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A review of mouse critical size defect models in weight bearing bones
Jonathan S Harris1, Thomas B Bemenderfer, Alexander R Wessel
1Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis 46202, USA.
Abstract:
Current and future advances in orthopedic treatment are aimed at altering biological interactions to enhance bone healing. Currently, several clinical scenarios exist for which there is no definitive treatment, specifically segmental bone loss from high-energy trauma or surgical resection - and it is here that many are aiming to find effective solutions. To test experimental interventions and better understand bone healing, researchers employ critical size defect (CSD) models in animal studies. Here, an overview of CSDs is given that includes the specifications of varying models, a discussion of current scaffold and bone graft designs, and current outcome measures used to determine the extent of bone healing. Many promising graft designs have been discovered along with promising adjunctive treatments, yet a graft that offers biomechanical support while allowing for neovascularization with eventual complete resorption and remodeling remains to be developed. An overview of this important topic is needed to highlight current advances and provide a clear understanding of the ultimate goal in CSD research--develop a graft for clinical use that effectively treats the orthopedic conundrum of segmental bone loss.
Insights
Researchers are developing new bone grafts to heal critical size bone defects (CSDs) caused by trauma or surgery. The goal is a graft that supports healing, promotes new blood vessel growth, and is fully replaced by natural bone.
Area of Science:
- Orthopedic surgery
- Biomaterials science
- Regenerative medicine
Background:
- Segmental bone loss presents a significant clinical challenge with no definitive treatment.
- Critical size defect (CSD) models in animal studies are crucial for evaluating bone healing interventions.
Purpose of the Study:
- To provide an overview of current critical size defect (CSD) models in orthopedic research.
- To discuss existing scaffold and bone graft designs for enhancing bone healing.
- To highlight the unmet need for a bone graft that provides biomechanical support, promotes neovascularization, and allows complete remodeling.
Main Methods:
- Review of existing literature on critical size defect (CSD) models.
- Analysis of current scaffold and bone graft designs.
- Evaluation of outcome measures used in bone healing studies.
Main Results:
- Various CSD models exist with specific characteristics for studying bone healing.
- Numerous promising bone graft designs and adjunctive treatments have been developed.
- A significant gap remains in developing a graft that combines biomechanical support with biological integration and remodeling.
Conclusions:
- Effective treatment for segmental bone loss remains an orthopedic challenge.
- Continued research into advanced graft designs is essential for clinical translation.
- The ultimate goal is to develop a clinically viable graft for segmental bone loss.
