Pourquoi les doigts craquent? Deux chercheurs apportent la réponse


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Ce n’était jusque-là qu’une hypothèse. Des scientifiques confirment maintenant: le bruit des doigts qui craquent (ou que l’on fait craquer) ne provient pas des os, mais de bulles microscopiques dans le liquide des articulations des doigts.


Abdul Barakat, professeur à l’Ecole polytechnique et l’un de ses élèves ont publié jeudi 29 dans la revue Scientific Reports (voir ici) le modèle mécanique expliquant ce bruit. Des conclusions qui ont nécessité un an et demi de travail et l’étude des bruits des doigts qui craquent enregistrés dans une chambre acoustique.


Voici, en résumé, la conclusion de ces travaux: quand les doigts sont étirés ou comprimés, une petite dépression se forme dans le liquide synovial, le lubrifiant naturel présent entre nos articulations. Or, quand l’articulation revient à sa place, la bulle qui est ainsi mise sous pression se met à brusquement éclater et produit alors le bruit du craquement des doigts.



Voir aussi – Rhumatismes: un Français sur deux souffre de douleurs articulaires 



Les deux scientifiques ne sont pas penchés cependant sur l’autre question du craquement des doigts: est-ce une pratique dangereuse pour la santé? Cette manie a en effet été soupçonnée de provoquer de l’arthrite. En 2009, un médecin avait démontré qu’il n’y avait aucun lien entre les deux malgré es recherches statistiques laissant entendre qu’une causalité existait. Les deux scientifiques qui ont prouvé scientifiquement les causes du craquement des doigts ne se prononcent pas sur ce point.


Article source: http://www.cbc.ca/sports/olympics/winter/hockey/spengler-cup-canada-final-recap-1.4468740?cmp=rss


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