TENDON (from ME. tent/o, tendon, from Lat. tendere. to stretch, extend). A term em ployed in anatomy to desig,nate the structure of white fibrous tissue reaching from the end of a muscle to bone or some other structure which is to serve as a fixed attachment for it, or which it is intended to move. In accordance with their form, tendons have been divided into the three following varieties: (1) Funicular, or rope-like, as the long tendon of the biceps muscle of the arm: (2) fascicular, as the short tendon of that muscle, and as most tendons generally: and (3) aponeurotic, or tendinous expansions, sometimes of considerable extent, and serviceable in strengthening the walls of cavities, as, for ex ample, the tendons of the abdominal muscles.
The tendons begin by separate fasciculi from the end of each muscular fibre. and they similarly terminate by separate fasciculi in distinct depres sions in the bones besides being closely incor porated with the periosteum. Tendons, to
gether with their sheaths, are subject to acute and chronic inflammations and to tumor formation. The ordinary acute form of inflammation known as acute teno-synoritis is usually brought along by injury such as a blow or by over-use. The chronic form of inflamma tion is usually tubercular, though a rheumatic diathesis sometimes occurs. The tumors usually observed in tendons are small fibres and cartila ginous enlargements. Such growths occasionally assume malignant character. When separation of a tendon occurs either by rupture or incision, if the ends of the divided tendon 'are not too widely separated, repair takes place by the depo sition of new fibrous tissue, closely resembling true tendon tissue. This repair is usually com plete at the end of three weeks.