The Potential Value of Dual-Energy X-Ray Absorptiometry in Orthopedics

Dual-energy X-ray absorptiometry (DXA) is a well-established technology with an important and well-known role in measuring bone mineral density (BMD) for the purpose of determining fracture risk, diagnosing osteoporosis, and monitoring treatment efficacy. However, aside from the assessment of bone status, DXA is likely underutilized in the field of orthopedics, and most orthopedists may not be aware of the full capabilities of DXA, particularly with regard to total body scans and body composition assessment. For example, DXA would be a valuable tool for monitoring body composition after surgery where compensatory changes in the affected limb may lead to right-left asymmetry (eg, tracking lean mass change after knee surgery), rehabilitation regimens for athletes, congenital and metabolic disorders that affect the musculoskeletal system, or monitoring sarcopenia and frailty in the elderly. Furthermore, preoperative and postoperative regional scans can track BMD changes during healing or alert surgeons to impending problems such as loss of periprosthetic bone, which could lead to implant failure. This article discusses the capabilities of DXA and how this technology could be better used to the advantage of the attending orthopedist.