Howship's lacuna


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Related to Howship's lacuna: Osteoclasts, osteoclastic resorption

lacuna

 [lah-ku´nah] (L.)
1. a small pit or hollow cavity.
2. a defect or gap, as in the field of vision (scotoma). adj., adj lacu´nar.
absorption lacuna resorption lacuna.
bone lacuna a small cavity within the bone matrix, containing an osteocyte, and from which slender canaliculi radiate and penetrate the adjacent lamellae to anastomose with the canaliculi of neighboring lacunae, thus forming a system of cavities interconnected by minute canals.
cartilage lacuna any of the small cavities within the cartilage matrix, containing a chondrocyte.
Howship's lacuna resorption lacuna.
intervillous lacuna one of the spaces of the placenta occupied by maternal blood, into which the fetal villi project.
osseous lacuna bone lacuna.
lacuna pharyn´gis a depression of the pharyngeal end of the eustachian tube.
resorption lacuna a pit or concavity found in bones undergoing resorption, frequently containing osteoclasts. Similar lacunae also may be found in eroding surfaces of cementum.

Howship's lacuna

A tiny pit in a living bone where osteoclasts are resorbing structural minerals and collagen.
Synonym: resorption bay; resorption lacuna
See also: lacuna