KnotesFree Orthopaedic & FRCS notes, viva stations and higher order SBAs

Osteocytes

High YieldApplied Basic SciencesthinKbox SBA

Definition

Osteocytes are mature bone cells derived from osteoblasts that become embedded within mineralised bone matrix.

Location and network

  • occupy lacunae
  • communicate through canaliculi
  • form an extensive cellular network connected by gap junctions

Functions

Mechanosensing

Osteocytes detect mechanical loading and influence bone formation and resorption in response to strain.

Regulation of remodelling

They regulate osteoblast and osteoclast activity through signalling pathways including:

  • sclerostin
  • RANKL
  • OPG-related pathways

Mineral homeostasis

Osteocytes contribute to calcium and phosphate regulation and interact with systemic hormonal pathways.

Clinical relevance

Reduced mechanical loading increases sclerostin signalling and favours bone loss. Mechanical loading suppresses sclerostin and promotes bone formation.

Diagram

Osteocytes

Written/reviewed by Kishore Puthezhath

Professor of Orthopaedics and Consultant Paediatric Orthopaedic Surgeon

FRCS (Tr & Orth) revision resource

Reviewed: September 2026