Skip to 0 minutes and 2 secondsOsteoporosis and bone loss are quite closely linked. I guess it depends what you mean by osteoporosis, and to most patients, osteoporosis means fractures, broken bones, and of course bone loss is an important component of that. So it's how much bone we get when we're at our peak in our 20s and 30s, and then how much bone we lose after that, that determines our bone strength in the future. And our bone strength determines how much risk we are at of breaking bones in the future. But of course, there's more to fracture risk than just bone loss or bone strength. For example, if I have weak bones I still have to have some degree of trauma to break the bones.
Skip to 0 minutes and 43 secondsSo if I'm at increased risk of falling, for example, then that increases my risk of fracture independently of the strength of my bones. So if we're going to talk about fracture risk to patients, then we need to take into account more than just osteoporosis or the measure of bone strength. A patient is identified by their GP or other healthcare professional that they might be at risk of osteoporosis. For example, they're taking glucocorticoids for their inflammatory bowel disease, they get a referral on to the unit here. They come along and have a scan on a densitometer. The densitometer basically has energies of x-rays that set off from below the patient.
Skip to 1 minute and 23 secondsWe know the energy that sets off and we know the energy that is detected by detectors over the top of the patient. If we know how much energy set off and how much arrives, we know how much was absorbed in the middle. And that allows us to convert that missing bit, if you like, into measures of bone mass, as well as fat mass and lean mass. When we have a patient sitting in front of us in the clinic, they're interested in what's going to happen to them in the future, what's their risk of fracture in the future.
Skip to 1 minute and 50 secondsAnd of course knowing whether they've got osteoporosis or not is important, but it's only really part of the equation, if you like, that we can use to calculate their future fracture risk. We know that there are risk factors that are independent of osteoporosis. And those risk factors have been brought together in several tools around the world to try and improve our prediction of fracture risk. The FRAX tool is a tool that was developed here at the University of Sheffield, and it's probably the most widely validated and most widely used tool that we have available to us. So the FRAX tool is just over my shoulder on the screen here.
Skip to 2 minutes and 28 secondsAnd as you can see, it's a fairly simple questionnaire based system that's designed to be used in primary care by GPs, by practice nurses and others. Basically it just asks a number of questions about the age of the individual, the gender of the individual. And then, have you broken a bone before? Has either of your parents broken their hip in the past? Have you ever had to use glucocorticoid treatments, prednisolone for example, for chest diseases and other diseases? Are you a smoker? Do you have rheumatoid arthritis? Do you drink more than three units of alcohol per day? And do you have any other conditions that can be associated with osteoporosis?
Skip to 3 minutes and 10 secondsAnd it puts those together in an equation, and works out the chances of breaking a bone in the next ten years. It works out the chances of you breaking your hip in the next ten years. And it works out the chances of you breaking either your hip, your wrist, a spine fracture, or a shoulder fracture. And those two numbers are generated and help the clinicians to make a decision as to whether this patient is a sufficiently high risk that they may need further investigations or they may need treatment.
Osteoporosis and the risk of fracture
In this video, Professor Eugene McCloskey from the University of Sheffield discusses how bones change with age and a common age-related bone condition, osteoporosis.
Bone strength decreases with age and significantly lower bone density places individuals at higher risk of breaking (fracture) under stress that healthy bone could withstand. Osteoporosis is a condition in which low bone strength leaves the bone framework brittle and susceptible to fracture.
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