Osteoporosis: An X-Ray Imaging Diagnostic Challenge

Osteoporosis is a common condition in the adult population that is characterized by reduced bone density and changes in bone micro-architecture that lead to increased skeletal fragility. Individuals with osteoporosis are at a higher risk of traumatic fractures as well fragility fractures, which occur either without trauma or with minimal impact. The National Osteoporosis Foundation estimates that up to 52 million Americans may suffer from osteoporosis; but in spite of this fact, the condition remains underdiagnosed and undertreated. Risk factors for osteoporosis include age, low body weight, positive history of smoking, heavy alcohol use, a personal history of previous fractures, and a family history of fractures.

Screening the population for osteoporosis with x-ray systems is important because numerous effective treatment modalities exist. Simple measures such as regular weight-bearing exercise are thought to improve bone density. Calcium supplements with vitamin D may stabilize bone density over time. Bisphosphonates such as alendronate and risendronate have been shown by multiple studies to improve bone density at the hip and lumbar spine. Certain bisphosphonates have also been shown to lower the risk of fragility fractures in patients with osteoporosis, while newer medications such as raloxifene have also proven effective in improving bone density.

In spite of the availability of effective treatment, x-ray imaging screening remains a challenge for physicians and patients alike. A number of professional organizations including the National Osteoporosis Foundation and the US Preventive Services Task Force recommend screening all women over 65 for osteoporosis. Other professional organizations recommend screening women under 65 with risk factors and men over 70 as well. Dual energy x-ray absorptiometry, also known as the DEXA Scan, has been the standard method for bone density testing for the last two decades. While DEXA scans are highly sensitive and specific for osteoporosis, there are several negative aspects of DEXA that have limited its availability. DEXA scanners are large and expensive; with prices as high as $80,000 and a full room space required to accommodate a DEXA scanner, it is logistically impossible for most primary care offices to offer DEXA in-house. Patients generally must be referred to tertiary facilities, which limits patient interest in screening and decreases compliance. DEXA scanners lack portability and are therefore often unavailable to patients in underserved healthcare areas and third world countries. DEXA also exposes patients to a small amount of ionizing radiation.

Dicom’s Metriscan x-ray scanner is a portable bone densitometer that has been specially designed to make osteoporosis screening more widely available to patients and physicians. The Metriscan is compact, highly portable, and affordable in comparison to traditional DEXA scanners; it provides primary care offices with the ability to perform bone density testing in-house. The Metriscan x ray system is engineered with ALARA philosophy in mind so that patients are exposed to lower doses of ionizing radiation compared with other methods of bone density measurement. Using advanced technology, this device accurately measures the bone density in a patient’s hand. With its portability and relatively low cost, this x-ray imaging device is an innovative technological development that has the capacity to make osteoporosis screening more widely available in primary care offices, in underserved areas, and potentially even in third world nations.