Why does a fractured bone hurt

Plenty of people have tales to tell of tripping up, then spending the rest of the day skiing, walking or even dancing, without realising they had a fracture. More often than not, broken bones do hurt, a lot, but if a break is small you might not notice it.

Once you dicover a bone is broken, it's important to get treatment to make sure it heals properly Credit: Alamy. But there is a peculiarity when it comes to bone fractures and pain.

It might not hurt at the time, but in , using data from the UK Biobank of half a million adults, researchers at Southampton University found that people who had fractured their arm, leg, spine or hip in the past were more likely than other people to have widespread pain in the body decades later. Luckily this kind of pain is uncommon. The hormonal changes of the menopause can lead to rapid bone loss and the frequent fractures seen in osteoporosis.

When it comes to ethnicity, in the US there are more than twice as many hip fractures in white women than black women. A number of factors have been suggested to account for the increased bone strength in black women, including higher bone mass during childhood and a lower rate of bone turnover, which might lead to a slower decline in bone mineral density with age. Having said that, black women can still suffer from osteoporosis.

In the US, for example, African American women are less likely to be referred for screening for osteoporosis than Caucasian women, and if they do receive a diagnosis they are less likely to be prescribed treatment. Although most people will experience all three types of pain, not everyone has to deal with chronic pain. On the other hand, some people may only experience acute pain.

But regardless of the type of pain you're experiencing, it's good to know more about them. Immediately after you suffer a fracture, you will experience acute pain. During this stage, medication is often prescribed to reduce the worst pain. The acute pain will decrease with time. No matter which method is used to treat your broken bone, the key is to realign the bone ends and immobilize the fracture for several weeks so the bone can set and heal properly.

In order to make this stage of the healing process as smooth as possible, it is very important that you follow the instructions of your treating physician, especially about resting and avoiding unnecessary movements so your broken bone can heal properly.

After about a week or two, the worst pain will be over. What happens next is that the fractured bone and the soft tissue around it start to heal. This takes a couple of weeks and is called subacute pain.

Subacute pain is mainly caused by the lack of movement that was necessary to help the bone heal. The inactivity may have stiffened the soft tissue around the injury and weakened the muscles. In addition to this, scarring and inflammation may have developed in the soft tissue while the fracture was healing. This may cause pain as well, and may make it difficult to move. Physical therapy is often recommended at this stage of recovery.

At this point, the body goes into action right away. A small blood clot, known as a hematoma, forms around the fracture site which then attracts molecules called white cells. Along with many other proteins, they cause the swelling, redness, and inflammation that we see and feel right after an injury. Although inflammation causes pain, it also triggers the growth of new blood vessels as well as the recruitment of other proteins.

This trigger will go on to help with the bone building process. The second phase of bone healing is where the real business of healing takes place. The reparative stage starts within about a week of the injury. A soft callus a type of soft bone replaces the blood clot that formed in the inflammatory stage. Over the next few weeks, the soft callus becomes harder.

By about 2—6 weeks, this hard callus is strong enough for the body part to be used. In the last phase, the callus matures and remodels into what we recognize as strong, healthy highly-organized bone. From start to finish, the whole process of the 3 stages of fracture healing can take anywhere from a few months to years depending on many different factors. In general, there are three stages of pain following a bone fracture.

These are referred to as acute pain, subacute pain and chronic pain. All fractures cause either all or some of these types of pain. Acute pain is that sudden, intense, kind of pain you get right after the fracture or any kind of trauma that lets you know something is wrong. During this stage, medication is often prescribed to reduce the worst pain.

The acute pain will decrease with time. Inside your body, the break has caused damage to sensitive nerves that send rapid, sharp pain signals to the brain. Over the next few hours, the cells at the fracture site release healing chemicals and signals that cause new nerves to sprout. You may need surgery so the doctor can realign your broken bone, you may need a cast or other device to keep the broken bone immobile or you may require some other medical treatment.

No matter which method is used to treat your broken bone, the key is to realign the bone ends and immobilize the fracture for several weeks so the bone can set and heal properly. Once you have moved past the initial acute pain, if it returns, it could be a signal that something is wrong. You may have bumped the bone or moved it in a way that hurt, or maybe it is not healing properly. You should let your doctor know about any unexplained return to the acute pain phase.

After about a week or two, the worst of the pain will be over. It's important not to eat or drink anything if you think you've broken a bone, as you may need a general anaesthetic to allow doctors to realign it. Older people and those with osteoporosis should be particularly careful, as their bones are weaker and may break more easily. Page last reviewed: 21 April Next review due: 21 April Home Common health questions Accidents, first aid and treatments Back to Accidents, first aid and treatments.