Reliability of analysis of the bone mineral density of the second and fifth metatarsals using dual‐energy x‐ray absorptiometry (DXA)

Abstract

BackgroundMetatarsal fractures, especially of the fifth metatarsal, are common injuries of the foot in a young athletic population, but the risk factors for this injury are not well understood. Dual-energy x-ray absorptiometry (DXA) provides reliable measures of regional bone mineral density to predict fracture risk in the hip and lumbar spine. Recently, sub-regional metatarsal reliability was established in fresh cadaveric specimens and associated with ultimate fracture force. The purpose of this study was to assess the reliability of DXA bone mineral density measurements of sub-regions of the second and fifth metatarsals in a young, active population.MethodsThirty two recreationally active individuals participated in the study, and the bone density of the second (2MT) and fifth (5MT) metatarsals of each subject was measured using a Hologic QDR x-ray bone densitometer. Scans were analyzed separately by two raters, and regional bone mineral density, bone mineral content, and area measurements were calculated for the proximal, shaft, and distal regions of the bone. Intra-rater, inter-rater, and scan-rescan reliability were then determined for each region.ResultsProximal and shaft bone mineral density measurements of the second and fifth metatarsal were reliable. ICC’s were variable across regions and metatarsals, with the distal region being the poorest.ConclusionsBone mineral density measurements of the metatarsals may be a better indicator of fracture risk of the metatarsals than whole body measurements. A reliable method for measuring the regional bone mineral densities of the metatarsals was found. However, inter-rater reliability and scan-rescan reliability for the distal regions were poor. Future research should examine the relationship between DXA bone mineral density measurements and fracture risk at the metatarsals.

Micro‐CT analysis of the Lisfranc complex reveals higher bone mineral density in dorsal compared to plantar regions

“…These studies showed generally higher BMD in the dorsal, rather than plantar, regions of bone, 19,22 which is further supported by our results. Additionally, variation in DXA reliability reinforces the use of quantitating CT or micro‐CT for detailed bone density analysis 24 . Our study is novel in this arena because of the use of a calibration phantom to report BMD in calibrated HA units, as opposed to Hounsfield units.…”

“…Additionally, variation in DXA reliability reinforces the use of quantitating CT or micro-CT for detailed bone density analysis. 24 Our study is novel in this arena because of the use of a calibration phantom to report BMD in calibrated HA units, as opposed to Hounsfield units. Additionally, we use the same method to examine all four bones in the Lisfranc complex and use large subregions that are clinically relevant for understanding injury patterns and proper injury management, especially in unstable Lisfranc injuries.…”

“…Previous research on BMD in the Lisfranc complex is relatively limited. Existing studies have examined single bones or small complexes, such as the medial cuneiform, 17,18 first metatarsal, 19 second metatarsal, 20,21 or first tarso-metatarsal joint, 22 or have looked at larger regions but with a focus in inter-bone differences, 23,24 rather than looking at BMD differences between subregions of the same bone. Additionally, these studies have predominantly used clinical CT and/or DXA imaging, with only one study using micro-CT imaging, 18 and none of the existing literature has been done with a calibration phantom.…”

A Narrative Review of Metatarsal Bone Stress Injury in Athletic Populations: Etiology, Biomechanics, and Management

“…Ex vivo, aBMD explains ~80% of the variance in metatarsal fracture force 28 . Unfortunately, in vivo studies report low precision and accuracy for measuring metatarsal aBMD, thereby limiting clinical utility 29,30 …”

An investigation into the association of bone characteristics and body composition with stress fracture in athletes

“…Currently, whole body dual-energy x-ray absorptiometry (DXA) measurements are used as a method to assess an individual's risk of stress fracture injury [5]. lower bone mineral density (BMD), bone mineral content (BMC) and reduced bone structural properties have been associated with stress fracture risk in some athletic population (cricketers (lumbar spine BMD, [6]), runners (tibial strength, [7]; hip BMD, [8]), triathletes (tibial cortex; [9]) and female athletes (trabecular BMD; [10]), but not in others (endurance athletes (triathletes and runners-whole body, lumbar spine and hip) [11] and runners (whole body, lumbar spine, hip, radius) [12][13].…”