FUNCTIONAL AND CLINICAL ANATOMY OF THE POSTERIOR INSERTION OF THE HUMAN VOCAL LIGAMENT

The suggested methods of the formation of intubation granuloma as well as carcinoma invasion in the area of posterior vocal ligament inserti on have been controversial. One reason for divergent opinions is possi bly based on different judgments of morphology in this region. The pre sent study analyzed structures of the vocal ligament and vocalis muscl e insertion at the vocal process by means of histological, immunohisto chemical and electron microscopic methods. Investigations were perform ed in three planes on the vocal cords of 22 men and 19 women (aged 21- 97 years). Inside the insertion zone of the vocal ligament at the voca l process three structures could be distinguished: hyaline cartilage a t the base of arytenoid cartilage, elastic cartilage at its apex and t he posterior elastic nodule in front of them. No perichondrium could b e seen around the elastic nodule. In elastic nodules type I and type I II collagen fibrils as well as elastic fibers formed a scissorlike mes hwork around large fibroblasts. The vocalis muscle inserted at the per ichondrium in the lateral part of the arytenoid skeleton by short tend ons. At the insertion zone blood vessels of the vocalis muscle penetra ted the perichondrium and reached the cartilaginous matrix. At the beg inning of osteogenesis, the blood vessels connected with intraosseous blood vessels of the arytenoid. Connective tissue cells of the inserti on zone and extracellular matrix components formed by these cells fulf illed a biomechanical function by equalizing the different elastic mod uli of tendon, cartilage or bone. The lack of perichondrium around the lengthened posterior elastic nodule made formation of intubation gran ulomas caused by perichondritis in this area impossible. Loosened peri chondrium or periosteum in the area of the insertion of the vocalis mu scle at the vocal process, ossification and associated vascularization of the arytenoid skeleton permitted invasion of carcinomas into the a rytenoid.