Related Experiment Video
Updated: Aug 10, 2026
07:10
A Sectioning, Coring, and Image Processing Guide for High-Throughput Cortical Bone Sample Procurement and Analysis for Synchrotron Micro-CT
Published on: June 12, 2020
A model of osteon closure in cortical bone
1Institut für Genetik und für Toxikologie von Spaltstoffen, Kernforschungszentrum Karlsruhe, Federal Republic of Germany.
Calcified Tissue International
|November 1, 1990
Summary
This study presents a new model for osteon closure, detailing how osteoblast activity changes during bone remodeling. The findings reveal a consistent decrease in osteoblast activity in humans and dogs during osteon closure.
Area of Science:
- Biomaterials Science
- Skeletal Biology
- Computational Biology
Background:
- Cortical bone remodeling is a complex process involving osteoblasts and osteocytes.
- Understanding osteon closure dynamics is crucial for skeletal health research.
Purpose of the Study:
- To develop and present a computational model for osteon closure.
- To incorporate physiological aspects of bone remodeling into the model.
- To analyze the kinetics of osteon radial closure.
Main Methods:
- Development of a simplified model with constant osteoblast activity.
- Creation of an extended model with variable osteoblast activity, based on Lee's law.
- Utilizing the extended model to calculate dynamic changes during osteon closure.
Main Results:
- Osteoblast activity steadily decreases during osteon radial closure in both humans and beagle dogs.
- The model calculates dynamic changes in the closing cone's geometrical shape.
- Time-dependent changes in osteoid seam width, osteoblast number, and bone formation rate were determined.
Conclusions:
- The presented model accurately reflects physiological features of cortical bone remodeling.
- The extended model provides insights into the variable nature of osteoblast activity during osteon closure.
- The model's potential is demonstrated through calculations of dynamic geometric and cellular changes in the closing cone.
Related Concept Videos
01:31Osteoclasts in Bone Remodeling
Osteoclasts are cells responsible for bone resorption and remodeling. They originate from hematopoietic progenitor cells present in the bone marrow. Numerous progenitor cells fuse to form multinucleated cells, each with 10-20 nuclei. A single osteoclast has a diameter of 150 to 200 µM. These cells have ruffled borders that break down the underlying bone tissue and release minerals such as calcium into the blood in bone resorption. Osteoclasts cling to bones with their ruffled edges during bone...
01:17Gross Anatomy of Bone
The two main features of a long bone are the diaphysis and the epiphysis.
The diaphysis is the tubular shaft that runs between the proximal and distal ends of the bone. The walls of the diaphysis are composed of dense and hard compact bone made of numerous osteons — the functional unit of the compact bone. The hollow region in the diaphysis is called the medullary cavity, which harbors the bone marrow. In infants and children, this marrow cavity is filled with red marrow, whereas in adults, it...
The diaphysis is the tubular shaft that runs between the proximal and distal ends of the bone. The walls of the diaphysis are composed of dense and hard compact bone made of numerous osteons — the functional unit of the compact bone. The hollow region in the diaphysis is called the medullary cavity, which harbors the bone marrow. In infants and children, this marrow cavity is filled with red marrow, whereas in adults, it...
01:27Compact Bone
Most bones contain compact and spongy osseous tissue, but their distribution and concentration vary based on the bone's overall function.
Compact bone, also called cortical bone, is the denser, stronger of the two types of bone tissue. It is found under the periosteum and in the diaphyses of long bones, where it provides support and protection. The microscopic structural unit of compact bone is called an osteon, or haversian system. Each osteon is composed of concentric rings of calcified...
Compact bone, also called cortical bone, is the denser, stronger of the two types of bone tissue. It is found under the periosteum and in the diaphyses of long bones, where it provides support and protection. The microscopic structural unit of compact bone is called an osteon, or haversian system. Each osteon is composed of concentric rings of calcified...
01:29Bone Formation by Intramembranous Ossification
Intramembranous ossification is one of the two processes involved in the development of bones within an embryo. The flat bones of the face, most of the cranial bones, and the clavicles are formed via this process. During intramembranous ossification, the bones develop directly from sheets of undifferentiated mesenchymal connective tissue.
The process begins when mesenchymal cells in the embryonic skeleton gather together and differentiate into osteogenic cells, which then develop into...
The process begins when mesenchymal cells in the embryonic skeleton gather together and differentiate into osteogenic cells, which then develop into...
01:09Spongy Bone
All bones comprise an outer layer of compact bone, and an interior made up of spongy bone tissue, also called cancellous or trabecular bone. In long bones, spongy bone tissue is mainly found in the interior of the epiphyses (broad ends of the bone).
Spongy bone is more porous, and less dense compared to compact bone. It is composed of concentric lamellae that are arranged irregularly to form the trabecular network. In some bones, the spaces between trabeculae contain red marrow, where...
Spongy bone is more porous, and less dense compared to compact bone. It is composed of concentric lamellae that are arranged irregularly to form the trabecular network. In some bones, the spaces between trabeculae contain red marrow, where...
01:24Bone Formation by Endochondral Ossification
Bone formation, or ossification, begins around the sixth to seventh week of embryonic development. Most bones develop from a cartilaginous template through the process of endochondral ossification. Cartilage formation begins when clusters of mesenchymal cells differentiate into chondrocytes. These chondrocytes proliferate rapidly and secrete an extracellular matrix that becomes encased in a membrane called the perichondrium. The resulting cartilage model provides a template that resembles the...