Related Experiment Video
Updated: Aug 10, 2026
05:53
The Generation of Closed Femoral Fractures in Mice: A Model to Study Bone Healing
Published on: August 16, 2018
Bone remodelling inside a cemented resurfaced femoral head
Sanjay Gupta1, Andrew M R New, Mark Taylor
1Bioengineering Science Research Group, School of Engineering Sciences, University of Southampton, Highfield, Southampton S017 1BJ, United Kingdom. sguptabec@yahoo.com
Clinical Biomechanics (Bristol, Avon)
|March 18, 2006
Summary
Bone remodelling after hip resurfacing significantly reduces initial strain risks but causes bone resorption, potentially impacting long-term fixation. Patients should limit hip loading early post-surgery to mitigate fracture risk.
Area of Science:
- Orthopedic surgery
- Biomechanical engineering
- Bone physiology
Background:
- Modern hip resurfacing arthroplasty shows promising short-term outcomes, but long-term performance and fixation failure risks remain unclear.
- Bone remodelling and altered stress distribution in the femur are hypothesized to influence fixation success.
Purpose of the Study:
- To predict long-term bone density changes and stress distribution following cemented femoral head resurfacing using computational modeling.
- To assess the impact of bone remodelling on the risk of fixation failure and femoral neck fracture.
Main Methods:
- Employed 3D finite element models and adaptive bone remodelling algorithms to simulate changes post-surgery.
- Utilized normal walking and stair climbing as loading conditions.
- Validated the remodelling simulation against clinical data for a Charnley femoral component.
Main Results:
- Immediate post-operative strain reduction of 20-70% in the bone beneath the implant.
- Initial elevated strains (0.50-0.80%) in the femoral neck region, indicating potential fracture risk.
- Significant bone resorption (60-90%) under the implant and density reduction (5-47%) in the lateral femoral head after remodelling.
- Bone apposition observed in the proximal-medial cortex; minimal changes distally.
Conclusions:
- While clinical results are encouraging, bone remodelling in the femoral head may pose long-term fixation concerns.
- Bone remodelling effectively reduces initial strain concentrations at the head-neck junction, lowering fracture risk.
- Limiting high-impact hip activities during early rehabilitation is recommended to further reduce femoral neck fracture risk.
Related Concept Videos
01:40Bone Remodeling
Bone remodeling is a continuous and balanced process of bone resorption by osteoclasts and bone formation by osteoblasts. In adults, it helps maintain bone mass and calcium homeostasis. While mechanical stress can stimulate turnover as part of the normal maintenance and reparative process, several hormones also regulate bone remodeling.
01:27Fractures: Bone Repair
Treatment for a fracture is based on the type of break, the bone affected, and the patient's age.
Minor fractures with no bone displacement are treated by immobilizing the fractured bone using a cast or splint. However, in the case of fractures with displaced bones, the broken bones are repositioned before immobilization to ensure successful healing without deformation and loss of function. The realignment of fractured bone ends is performed through a process called reduction. If the procedure...
Minor fractures with no bone displacement are treated by immobilizing the fractured bone using a cast or splint. However, in the case of fractures with displaced bones, the broken bones are repositioned before immobilization to ensure successful healing without deformation and loss of function. The realignment of fractured bone ends is performed through a process called reduction. If the procedure...
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...
01:24Bone 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...
01:27Growth of Cartilage and Bone Tissue
Chondrocytes form a temporary cartilaginous model by dividing and secreting a thick gel-like extracellular matrix. Once the chondrocytes undergo programmed cell death, osteoblasts enter the site of the cartilaginous model. The process of replacing the temporary cartilaginous model with bone in an ordered manner is called endochondral ossification. In endochondral ossification, not all of the cartilage is replaced by bone tissue. Some cartilage that performs a protective and supportive function...