Bone density caveats.
Question:
rcjac…@pacbell.net wrote: > Hi Karen: My trainer is familiar with these balls; I think she may even > use them in some of her classes. The one I tried in the exercise > physiologist’s office seemed comfortable for a few minutes but I don’t > know how long I would want to sit on one. I am, unfortunately, down to > one cat and generally she does not claw anything except her own > furniture and toys so she is not a problem; she might be afraid of the > ball.
Ruth, I’ve got one of those balls and my cats aren’t at all afraid of it. They just think mom’s strange when she sits or lays on it, but then they often think I do strange things, like vacuuming or showering or voluntarily getting in the car to drive places. 
Judy
Response:
- Hide quoted text — Show quoted text -CatTales wrote: > rcjac…@pacbell.net wrote: > > Hi Karen: My trainer is familiar with these balls; I think she may even > > use them in some of her classes. The one I tried in the exercise > > physiologist’s office seemed comfortable for a few minutes but I don’t > > know how long I would want to sit on one. I am, unfortunately, down to > > one cat and generally she does not claw anything except her own > > furniture and toys so she is not a problem; she might be afraid of the > > ball. > Ruth, I’ve got one of those balls and my cats aren’t at all afraid of > it. They just think mom’s strange when she sits or lays on it, but then > they often think I do strange things, like vacuuming or showering or > voluntarily getting in the car to drive places. > Judy
Judy,This is totally off-topic but you’ve tickled my funny bone and I can’t resist. My dog loathes water of any kind – and I’m quite certain he thinks both my husband and I are nuts when we *voluntarily* -without being picked up and taken to the bathroom – actually get into the shower. As for getting into the pool!! Boy we must be totally mad. Terri
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Sorry for not responding to it, Ruth. I don’t know. I am fascinated by the evidence that bone density can flutuate by as much as 6% over the space of a few minutes and have put this information into the same mental file as the 10% of patients on placebo in a fosomax study who increased their bone density measurably over the course of the study. It begins to appear that what we don’t know about bone density and its measurement may be far greater than what we do. To my knowledge osteoporosis/lowered bone density is not painful so I would assume that there would be no change or at least not a correlation. Lower back pain is far more likely to be the result of posture problems, prior injury, or degenerative disc (as opposed to bone) disease. My family history is a disaster for this problem – Father and paternal aunt – aunt has had a fusion; 7 out of 11 siblings two of whom have had surgery with no relief. My daughter began having back pain at 15 – a nephew at 13, and another nephew at 11- all three show X-ray evidence of the spurring of degenerating spinal discs. Terri – Hide quoted text — Show quoted text -rcjac…@pacbell.net wrote: > Karen Kay wrote: > (my previous post(s) snipped) > > Some of them are round, some of them have ‘feet’ on the bottom so you > > can use them as chairs. > > They are about two feet in diameter. I can see that with the cats, > > you’d want to put them away. Has your trainer used these before? They > > are incredibly versatile. > > Is sitting lotus style good for your back?! (Most floor sitting (which > > is essentially what crossing your legs is) is not good for your lower > > back. I haven’t been able to sit lotus style for many years because of > > one of my knees, so I haven’t tried this.) > > Karen > > ka…@wordwrite.com > Hi Karen: My trainer is familiar with these balls; I think she may even > use them in some of her classes. The one I tried in the exercise > physiologist’s office seemed comfortable for a few minutes but I don’t > know how long I would want to sit on one. I am, unfortunately, down to > one cat and generally she does not claw anything except her own > furniture and toys so she is not a problem; she might be afraid of the > ball. > I have been sitting lotus position since I was 8 years old and my > parents and I visited a garden somewhere near Santa Barbara where there > was a Buddha statue. I do not know if it is good or bad for my back, > but I *can* trace the current back pain to my running/aerobics days 15 > years ago and to my fall in Seattle 9 years ago, and to this furniture > purchased approx. 2 years ago. Fortunately, unlike my insomnia, the > back pain is not severe enough to be anything other than an annoyance. > It certainly is exacerbated by doing "back stupid" things such as > bending over, rather than squatting, to lift cat dishes, and does not > improve by sitting on a hard surface such as the floor. > Terri, I was actually looking to you for this: I still haven’t an answer > to my original question on this thread which was: if my back hurts, will > a DEXA show bone loss relative to a DEXA taken when my back doesn’t > hurt? Thanks/RuthJ
Response:
Karen Kay wrote:
(my previous post(s) snipped) – Hide quoted text — Show quoted text -> Some of them are round, some of them have ‘feet’ on the bottom so you > can use them as chairs. > They are about two feet in diameter. I can see that with the cats, > you’d want to put them away. Has your trainer used these before? They > are incredibly versatile. > Is sitting lotus style good for your back?! (Most floor sitting (which > is essentially what crossing your legs is) is not good for your lower > back. I haven’t been able to sit lotus style for many years because of > one of my knees, so I haven’t tried this.) > Karen > ka…@wordwrite.com
Hi Karen: My trainer is familiar with these balls; I think she may even use them in some of her classes. The one I tried in the exercise physiologist’s office seemed comfortable for a few minutes but I don’t know how long I would want to sit on one. I am, unfortunately, down to one cat and generally she does not claw anything except her own furniture and toys so she is not a problem; she might be afraid of the ball. I have been sitting lotus position since I was 8 years old and my parents and I visited a garden somewhere near Santa Barbara where there was a Buddha statue. I do not know if it is good or bad for my back, but I *can* trace the current back pain to my running/aerobics days 15 years ago and to my fall in Seattle 9 years ago, and to this furniture purchased approx. 2 years ago. Fortunately, unlike my insomnia, the back pain is not severe enough to be anything other than an annoyance. It certainly is exacerbated by doing "back stupid" things such as bending over, rather than squatting, to lift cat dishes, and does not improve by sitting on a hard surface such as the floor. Terri, I was actually looking to you for this: I still haven’t an answer to my original question on this thread which was: if my back hurts, will a DEXA show bone loss relative to a DEXA taken when my back doesn’t hurt? Thanks/RuthJ
Response:
Karen Kay wrote: > Pat Kight <kig…@ucs.orst.edu> wrote: >… But I figure if I’m disciplined enough to meet writing > > deadlines and learn my lines when I’m in a play, I ought to be > > disciplined enough to keep up at least a minimal exercise regimen. > Yeah, but you see the results of those things faster than you do the > results of exercise.
Heh. Well, I certainly see the results fast if I *don’t* get them done! –Pat Kight kig…@peak.org
Response:
Karen Kay wrote, re exercise: >If I don’t make it >semi-automatic, part of a routine I don’t have to think about, I just >won’t do it. If I have to think about it at all, sad to say, I’ll find >something I’d rather do!
Me too. That’s why I moved to the inner city, where the buses are inconvenient, and replaced my car with a bicycle. It forces a minimal amount of exercise upon my slothful self. >So sue me, I’m human.
Sorry, I don’t do lawsuits. I’ll leave that to the professionals on the newsgroup (you know who you are). But I doubt that the professionals consider humanity to be an actionable offense. Regards vlhb…@aol.com
Response:
Robert Ames wrote: > In article <35B52418…@pacbell.net>, rcjac…@pacbell.net wrote: > >Thank you Terri. A question: from someone with back problems: my > Have you tried using a rocking chair at home? (And not one of those > upholstered ones).
No, I don’t think I would find a rocking chair comfortable. My trainer is looking into one of those, what I will call posture balls, Karen is talking about (the one I tried at the exercise physiologist’s office was round). I would like to try one before I buy one, and hope it will fit in the closet when not in use. Also try to visualize that often there is an 11 pound cat on my lap, and I have my legs crossed lotus-style, and the effect is probably to throw my back out of alignment. At 17, I can’t train the cat but I’m trying to train myself to sit straighter. RuthJ
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When my lower back is especially bothersome – injury to L3-5 30 years ago and now moderate degenerative disc disease to go with it – I lie on the floor with my calves and feet on a certain chair that’s just high enough to provide some traction. 20 minutes three times a day will often make a tremendous difference in three days or so. I’ve had the chair for more than 20 years and can’t imagine giving it up no matter how ratty it gets. Terri – Hide quoted text — Show quoted text -Karen Kay wrote: > rcjac…@pacbell.net wrote: > > No, I don’t think I would find a rocking chair comfortable. My trainer > > is looking into one of those, what I will call posture balls, Karen is > > talking about (the one I tried at the exercise physiologist’s office was > > round). > Some of them are round, some of them have ‘feet’ on the bottom so you > can use them as chairs. > > I would like to try one before I buy one, and hope it will fit > > in the closet when not in use. > They are about two feet in diameter. I can see that with the cats, > you’d want to put them away. Has your trainer used these before? They > are incredibly versatile. > > Also try to visualize that often there > > is an 11 pound cat on my lap, and I have my legs crossed lotus-style, > > and the effect is probably to throw my back out of alignment. > Is sitting lotus style good for your back?! (Most floor sitting (which > is essentially what crossing your legs is) is not good for your lower > back. I haven’t been able to sit lotus style for many years because of > one of my knees, so I haven’t tried this.) > Karen > ka…@wordwrite.com
Response:
In article <35B52418…@pacbell.net>, rcjac…@pacbell.net wrote: >Thank you Terri. A question: from someone with back problems: my
Have you tried using a rocking chair at home? (And not one of those upholstered ones).
Response:
Karen Kay wrote: > The problem w/ chiropractors prescribing exercises is that they don’t > generally (in my limited experience) have enough of a repertoire to > give you a comprehensive program. (This is where physical therapy was > useful for me.)
That’s probably true in general, but my chiropractor started out as a physical therapist and then went back sto school, so she’s got a pretty good bag of tricks. At times, though, her "prescription" is along the lines of "Ok, you need to find a reliable exercise regimen that you’ll actually follow. Here are some books to read …" > > Now if I could only develop the self-discipline > > to *do* that in a more systematic way… > This remains a problem for me. Face it, if I didn’t have this problem > to start with, I probably wouldn’t have gotten into such trouble in > the first place.
I console myself (or perhaps justify my life of sloth) by noting that some of my extremely athletic friends are also suffering from chronic pain in their middle age, for a whole *different* set of reasons. Half the runners I know have destroyed their knees and/or ankles. As a friend likes to say, "We just weren’t designed to walk upright." > My solution so far has been to try to build it into my life. I have a > foam roller next to my bed
I’m not visualizing this well — can you describe it? > If I don’t make it > semi-automatic, part of a routine I don’t have to think about, I just > won’t do it. If I have to think about it at all, sad to say, I’ll find > something I’d rather do! So sue me, I’m human.
My problem exactly. Given a choice between physical activity and anything else that’s even *vaguely* pleasurable, I tend to go for the pleasure. But I figure if I’m disciplined enough to meet writing deadlines and learn my lines when I’m in a play, I ought to be disciplined enough to keep up at least a minimal exercise regimen. –Pat Kight kig…@peak.org
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Karen Marshall wrote: > A quick question Ruth. Have you ever had an MRI on your back? An x-ray > can not show everything only bone. Have you been to an orthopedic? Just > so you know, I am dead set against chiropractors. > Karen Marshall
(my previous post and Terri’s snipped) Hi Karen: I had an MRI on my left shoulder and I would *never* go through that again! Horrifying, and painful (for me). I also am dead set against chiropractors. I did have x-rays of my lower back last year when I went to the second orthopedic idiot for a second opinion on my shoulder and he saw no abnormality. What I *think* is going on with my back is: in 1983 after a totally sedentary life I started jogging and doing aerobics and promptly developed stress fractures of both ankles and my sacroiliac. I continued these activities nevertheless, and in 1989 when I was temporarily up in Seattle I "fell on my ass on the ice" in exactly the same spot. At that time, an x-ray of my lower back showed a healed stress fracture of my right sacroiliac. After that I could not bend over for 6 months, and eventually my back got better, but I’ve had problems on the right side only ever since. My Mother said she had a "high hip" on her right side, and my body certainly is not symmetrical, so I suspect my hips my be slightly uneven. There is also, apparently, a connection between some muscle swelling in this area and my periods (according to my acupuncturist and my trainer). I think the main problem I have now is this !@#$%^&*()_++! furniture I bought when I moved into a larger apartment than I needed, and when I get the lumbar support pillow Karen Kay has been telling me to get for some time, it should help. If the problem persists, along with the insomnia, next time I’m due for a checkup, I’ll discuss it with my doctor. Thanks for asking. RuthJ
Response:
>Hypoint wrote: >> So the risk of non-vertebral fractures almost doubles every ten years for women >> 55 and older given identical T-scores. By which I would assume the risk of >> fracture is related to risk of falling rather than T-score.
More on this from http://weber.u.washington.edu/~bonephys/opop.html Impact factors FALLS The risk factors for falls include use of sedatives, previous fall, cognitive impairment, visual impairment, lower-extremity disability, foot problems, and gait abnormalities. DIRECTION OF FALL A recent study showed that women who fell on their side had a relative risk of hip fracture of 5.7 compared to those who fell in other directions. This is a much greater risk than a lower bone density, in which a standard deviation decrease increased the risk by a factor of 2. Gait speed plays a role. Women who walk faster are more likely to have forward momentum, and if they fall they land on their wrist. This may lead to a distal radius fracture, but that is much less devastating than a hip fracture.
Response:
Karen Kay wrote:
(re: regimens that can help get one’s body back in balance) . So can chiropracty, but unless you condition the muscles through > specific exercises, the chiropractic adjustment won’t stay and you’ll > have to go back frequently. (That’s why I can’t imagine thinking that > a chiropractor could ‘cure’ you.)
This would explain why my chiropractor "prescribes" exercises, and discourages me from coming to see her unless I’m experiencing sudden or unusual pain, such as from a muscle injury. Her position is that she can help relieve the immediate pain, but that she can’t "cure" it for me — that requires work on my part to balance and strengthen my skeleto-muscular system. Now if I could only develop the self-discipline to *do* that in a more systematic way… –Pat Kight kig…@peak.org
Response:
Good question. I will try and explain the best I can. Don’t hesitate to ask if I am not clear. My father is a doctor and back in the dark ages when I was growing up, he always told me that people became chiropractors when they couldn’t make it through medical school. I guess he said this because the ones he knew hadn’t made it. Prejudice? Maybe Secondly, I had a mother-in-law, brother-in-law and sister-in-law who all went to chiropractors for years. ( not the same ones by the way) They all had back or in the case of my brother-in-law, hip problems and pain. As I said they went for years and did not get better (permanently). Just kept spending the money. They all finally got relief when they went to orthopedics and had disk surgery or hip replacement (brother-in-law) I just think of all the years of suffering they went thru that could have been avoided if they consulted an orthopedic first. This is all my opinion and if someone believes in them, I don’t try and change their mind. I just bite my tongue and keep quiet. I *would not* recommend to someone, though, to go see one if they complained about back pain and wanted a suggestion on who to see. I hope that answers your question, Karen Karen Marshall On 22 Jul 1998 16:42:20 GMT, Karen Kay <ka…@wordwrite.com> wrote: – Hide quoted text — Show quoted text ->Karen Marshall <kar…@yosemite.net> wrote: >> Just so you know, I am dead set against chiropractors. >Why? >Karen > ka…@wordwrite.com
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On Tue, 21 Jul 1998 06:41:23 -0400, Terri <vl-hb…@erols.com> wrote: >As for the >differences in machines – I’m not sure I would even view machines made by >the same manufacturer as comparable. These machines are calibrated by >humans after all.
Exactly – which is why I am insisting on having my followup scan done on the same machine (35 miles away) rather than the newly installed one 10 miles away. Even so, I hear the machine has been moved across the road and so may well have changed *its calibration. Any change of less than 5% I shall consider to be ignorable. An interesting remark made on one of the sites linked from the asm site is that "2 measurements over 3 years is preferable to 3 measurements over 2 years" and intuitively this would decrease the effect of measuerment error – "annually" anyway! Well now I’ve got started I may as well post a couple of related items which I put on the website a long time ago: http://www.rad.washington.edu/Books/Approach/Osteopenia.html Remember Resnick’s Rule: "You can take a normal patient and an abnormal X-ray technician and produce osteoporosis at will." http://www.priocal.se/nomenclature.html This is the site of a Swedish manufacturer of DEXA machines. They imply that not only abnormal technicians but abnormal machines may be the reason for "osteoporosis"when they say: "Accuracy defines how correct our measurement is compared to the true value. This is important for diagnosis Precision defines the variability occurring with repeated measurements over time. This is important for following changes over time of bone density of a patient. To be able to identify a change in bone density with a bone densitometer with a precision error of 1%, the actual change needs to be at least 2.8 % for it to be significant. Using equipment with an error of 5%, the actual change needs to be at least 14%. Normal bone loss just after menopause is appoximately 3% per year. "
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Terri wrote: > Thank you for posting this, Pat. Bone density measurement, especially that > reported from DEXA scans is always reported as something absolutely static > – and any decrease is viewed with alarm. Interesting that it can vary by > as much as 6% over a matter of minutes.
(the rest of Terri’s, and Pat’s posts snipped) Thank you Terri. A question: from someone with back problems: my wearing the brace is *not* helping, it’s making me worse. If I had a DEXA when my back hurt, would it show bone loss? Would it show an increase in bone mass after an acupuncture treatment when my back muscles are relaxed? In other words, are these DEXA scans, like the hormone blood tests, basically "snapshots" of our bones on a particular day? RuthJ
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On Mon, 20 Jul 1998 20:41:27 GMT, ti…@cheerful.com wrote: > Bone density "changes" *are* used to justify the use of >so-called anti osteoporotic drugs and often uncritically.
Further to this, I have just discovered another site at http://www.brighamrad.harvard.edu/research/labs/IPL/sandor/sandor.html which is extremely dense and requires more concentration than I can spare at the moment though I certainly will later. The summary below though is of consequence and relatively easy to understand. Note however the everpresent "Further studies are neeeded" caveat. Note too that they refer to "atraumatic" fractures, the earlier site I quoted referred to "fragility" fractures – yet the press and drug companies refer to "fractures" without the allimportant qualification. Pat(Crone) ——- To summarize, linear discriminant analysis of spinal CT scans is a promising method that can identify three patients groups below the fracture line of the BMD vs. Age plot: (1) osteoporotic patients, who have already suffered atraumatic fractures somewhere in their skeleton, (2) normal patients, who have no fractures and whose BMD distribution allocates them to the normal diagnostic category, and (3) potential patients, who have no fractures but whose BMD distribution is characterized by the discriminant analysis as osteoporotic. This split in the nonfracture cases shows the heterogeneity of the patients who have low bone density, and it has possible implications for patient treatment. The separation of the groups cannot be achieved with the model that is proposed by the World Health Organization, which lumps together all patients whose BMD values are low and within arbitrarily defined ranges. Further studies confirming these results are needed.
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A quick question Ruth. Have you ever had an MRI on your back? An x-ray can not show everything only bone. Have you been to an orthopedic? Just so you know, I am dead set against chiropractors. Karen Marshall – Hide quoted text — Show quoted text -On Tue, 21 Jul 1998 16:28:24 -0700, rcjac…@pacbell.net wrote: >Terri wrote: >> Thank you for posting this, Pat. Bone density measurement, especially that >> reported from DEXA scans is always reported as something absolutely static >> – and any decrease is viewed with alarm. Interesting that it can vary by >> as much as 6% over a matter of minutes. >(the rest of Terri’s, and Pat’s posts snipped) >Thank you Terri. A question: from someone with back problems: my >wearing the brace is *not* helping, it’s making me worse. If I had a >DEXA when my back hurt, would it show bone loss? Would it show an >increase in bone mass after an acupuncture treatment when my back >muscles are relaxed? In other words, are these DEXA scans, like the >hormone blood tests, basically "snapshots" of our bones on a particular >day? RuthJ
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Since Evista is being discussed , I think the following information may be of interest even though it does not directly relate to the drug. Bone density "changes" *are* used to justify the use of so-called anti osteoporotic drugs and often uncritically. This is from an excellent unfunded site at http://weber.u.washington.edu/~bonephys/opbmd.html ——— Bone density to follow a patient’s clinical course, ie, reproducibility Studies frequently report reproducibility of DEXA between 1 and 2%. This is the average precision; the range is rarely reported. But repeat measurements may show as much as 6% difference. These charts shows the percent difference in total hip bone density when 300 normal elderly men and women walked around the room between measurements. For example, about 20% have lost at least 2%, and 5.5% of women lost more than 4%. ——— Standardization The three manufacturers of DEXA equipment do not give STANDARDIZED RESULTS. The differences are clinically important, making it difficult to compare a measurement made from one machine to the other. For example, the hip bone density on a Lunar scan is about 5% higher than on a Hologic scan. If the physician must try to compare studies done on different machines, the best way is to apply the following equations which will give a standardized value. Total Hip Hologic: 1.008 times BMD + 0.006 Lunar: 0.979 times BMD – 0.031 Norland: 1.012 times BMD + 0.026. Reference: Bone 1997, vol 21 p. 369. Spine Hologic: 1.0550 (BMD – 0.972) +1.0436 Lunar: 0.9683 (BMD – 1.100) + 1.0436 Norland: 0.9743 (BMD – 0.969) + 1.0436 Using these equations, the average error for a patient was 3.5% when measured on different machines. Reference: Hui, SL, et al. Universal Standardization of Bone Density Measurements: A Method with Optimal Properties for Calibration Among Several Instruments. J Bone Mineral Research 1997;12:1463-70. ————- Use of bone density to predict fracture risk It is not possible to correctly interpret a bone density test in the absense of other clinical information. Age, previous fractures, direction of falls, race, and risk factors are also important determinants of fracture. At the same bone density, each decade of age will double the risk of a fracture. <snip> The short-term risk of a fracture cannot be determined from the WHO categories. For example, a prospective study using radius measurements and recording clinical, non-vertebral fractures showed that a 55 year old woman with a T-score of -1.0 (osteopenia) has a fracture risk of about 1.6%/yr over the next 5 years, whereas a 75 year old woman with the identical T-score has a risk of 6%/year.
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> For example, a prospective study using radius >measurements and recording clinical, non-vertebral fractures showed >that a 55 year old woman with a T-score of -1.0 (osteopenia) >has a fracture risk of about 1.6%/yr over the next 5 years, whereas a >75 year old woman with the identical T-score has a risk of >6%/year.
So the risk of non-vertebral fractures almost doubles every ten years for women 55 and older given identical T-scores. By which I would assume the risk of fracture is related to risk of falling rather than T-score. Wendy hypo…@aol.com
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Hypoint wrote: > > For example, a prospective study using radius > >measurements and recording clinical, non-vertebral fractures showed > >that a 55 year old woman with a T-score of -1.0 (osteopenia) > >has a fracture risk of about 1.6%/yr over the next 5 years, whereas a > >75 year old woman with the identical T-score has a risk of > >6%/year. > So the risk of non-vertebral fractures almost doubles every ten years for women > 55 and older given identical T-scores. By which I would assume the risk of > fracture is related to risk of falling rather than T-score. > Wendy > hypo…@aol.com
Bingo!! Terri
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Thank you for posting this, Pat. Bone density measurement, especially that reported from DEXA scans is always reported as something absolutely static – and any decrease is viewed with alarm. Interesting that it can vary by as much as 6% over a matter of minutes. So what exactly are drugs that show a 2% increase actually showing – measurement error? As for the differences in machines – I’m not sure I would even view machines made by the same manufacturer as comparable. These machines are calibrated by humans after all. Terri – Hide quoted text — Show quoted text -ti…@cheerful.com wrote: > Since Evista is being discussed , I think the following information > may be of interest even though it does not directly relate to the > drug. Bone density "changes" *are* used to justify the use of > so-called anti osteoporotic drugs and often uncritically. This is from > an excellent unfunded site at > http://weber.u.washington.edu/~bonephys/opbmd.html > ——— > Bone density to follow a patient’s clinical course, ie, > reproducibility > Studies frequently report reproducibility of DEXA between 1 and 2%. > This is the average precision; the range is rarely reported. But > repeat measurements may show as much as 6% difference. These charts > shows the percent difference in total hip bone density > when 300 normal elderly men and women walked around the room between > measurements. For example, about 20% have lost at > least 2%, and 5.5% of women lost more than 4%. > ——— > Standardization > The three manufacturers of DEXA equipment do not give STANDARDIZED > RESULTS. The differences are clinically important, > making it difficult to compare a measurement made from one machine to > the other. For example, the hip bone density on a Lunar > scan is about 5% higher than on a Hologic scan. If the physician must > try to compare studies done on different machines, the best > way is to apply the following equations which will give a standardized > value. > Total Hip > Hologic: 1.008 times BMD + 0.006 > Lunar: 0.979 times BMD – 0.031 > Norland: 1.012 times BMD + 0.026. > Reference: Bone 1997, vol 21 p. 369. > Spine > Hologic: 1.0550 (BMD – 0.972) +1.0436 > Lunar: 0.9683 (BMD – 1.100) + 1.0436 > Norland: 0.9743 (BMD – 0.969) + 1.0436 > Using these equations, the average error for a patient was 3.5% when > measured on different machines. Reference: Hui, SL, et al. > Universal Standardization of Bone Density Measurements: A Method with > Optimal Properties for Calibration Among Several > Instruments. J Bone Mineral Research 1997;12:1463-70. > ————- > Use of bone density to predict fracture risk > It is not possible to correctly interpret a bone density test in the > absense of other clinical information. Age, previous fractures, > direction of falls, race, and risk factors are also important > determinants of fracture. At the same bone density, each decade of age > will double the risk of a fracture. > <snip> > The short-term risk of a fracture cannot be determined from the WHO > categories. For example, a prospective study using radius > measurements and recording clinical, non-vertebral fractures showed > that a 55 year old woman with a T-score of -1.0 (osteopenia) > has a fracture risk of about 1.6%/yr over the next 5 years, whereas a > 75 year old woman with the identical T-score has a risk of > 6%/year.
