PERIOSTEUM: CHARACTERISTICS, FUNCTIONS AND HISTOLOGY - BIOLOGY - 2025

The periosteum is a form of connective tissue that develops as a thin sheet around the bones, which it covers almost completely. It is absent in the articular ends and in sesamoid bones. It is responsible for growth, development and shaping the bones.

It is also responsible for repairing bone damage. It was discovered by a French-born researcher named Henri – Louis Duhamel du Monceau, who hypothesized that the bones grew from the periosteum; he had observed similar growth on tree trunks.

Location of the periosteum, in the layers that cover the brain. Taken and edited from: BruceBlaus. When using this image in external sources it can be cited as: Blausen.com staff (2014). "Medical gallery of Blausen Medical 2014". WikiJournal of Medicine 1 (2). DOI: 10.15347 / wjm / 2014.010. ISSN 2002-4436., from Wikimedia Commons.

The periosteum can develop some diseases such as inflammations (periostitis), reactions and benign tumors (chondromas).

characteristics

The main characteristic of the periosteum is its osteogenic capacity, that is, its ability to form bone tissue. Its size varies between 0.07 and 0.15 mm thick. Its thickness is variable, increasing towards the ends of the bones. It also varies over time, being thinner in older people.

The periosteum is a two-layer tissue. The outer layer is made up of cells called fibroblasts. The innermost layer is composed of osteogenic cells and osteoblasts, presenting nerves and being vascularized.

Features

Bone is a living tissue, its cellular components need nutrients and oxygen, as well as to release metabolic waste material. The periosteum is responsible for supplying blood to the bone, for the exchange of matter and energy.

In the early stages of life of a vertebrate organism, the periosteum participates in the development and growth of bones. The growth is given both by an increase in its length and by an increase in its thickness.

In later life, bone growth in length stops. The growth in thickness is maintained, allowing to increase the resistance to the bones.

Additionally, the periosteum is responsible for the repair of bones when fracture or other injury occurs, because it supplies the cells capable of carrying out such repairs.

Lastly, it allows other tissues to attach to the bone. These tissues include tendons, ligaments, and muscles.

Histology

The periosteum is made up of two layers, an external fibrous one and an internal one that is responsible for bone growth.

Outer or fibrous layer

It is the layer furthest from the bone. It is a layer of connective tissue. It contains fibroblasts and collagen fibers. These fibers are produced by fibroblasts.

Fibroblasts are cells derived from mesenchymal cells. They are the main cellular constituent of connective tissues, with a maximum size of 100 microns. This layer is also highly vascular and has nerve endings.

Inner or osteogenic layer

It is the innermost layer and is in contact with the bone. It contains osteogenic cells and is vascularized. Osteogenic cells can differentiate into two types of cells: osteoblasts and chondroblasts.

Osteoblasts are the cells responsible for producing the matrix of bone. As they mature, they transform into osteocytes. Chondroblasts, in turn, make the cathylaginous matrix.

Both types of cells are essential in bone growth. They also help repair bone injuries.

Diseases

Caffey disease

Caffey disease is a self-limited (self-healing) disease of the bones that has a genetic origin. It is due to a dominant genetic mutation. However, the carrier of the mutant gene sometimes does not develop the disease. It mainly affects infants.

This disease causes an unusual increase in the thickness of the bones. The main bones affected are those of the jaw, shoulder girdle, and extremities.

The first symptoms appear 150 days after birth. However, they can disappear before 24 months of age. Bones after that age tend to regain their normal thickness

Occasionally, due to abnormal growth, nearby bones have come together and do not separate again. Relapse can rarely occur several years after the first onset of the disease.

Periostitis

Periostitis is a chronic or acute inflammation of the periosteum. The causes can be trauma, stress, or infection. In the chronic form it can cause cramps, while in the acute form it can cause necropsy of the affected tissue.

Among the causes of acute periostitis are: infections of various types, such as urinary tract, chronic ulcers and autoimmune diseases.

Chronic periostitis, on the other hand, is due to stress that the bone undergoes for prolonged periods or that is repeated frequently. Athletes and people who lift a lot of weight tend to suffer from this ailment.

Periosteal chondroma

Periostal chondroma is a benign tumor that affects the periosteum. It is characterized by an unusual growth of cartilaginous tissue. It mainly affects young men. The cause of its appearance is unknown.

The most affected area is the one located between the ends (epiphysis) and the middle (diaphysis) of the humerus and femur, and the least frequent is that of the ribs. It is generally asymptomatic.

Occasionally, pain or increased tenderness may occur in the area near the tumor. The tumor does not tend to spread to other areas, but it can continue to grow where it appeared.

Treatment, in the absence of pain, is simply to monitor the tumor. If necessary, the tumor is removed by surgery.

Ewing periosteal sarcoma

Ewing's sarcoma is a malignant bone tumor. It mainly affects the cavity of the bone marrow. However, there is a very rare form of this tumor that affects the multipotential cells of the periosteum.

It mainly affects male patients over 20 years of age. The main bone involved with this condition is the femur. Treatment consists of chemotherapy or radiation therapy, plus removal of the tumor.

Typical and less typical places, where Ewing's Sarcoma can appear. Taken and recovered from: Frank Gaillard, via Wikimedia Commons.

Medical applications

Periosteal transplantation has been used with varying levels of success to treat different bone ailments. It is generally used after culture in media enriched with growth factors and modulators of bone formation.

It has been used in craniofacial reconstruction, as well as for the reconstruction of dental alveoli. Also to avoid amputations in cases of pseudoarthrosis.

It has been used experimentally in animals to improve tendon healing. However, some results are contradictory and deterioration of new bone tissue over time has been suggested.

References

1. IL Aymoré, W. Meohas, ALB Almeida, D. Proebstner (2005), Periosteal Ewing's sarcoma: case report and literature review. Clinical Orthopedics and Related Research.
2. C. Hall (2001). Caffey disease. Orphanet. Recovered from www.orpha.net.
3. JK Kealy, H. McAllister, JP Graham (2011). Diagnostic radiology and ultrasonography of the dog and cat, 5th edition. Elsevier, Canada.
4. M.Pajares-López, P. Hernández-Cortés (2005). Periosteal application in an experimental model of tendon healing in rabbit. Journal of Orthopedics and Traumatology.
5. Periosteal Chondroma. Chindren's hospital of Philadelphia. Retrieved from www.chop.edu.
6. Periosteum. Recovered from en.wikipedia.org.
7. AL Sesman-Bernal, JA León-Pérez, G. Fernández-Sobrino (2007), News in cranial bone regeneration and remodeling. Literature review. Acta Pediátrica Mexicana.