What Is a Tendon Cell?

A tendon cell is a specialized type of connective tissue found in the tendons that attach muscles to the bone. These cells secrete components of the extracellular matrix used to support the tendons and stabilize them, making them extremely tough and capable of withstanding high strain. Understanding how such cells differentiate in embryonic development and grow after birth can be important for treating people with connective tissue disorders and tendon injuries such as strains and separations.

The structure of a tendon cell is elongated; the cells are organized very tightly within each tendon, surrounded by a matrix of proteins they secrete. Also called tenocytes, they are involved in the production and turnover of new tendon cells as well as the creation of more extracellular matrix. Growth can be stimulated by injuries as well as athletic activity, which tends to increase muscle and tendon development. As people grow stronger, their muscle attachments must compensate by increasing in size and density.

Like other cells in the body, a tendon cell can use a variety of cell signaling pathways to regulate its own activity as well as that of neighboring cells. They can pass messages to each other to trigger growth, temporary dormancy, and other responses to the environment. These cells are also involved in muscle relaxation and contraction to control movement, requiring coordinated responses to signaling from nerve cells that interact with skeletal muscles and tendons.

Research on tendon cell growth is a subject of interest for physicians who work with the musculoskeletal system. The possibility of promoting healing and new growth can be important for treating injuries, particularly severe athletic injuries that may make it difficult to return to the playing field. Snapped and severely strained tendons can end careers, even with excellent medical care, and new methods of treatment offer opportunities to athletes. Studies evaluate the structure and composition of the tendons as well as the processes involved in regulating cell growth and differentiation.

Patients with connective tissue disorders may have tendon cell problems. These cells may fail to develop properly or could grow more slowly than usual, increasing the risk of tendon injuries or creating problems with specific muscle attachments. Activities like physical therapy can help promote strength and flexibility, but must be undertaken with care in order to protect the patient’s health. Research to stimulate connective tissue growth, correct deficiencies in the extracellular matrix, and increase muscle strength can help such patients.