This 2021 Nature Reviews Disease Primers article synthesizes current knowledge on fracture non-union across epidemiology, pathophysiology, classification, diagnosis, and surgical management. It answers the question: why do some fractures fail to heal, and how should that inform treatment? The review spans basic science through operative strategy, making it a comprehensive reference for any trainee encountering this complication.
A fracture that fails to heal is not just a radiographic finding — it carries a worse quality-of-life impact than stroke or type 1 diabetes. Yet non-union is often preventable.
When you fix a fracture, you are setting the mechanical environment that determines whether bone or fibrous tissue forms. Keep axial interfragmentary movement between 0.2–1 mm and gap between 1–3 mm for diaphyseal healing. Shear movements are more harmful than axial micromotion. This is why transverse diaphyseal fractures have higher reoperation rates than oblique or spiral patterns.
At every fracture follow-up, apply Weber and Cech: callus on X-ray means a mechanical problem (add stability); no callus means a biological problem (add biology). If you see clinically appreciable motion at 6 weeks, or absent callus on multiple cortices at 6 weeks, intervene early. The window to prevent established non-union is narrow.
Before any elective non-union repair, screen and optimize modifiable factors: stop NSAIDs, verify smoking cessation with nicotine levels, check vitamin D (deficient in 68% of non-union patients), and screen for diabetes. Most non-unions can be salvaged with stabilization alone. Bone graft is reserved for oligotrophic, atrophic, and defect non-unions, not hypertrophic ones.
This 2021 Nature Reviews Disease Primers article synthesizes current knowledge on fracture non-union across epidemiology, pathophysiology, classification, diagnosis, and surgical management. It answers the question: why do some fractures fail to heal, and how should that inform treatment? The review spans basic science through operative strategy, making it a comprehensive reference for any trainee encountering this complication.
A fracture that fails to heal is not just a radiographic finding — it carries a worse quality-of-life impact than stroke or type 1 diabetes. Yet non-union is often preventable.
When you fix a fracture, you are setting the mechanical environment that determines whether bone or fibrous tissue forms. Keep axial interfragmentary movement between 0.2–1 mm and gap between 1–3 mm for diaphyseal healing. Shear movements are more harmful than axial micromotion. This is why transverse diaphyseal fractures have higher reoperation rates than oblique or spiral patterns.
At every fracture follow-up, apply Weber and Cech: callus on X-ray means a mechanical problem (add stability); no callus means a biological problem (add biology). If you see clinically appreciable motion at 6 weeks, or absent callus on multiple cortices at 6 weeks, intervene early. The window to prevent established non-union is narrow.
Before any elective non-union repair, screen and optimize modifiable factors: stop NSAIDs, verify smoking cessation with nicotine levels, check vitamin D (deficient in 68% of non-union patients), and screen for diabetes. Most non-unions can be salvaged with stabilization alone. Bone graft is reserved for oligotrophic, atrophic, and defect non-unions, not hypertrophic ones.