In short
Bone is one of the few tissues in the body that heals by regenerating rather than scarring. Understanding that process explains most of the advice you are given.
Bone is unusual. Most tissues repair with scar, which is weaker than the original. Bone regenerates, and a well-healed fracture is eventually as strong as the bone around it. That process runs through predictable stages, and most fracture advice follows from them.
The stages of healing
- 1Inflammation. Bleeding at the fracture forms a clot, and the swelling and pain of the first days are part of this necessary phase.
- 2Soft callus. Over two to three weeks a bridge of soft tissue and cartilage forms across the fracture, giving early stability but little strength.
- 3Hard callus. The soft bridge mineralises into woven bone over six to twelve weeks, which is when most fractures become clinically united.
- 4Remodelling. Over months to years the bone reorganises along lines of stress and restores its normal architecture.
Why some fractures are plated and others are not
Bone heals best when the fragments are close together and adequately stable. A cast achieves this for many fractures. Surgery is used when it cannot — when fragments are displaced, when the fracture crosses a joint surface and even a small step would damage cartilage, when the bone is inherently unstable, or when early joint movement is important.
Fixation may use plates and screws, an intramedullary nail inside the bone, or an external frame in severe injuries.
What genuinely delays healing
- Smoking. This is the single most significant modifiable factor and substantially raises the risk of delayed or failed union.
- Poorly controlled diabetes, which impairs both healing and infection resistance.
- Inadequate nutrition, especially protein, calcium and vitamin D.
- Certain medications, including long-term steroids and some anti-inflammatories.
- Movement at the fracture site from not following weight-bearing instructions.
- Poor blood supply, which is why some bones such as the scaphoid heal notoriously slowly.
Why movement matters early
Immobilising a limb protects the fracture but costs muscle strength, joint stiffness and bone density. Modern fracture care aims to stabilise the fracture well enough to allow safe early movement of the surrounding joints. This is a large part of why some fractures are fixed surgically rather than casted.
Our trauma team manages fractures from simple breaks to complex injuries, and will explain why a particular approach suits your fracture.
Frequently asked questions
How long does a fracture take to heal?+
Broadly, six to eight weeks for many upper limb fractures and twelve weeks or more for larger weight-bearing bones. Age, the specific bone, the fracture pattern and your general health all change this considerably.
Why do some fractures need surgery?+
Surgery is used when the fragments cannot be held in acceptable position by a cast, when the fracture involves a joint surface, when the bone is unstable, or when early movement is essential to a good outcome.
Does calcium help a fracture heal faster?+
Adequate calcium and vitamin D support normal healing, but taking extra beyond sufficiency does not accelerate it. Correcting a genuine deficiency does matter, particularly in older patients.
This article is general health information, not medical advice, and it cannot account for your individual circumstances. Please consult a qualified orthopaedic specialist about your own symptoms before making treatment decisions.
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