Structure of the tendon connective tissue

  • Kannus P
  • 544


    Mendeley users who have this article in their library.
  • 413


    Citations of this article.


Tendons consist of collagen (mostly type I collagen) and elastin embedded in a proteoglycan-water matrix with col-lagen accounting for 65–80% and elastin approximately 1–2% of the dry mass of the tendon. These elements are produced by tenoblasts and tenocytes, which are the elon-gated fibroblasts and fibrocytes that lie between the colla-gen fibers, and are organized in a complex hierarchical scheme to form the tendon proper. Soluble tropocollagen molecules form cross-links to create insoluble collagen molecules which then aggregate progressively into microfibrils and then into electronmicroscopically clearly visible units, the collagen fibrils. A bunch of collagen fibrils forms a collagen fiber, which is the basic unit of a tendon. A fine sheath of connective tissue called endotenon invests each collagen fiber and binds fibers together. A bunch of collagen fibers forms a primary fiber bundle, and a group of primary fiber bundles forms a secondary fiber bundle. A group of secondary fiber bundles, in turn, forms a tertiary bundle, and the tertiary bundles make up the tendon. The Macroscopic structure of tendons Tendons are anatomic structures interposed between muscles and bones transmitting the force created in the muscle to bone, and, in this way, making joint movement possible. Basically, each muscle has two tendons, proximal and distal. The point of union with a muscle is called a myotendinous junction (MTJ), and the point of union with a bone an osteotendinous junction (OTJ). The attachment of the proximal ten-don of a muscle to bone is called a muscle origin, and that of the distal tendon an insertion. Healthy tendons are brilliant white in color and fibro-elastic in texture, showing great resistance to mechanical loads. They may vary considerably in shape and in the way they are attached to bone rang-ing from wide and flat tendons to cylindrical, fan-shaped, and ribbon-shaped tendons. Muscles de-signed to create powerful, resistive forces, like the quadriceps and triceps brachii muscles, have short and broad tendons, while those that have to carry 312

Author-supplied keywords

  • Connective tissue
  • Endotenon
  • Epitenon
  • Paratenon
  • Tendon
  • Tendon fibers

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document


  • Pekka Kannus

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free