Sharpey's fibres (bone fibres, or perforating fibres) are a

matrix Matrix most commonly refers to: * ''The Matrix'' (franchise), an American media franchise ** ''The Matrix'', a 1999 science-fiction action film ** "The Matrix", a fictional setting, a virtual reality environment, within ''The Matrix'' (franchis ...

connective tissue Connective tissue is one of the four primary types of animal tissue, along with epithelial tissue, muscle tissue, and nervous tissue. It develops from the mesenchyme derived from the mesoderm the middle embryonic germ layer. Connective tiss ...

consisting of bundles of strong predominantly type I collagen fibres connecting

periosteum The periosteum is a membrane that covers the outer surface of all bones, except at the articular surfaces (i.e. the parts within a joint space) of long bones. Endosteum lines the inner surface of the medullary cavity of all long bones. Structure ...

bone A bone is a Stiffness, rigid Organ (biology), organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red blood cell, red and white blood cells, store minerals, provid ...

. They are part of the outer fibrous layer of periosteum, entering into the outer circumferential and interstitial

lamellae Lamella (plural lamellae) means a small plate or flake in Latin, and in English may refer to: Biology * Lamella (mycology), a papery rib beneath a mushroom cap * Lamella (botany) * Lamella (surface anatomy), a plate-like structure in an animal * ...

of bone tissue. Sharpey's fibres are also used to attach muscle to the periosteum of bone by merging with the fibrous periosteum and underlying bone as well. A good example is the attachment of the

rotator cuff The rotator cuff is a group of muscles and their tendons that act to stabilize the human shoulder and allow for its extensive range of motion. Of the seven scapulohumeral muscles, four make up the rotator cuff. The four muscles are the supraspi ...

muscles to the blade of the

scapula The scapula (plural scapulae or scapulas), also known as the shoulder blade, is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like their connected bones, the scapulae are paired, with each scapula on eithe ...

. In the

teeth A tooth ( : teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, tear ...

, Sharpey's fibres are the terminal ends of principal fibres (of the periodontal ligament) that insert into the

cementum Cementum is a specialized calcified substance covering the root of a tooth. The cementum is the part of the periodontium that attaches the teeth to the alveolar bone by anchoring the periodontal ligament.Illustrated Dental Embryology, Histology, a ...

and into the periosteum of the alveolar bone. A study on rats suggests that the three-dimensional structure of Sharpey's fibres intensifies the continuity between the

periodontal ligament The periodontal ligament, commonly abbreviated as the PDL, is a group of specialized connective tissue fibers that essentially attach a tooth to the alveolar bone within which it sits. It inserts into root cementum one side and onto alveolar b ...

fibre and the

alveolar Alveolus (; pl. alveoli, adj. alveolar) is a general anatomical term for a concave cavity or pit. Uses in anatomy and zoology * Pulmonary alveolus, an air sac in the lungs ** Alveolar cell or pneumocyte ** Alveolar duct ** Alveolar macrophage * ...

bone (tooth socket), and acts as a buffer medium against stress. Sharpey's fibres in the primary acellular cementum are mineralized fully; those in cellular cementum and bone are mineralized only partially at their periphery. In the

skull The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, the ...

the main function of Sharpey's fibres is to bind the cranial bones in a firm but moveable manner; they are most numerous in areas where the bones are subjected to the greatest forces of separation. In the spine, similar fibres join the

intervertebral disc An intervertebral disc (or intervertebral fibrocartilage) lies between adjacent vertebrae in the vertebral column. Each disc forms a fibrocartilaginous joint (a symphysis), to allow slight movement of the vertebrae, to act as a ligament to hold t ...

to the adjacent vertebrae. Each fibre is accompanied by an

arteriole An arteriole is a small-diameter blood vessel in the microcirculation that extends and branches out from an artery and leads to capillaries. Arterioles have muscular walls (usually only one to two layers of smooth muscle cells) and are the primar ...

and one or more

nerve fibre An axon (from Greek ἄξων ''áxōn'', axis), or nerve fiber (or nerve fibre: see spelling differences), is a long, slender projection of a nerve cell, or neuron, in vertebrates, that typically conducts electrical impulses known as action po ...

s. Scottish anatomist

William Sharpey William Sharpey FRS FRSE LLD (1 April 1802 – 11 April 1880) was a Scottish anatomist and physiologist. Sharpey became the outstanding exponent of experimental biology and is described as the "father of British physiology". Early life Sharpe ...

described them in 1846, although they were also referred to as the claviculi of Gagliardi after

Domenico Gagliardi Domenico Gagliardi (c. 1660 – c. 1735) was an Italian physician and anatomist. He may have served as a professor of anatomy at Rome (but his name is not listed) and served as chief physician (protomedicus) to four Popes. He studied the structure ...

who described them in 1689.

References

{{Bone and cartilage Musculoskeletal system