Experimental study on repair of lacerated tendons.

The distribution of intratendinous vessels of the flexor tendon of chickens was observed by microangiography using the ink injection method, and it was confirmed that the distribution was similar to that in man. Semi-tranverse excision of the tendon was performed at a site with an abundance of vessels and to healing process was observed in four groups classified as follows: Those in which the tendon sheath was intact, those in which it was excised, those in which circulation was intact and those in which it was obstructed. In the sheath and circulation intact groups; the endotenon was found to primarily fill the gap at the site of lacertion, there was no thickening of the tendon and the tendon was restored to normal ealier. However, in the sheath excised and circulation obstructed groups, there was excessive proliferation of the epitenon, generalized thickening of the tendon and although there was filling of the gap with epitenons, maturation of granulation tissue was markedly delayed. Thus, it was learned that intratendinous circulation is highly important for healing of the tendon. Therefore, a study was undertaken to observe microangiographically the effects on intratendinous vessels of such tendon suture procedures as the Bunnell Method, the Modified Kessler Method and Tsuge Method. Results revealed that the Tsuge Method did not injure the intratendinous vessels, and thus was considered to be one of the outstanding tendon suture procedures. 417 INTRODUCTION placed upon the development of improvement in the techniques8>. Generally, the objective of treatmer:t of injuried tendons is to preve:r:.t adhesion between the sutured site of the tendon and surrounding tissue so that normal gliding of the sutured tendon can be obtained. However, it is well known that the degree of adhesion is dei=endent upon such things as the type of injury, treatment administered to the sheath, tendon suture procedure and length of postoperative immobilization. According to Matthews17>, adhesion can be prevented or limited to the minimum by one or a combination of two of the following excision of the synovial sheath, tendon suture (Bunnell Method) and immobilization, but when all three are combined, strong adhesion develops. However, these three procedures are indispensable in the treatment of injured tendons, and thus at present, hope is being On the other hand, various experimental studies are being made in the area of tendon tissue rerair. Pote1za (1962) 22 > claims that injury of the tendon is repaired by fibroblasts derived from the surrounding tissue cannot be avoided. However, according to Lindsay (1960) >, the te:idon tissue has an intrinsic potential for repair, and that cells of the epitenon and endote~1on layers play this role. Subsequently, there have been many reports supporting the latter theJry5• 10 • 16• 20 • 24•27>. At preser:t, it has bee~1 confirmed that the tendon tissue defiEitely possesses intrinsic potential for rei::air so long as it has an adequate supply of nourishment. Futher, the intra-tendinous vessels and diffusion of synovial fluid through the sheath have been found to be two such nutrie::it supi::ly routes •