Hospital-based screening for osteoporosis in both sexes aged above 50 years using prototype us bone densitometer

Abstract

In India, an orthopedician sees many patients commonly with a complaint of bone pain and other pathological bone fracture during his/her daily clinical consulting. ‘Osteoporosis’ is the cause for bone mineral loss. It affects postmenopausal women and aged population of both sexes. Many of these people are found to be asymptomatic. A simple reliable screening device is required in a hospital to identify an individual with low areal bone mineral density (aBMD, g cm−2) with good accuracy. So that, a suitable therapeutic intervention can be initiated to prevent further loss in aBMD. The dual energy X-ray absorptiometry (DXA) bone densitometer, a ‘gold’ standard device, used to measure aBMD) at the hip, spine, and forearm. In India, DXA bone densitometer is found to be costly and is restricted only in urban cities. On the other hand, quantitative ultrasound (QUS) bone densitometer is cost effective, and is widely available. Even now, the cost ofQUSis not affordable by many hospitals in rural parts of India. The aim of this study was to screen subjects of both sexes, aged 50 years and above in a hospital for osteoporosis using a low cost, portable constructed prototype of QUS bones densitometer with a good accuracy. The prototype of the device was constructed using a pair of wideband, flat, composite US transducers (diameter = 10 mm) operating at a central frequency equal to 0.5 MHz. The following US parameters were measured accurately at one-third length of ulna bone using the digital storage oscilloscope (DSO): (i) Ultrasonic transmit time (ΔT, μsec) and (ii) Ultrasonic attenuation (ΔV in volt). The device was calibrated with a step bone phantomof knownBMD (g cm−2) values. A total number of 98 women and men, aged 50 years and above were screened for the disorder in a hospital. In each subject, the QUS parameters were measured at right side ulna bone region under standard conditions using the prototype bone densitometer. In each subject, the ulna aBMD was estimated with good accuracy using the measured ΔV by the prototype bone densitometer. All the obtained data were analyzed statistically. In the total women screened, aged 50 years and above (n = 49; mean ± SD age = 57.8 ± 9.8 years) using the prototype bone densitometer, it was found that 57.1, 20.4, and 22.4%of the screened women were found to be having osteoporosis, osteopenia, and normal, respectively. On the other hand, in the total men screened, aged 50 years and above (n = 49; mean ±SDage = 60.8 ± 11.5 years), it was found that 36.7, 28.6, and 34.7%of the men were found to be having osteoporosis, osteopenia, and normal, respectively. Also, it was observed that, in osteoporotic women, the percentage difference in the mean value of estimated BMD (g cm−2) compared to normal was greater (71.8%), when compared to the same measured in osteoporotic men counterpart (59.1%). The designed prototypeUSbone densitometer can be used to screen an individual who is at risk for future osteoporosis, with good accuracy.