Dr Abhishek Saxsena
Published on October 30, 2026
Delayed Bone Healing: Why Some Fractures Take Longer
Delayed Bone Healing: Why Some Fractures Take Longer
Your plaster came off weeks ago, but the ache at the break hasn’t gone. Or your latest X-ray still shows a clear line where the bone cracked. That’s delayed bone healing, and it usually has a reason you can find and fix. Here’s what slows a fracture down, the signs to watch for, and how we treat it at Bone and Joints Clinic in Ajmer.
How long should a fracture normally take to heal?
Most minor fractures heal in six to eight weeks, while severe fractures can take three to six months. That’s the guidance given to patients by Sherwood Forest Hospitals NHS Trust in the UK. Even after the break has joined, the new bone keeps strengthening for another six to eight weeks.
Children heal faster and older adults slower, so ask your doctor what timeline to expect for your fracture.
What is delayed bone healing? Delayed union vs nonunion
Delayed bone healing means a fracture is still mending, but more slowly than expected for that bone and that injury. If healing stops completely, doctors call it a nonunion.
| Term | What it means | Typical timeline |
|---|---|---|
| Normal union | The bone heals on schedule | 6 weeks to 6 months, depending on the injury |
| Delayed union | Healing is happening, but slower than expected | No solid union on X-ray at least 3 months after the injury |
| Nonunion | Healing has stopped | US FDA definition: at least 9 months since injury, with no visible progress for 3 months in a row |
The reassuring part: true nonunion is uncommon. A 2016 JAMA Surgery study of 309,330 fractures across 18 bones found that 4.9% failed to heal.
Why do some fractures take longer to heal? 9 common reasons
Fractures heal slowly when the bone lacks a good blood supply, enough stability, or the raw materials to rebuild, or when smoking, diabetes, infection or certain medicines get in the way. Most slow fractures have two or three of these at once.
1. Which bone broke
Some bones have a poor blood supply. In the JAMA Surgery study, the scaphoid (a small wrist bone), the shinbone (tibia with fibula) and the thighbone (femur) had the highest nonunion rates.
2. How bad the injury was
Open fractures (bone through the skin), road-accident injuries and multiple fractures all damage the tissue that feeds the bone.
3. Too much movement at the break
This is the most avoidable cause we see. Taking off a cast or brace early, putting weight on the leg before you’re told to, or skipping follow-up X-rays lets the broken ends keep shifting. Bone can’t knit across a gap that keeps moving.
4. Smoking and tobacco
Nicotine narrows blood vessels and starves the healing bone of oxygen. That applies to cigarettes, bidis and chewing tobacco alike.
5. Diabetes
High blood sugar slows every stage of repair.
6. Infection
Infection is most likely after an open fracture or surgery. Bone will not heal properly until the infection is cleared.
7. Certain medicines
Painkillers, blood thinners and some seizure medicines were linked to slower healing in the JAMA Surgery data. Don’t stop any medicine yourself; tell your doctor everything you take.
8. Low vitamin D and poor nutrition
Bone is built from protein, calcium and vitamin D. If you’re short on any of them, repair slows down. A simple blood test can check your vitamin D.
9. Age, osteoporosis and weight
Weaker, thinner bone (osteoporosis) and obesity both raise the risk of slow healing.
Here’s how much some of these factors raised the odds of a fracture not healing in the 2016 JAMA Surgery study:
| Risk factor | Increase in odds of nonunion |
|---|---|
| Painkillers (NSAIDs and opioids together) | 84% higher |
| Open fracture | 66% higher |
| Blood-thinning medicines | 58% higher |
| Type 1 diabetes | 40% higher |
| Osteoporosis | 24% higher |
| Smoking | 20% higher |
| Obesity | 19% higher |
| Vitamin D deficiency | 14% higher |
What are the warning signs that a fracture isn’t healing?
The main warning sign is pain at the fracture site that hasn’t settled three months after the injury, or pain that comes back when you put weight on it. Also watch for:
- Swelling that won’t go down
- A feeling of movement, grinding or clicking at the break
- Not being able to bear weight, or the limb feeling unstable
- An X-ray that still shows a gap
If you notice redness, warmth, pus or fever around the fracture or a surgical wound, that may be infection. See a doctor the same day.
How is delayed bone healing treated?
Treatment for delayed bone healing depends on the cause: the doctor first finds out why the bone isn’t healing, then fixes that problem.
| Cause found | Typical treatment |
|---|---|
| Bone not stable enough | Better immobilisation with a cast or brace, or surgery to fix the bone with plates, rods or screws |
| Infection | Antibiotics, and sometimes surgery to clean the area |
| Gap or dead bone at the break | A bone graft to fill the gap and restart healing |
| Healing slow but stable | Protected weight-bearing, physiotherapy and close X-ray monitoring; bone stimulators in some cases |
| Health factors | Stopping tobacco, controlling blood sugar and correcting vitamin D |
Our honest view? Surgery isn’t the first answer for most slow fractures. Fixing stability, tobacco use and nutrition often gets a stalled fracture moving again.
What can you do to help your fracture heal faster?
You can speed up fracture healing by keeping the break still, stopping tobacco, eating enough protein, and keeping every follow-up appointment.
- Follow your weight-bearing instructions exactly
- Quit smoking and chewing tobacco, at least until the bone has healed
- Eat protein at every meal: dal, paneer, eggs, curd
- Keep your blood sugar in range if you have diabetes
- Go for every follow-up X-ray, even if you feel fine
Frequently asked questions about delayed bone healing
How do I know if my fracture is not healing?
A fracture may not be healing if pain, swelling or instability at the break continues three months or more after the injury, or if pain returns when you put weight on it. A follow-up X-ray, and sometimes a CT scan, confirms whether new bone is forming across the break.
Can a fracture that hasn’t healed in 6 months still heal?
Yes. Many fractures that are slow at six months still heal, especially once the cause, such as movement at the break, smoking or low vitamin D, is corrected. Doctors only call it a nonunion when healing has fully stopped, usually after about nine months with no progress for three months.
Does smoking slow down bone healing?
Yes. Nicotine narrows blood vessels and reduces the oxygen reaching the fracture. A 2016 JAMA Surgery study of over 309,000 fractures found smokers had 20% higher odds of their fracture not healing. Stopping tobacco during recovery helps the bone heal.
Do painkillers slow fracture healing?
Some can. In a 2016 JAMA Surgery study, people taking NSAIDs and opioid painkillers together had 84% higher odds of nonunion. Short-term pain relief is usually fine, but never stop or change a prescribed medicine yourself; discuss your pain relief plan with your orthopaedic doctor.
Is surgery always needed for delayed bone healing?
No. Many slow-healing fractures recover with better immobilisation, protected weight-bearing, stopping tobacco and correcting nutrition. Surgery, such as fixing the bone with plates or rods or adding a bone graft, is used when the fracture is unstable or healing has completely stopped.
Disclaimer: This article is for general information and is not medical advice. Consult a qualified orthopaedic doctor about your own condition.
