RESUMO
PURPOSE: To increase our understanding of the mechanism of pain and the sensation of wrist instability by studying the distribution of the mechanoreceptors in the triangular fibrocartilage (TFC). METHODS: The distribution and density of the nerve endings were investigated in 34 TFC specimens obtained from human cadavers. We studied the dorsal, palmar, ulnar, radial, and central areas after staining by a modified gold chloride technique. RESULTS: The free nerve endings, responsible for sensing pain, predominate in the ulnar and dorsal areas. The Vater-Pacini corpuscles predominate in the radial and dorsal area, promoting perception of the onset or cessation of movement and mechanical stress change. The Golgi-Mazzoni corpuscles were more frequent in the ulnar and ventral areas, linking these areas to function of slow adaptation and sensation of extreme movements. The proprioceptive function receptors were found in all areas of TFC because Ruffini corpuscles have homogeneous distribution in this fibrocartilaginous tissue. CONCLUSIONS: Our results showed that the nerve endings were distributed at the periphery of TFC and showed different concentrations of each type of mechanoreceptors per topographic area, suggesting that they play specific roles in the proprioceptive and nociceptive reflexes of the wrist.
Assuntos
Cartilagem Articular/inervação , Mecanorreceptores/ultraestrutura , Terminações Nervosas/ultraestrutura , Punho/anatomia & histologia , Punho/inervação , Adolescente , Adulto , Idoso , Cadáver , Cartilagem Articular/citologia , Humanos , Pessoa de Meia-Idade , Coloração e RotulagemRESUMO
The innervation of the articular disc of the temporomandibular joint of 6 adults guinea pigs was studied with the use of Nonidez technique. Only occasional nerve fibers next to blood vessels at the posterior inferior peripheral part of the articular disc were observed.