Avaliação histomorfométrica dos mecanorreceptores e terminações nervosas livres nos ligamentos laterais do tornozelo aplicada no estresse fisiológico

Abstract

Microscopic examination of different tissues is widely used to evaluate the morphology of biological structures. When joint components such as capsules, ligaments and muscles are submitted to mechanic stress and pain, free nerves endings and mechanoreceptors located within these anatomical structures detect and relay this physiological information to the central nervous system. Ankle lateral ligaments (anterior talofibular, talocalcaneal and posterior talofibular) obtained from 24 ankles of 13 masculine non-formolized unclaimed cadavers were used in the study. Age ranged from 18 to 65 years (mean age: 41,6 years). Ligaments samples were divided into 3 equal parts (proximal, central and distal segments). Following tissue impregnation with gold chloride 1% solution, serial cuts (20µ thickness) were studied under light microscopy. Mechanoreceptors (Rufini, Pacini and Golgi) and free nervous endings were identified, according to Freeman and Wike’s classification. Counting of individual mechanoreceptors and free nerves endings (histomorphometry) and evaluation of mechanoreceptor density in squared millimeter areas was carried out in all samples. There was a significant prevalence of Pacini (p<0.001) compared with Rufini and Golgi mechanoreceptors types. However, there was no significant difference in mechanoreceptors density in the different tendon segments analyzed (p>0.05).