrounded by a plasma membrane. It is a mixture of small molecules such as ions, monosaccharides, amino acid, and macromolecules such as proteins, polysaccharides, lipids, etc. In some defini ...

surrounding which is clear, and is not stained by chromic salts. Since it is not stained by chromic salts, it is not truly a part of Chromafin system; viz. the system which includes cells stained by chromic salts, consisting of renal medulla, para ganglia, and para aortic bodies. It is situated near the ganglion impar in pelvis, and also at the termination of

median sacral artery The median sacral artery (or middle sacral artery) is a small artery that arises posterior to the abdominal aorta and superior to its bifurcation. Structure The median sacral artery arises from the abdominal aorta at the level of the bottom qu ...

Clinical significance

It may appear similar to a

glomus tumor :''Glomus tumor was also the name formerly (and incorrectly) used for a tumor now called a paraganglioma.'' A glomus tumor (also known as a "solitary glomus tumor," "solid glomus tumor,") is a rare neoplasm arising from the glomus body and mainly ...

References

Human anatomy {{Anatomy-stub