Osteon Labeled Diagram – Compact Bone, Cut Across

All 9 parts on the diagram

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Start here: the osteon, 7 parts 7

Osteon The basic structural unit of compact bone. Rings of matrix around a central canal. Also called a Haversian system.
Lamellae The concentric rings of calcified matrix that make up an osteon. The singular is lamella.
Central canal The canal down the center of each osteon. It carries blood vessels, nerves and lymphatic vessels.
Lacunae Small spaces at the borders between lamellae, each holding an osteocyte. The singular is lacuna.
Osteocytes Mature bone cells, each living in a lacuna.
Canaliculi Tiny channels linking lacunae to each other and to the central canal. So nutrients reach the osteocytes and wastes leave.
Perforating canal A canal at right angles to the central canal. It carries vessels and nerves across to the periosteum and endosteum. Also called Volkmann's canal.

Around it: 2 2

Periosteum The membrane covering the outer surface of the bone.
Spongy bone Bone made of a lattice of spikes called trabeculae. Marrow lies in the spaces. Also called cancellous bone.

How this list was compiled: Read 2026-09-26. OpenStax Anatomy and Physiology 2e, section 6.3 Bone Structure, https://openstax.org/books/anatomy-and-physiology-2e/pages/6-3-bone-structure : compact bone under the periosteum; the osteon or Haversian system as its structural unit, made of concentric rings of calcified matrix called lamellae; the central (Haversian) canal with blood vessels, nerves and lymphatic vessels; perforating (Volkmann's) canals branching at right angles to reach the periosteum and endosteum; osteocytes in lacunae at the borders of adjacent lamellae; canaliculi linking lacunae with each other and the central canal for nutrients and wastes; spongy (cancellous) bone of trabeculae with red marrow in some of its spaces. Licence: own work

The drawing: Drawn for this site by script, 2026-09-26. Own work, nothing traced. Licence: own work

How it works

An osteon labeled diagram: compact bone cut across with one osteon drawn large, from its central canal out to the periosteum, and spongy bone beside it. It matches the parts asked for in: label the photomicrograph of compact bone.

Read the full guide

One osteon

An osteon is rings of matrix, the lamellae, around a central canal that carries blood vessels and nerves. Osteocytes live in lacunae between the rings, linked by tiny canaliculi. Perforating canals run across to the periosteum.

Compact and spongy

Compact bone is dense and packed with osteons. Spongy bone is a lattice of trabeculae with marrow in the spaces; it has osteocytes in lacunae too, but not in rings.

Central canals run along the bone; perforating canals run across it, at right angles.

Questions and answers

What is an osteon?

The basic structural unit of compact bone, also called a Haversian system: concentric rings of calcified matrix, the lamellae, around a central canal.

What is the difference between a lacuna and an osteocyte?

A lacuna is the small space in the bone matrix; the osteocyte is the bone cell living inside it.

What is the difference between the central canal and the perforating canal?

The central (Haversian) canal runs down the middle of each osteon. Perforating (Volkmann's) canals branch off at right angles and carry vessels and nerves across to the periosteum.