Pitfalls in bone mineral density measurements

Imaging in osteoporosis in rheumatic diseases

Osteoporosis is a common comorbidity of all major rheumatic diseases, and manifests itself both systemically and locally. Systemic bone loss manifests because of several factors, primarily inflammation, immobility, and commonly used medical treatment for rheumatic diseases. Local bone loss manifests as periarticular demineralization and bone erosion due to local release of inflammatory agents and cytokines, which promote bone resorption. All these factors contribute to the phenomenon of arthritis-associated osteoporosis. This review summarized the currently available and used methods that play a role in the diagnosis and monitoring of osteoporosis and in the detection of osteoporotic fractures.

Appropriate osteoporosis treatment by family physicians in response to FRAX vs CAROC reporting: results from a randomized controlled trial

Canadian guidelines recommend either the FRAX or the Canadian Association of Radiologists and Osteoporosis Canada (CAROC) fracture risk assessment tools to report 10-yr fracture risk as low (<10%), moderate (10%-20%) or high (>20%). It is unknown whether one reporting system is more effective in helping family physicians (FPs) identify individuals who require treatment. Individuals ≥50 yr old with a distal radius fracture and no previous osteoporosis diagnosis or treatment were recruited. Participants underwent a dual-energy x-ray absorptiometry scan and answered questions about fracture risk factors. Participants' FPs were randomized to receive either a FRAX report or the standard CAROC-derived bone mineral density report currently used by the institution. Only the FRAX report included statements regarding treatment recommendations. Within 3 mo, all participants were asked about follow-up care by their FP, and treatment recommendations were compared with an osteoporosis specialist. Sixty participants were enrolled (31 to FRAX and 29 to CAROC). Kappa statistics of agreement in treatment recommendation were 0.64 for FRAX and 0.32 for bone mineral density. The FRAX report was preferred by FPs and resulted in better postfracture follow-up and treatment that agreed more closely with a specialist. Either the clear statement of fracture risk or the specific statement of treatment recommendations on the FRAX report may have supported FPs to make better treatment decisions.

[Pitfalls and difficulties in interpretation of bone densitometry]

The clinical relevance of osteoporosis as a frequent systemic skeletal disease is to be found in fractures and their consequences. For prevention of these disease manifestations great importance must be attached to a safest possible diagnosis even before the occurrence of the first fracture and osteodensitometry is a well established technique for this purpose. Among the different measurement procedures DXA (dual-energy X-ray absorptiometry) has become the gold standard worldwide. This method is seen as very reliable and adequately precise. Prerequisites for these characteristics are the correct interpretation of the measurement data obtained by taking into consideration all potential influencing factors which can either false positively or false negatively influence a single value as well as the calculated mean value and the T and Z scores. Thus, exact knowledge of potential sources of error is of crucial importance. The present study shows important sources of error and difficulties in interpretation as well as a discussion of the options for their prevention. For the clinical practice osteodensitometry is to be seen as an important diagnostic component, which can only been interpreted meaningfully with respect to the clinical data.

Guidelines for the diagnosis of osteoporosis: T-scores vs fractures

The development of bone mineral densitimometry methodologies, especially central dual energy X-ray absorptiometry (DXA) methods have allowed this quantitative tool to be used to diagnose osteoporosis before the first fragility fracture has occurred. The World Health Organization osteoporosis working group set the stage for the BMD cut-off criteria development. The wide application of DXA has brought the treatment of osteoporosis to the primary care level, a very necessary step if this increasingly prevalent disease is to have a decline in its incidence. The most difficult osteoporosis cases, for which there are many and their associated difficult DXA results and interpretation will always require specialists' involvement. In particular, the embracement of the WHO absolute fracture risk validated project will take DXA to a much greater level of value in making management decisions. In particular, the WHO absolute risk data will allow physicians, health-economic policy makers, and payors of medical services to come closer together to decide which patients are at a level of unacceptable fracture risk that justifies treatment intervention. The implementation of this validated project will also remove the unacceptable subjective computer printouts on DXA reports that often lead to the over-treatment of low risk patients and at times the under-treatment of high risk patients. The evolution of the clinical interpretation of bone densitometry has been a work in progress. Challenges in the clinical measurement of bone strength remain and will also evolve. The field of osteoporosis has grown with the use of DXA and will continue to embrace this technology as other technologies to measure fracture risk become applied in clinical practice.