Fully automated radiogrammetric measurement of third metacarpal bone from hand radiograph

Osteoporosis is a disease caused by reduction of bone mass, bone strength and deterioration of bone structure. The gold standard method for diagnosis of osteoporosis is measurement of bone mineral density (BMD) using Dual X-ray Absorptiometry (DXA). However, DXA is expensive and not widely available in developing countries. An alternative cost-effective method for measurement of bone loss and strength is metacarpal radiogrammetry, by which geometric measurements of cortical bone of the metacarpal bone are measured. In this paper, we propose a fully automated method for segmentation of third metacarpal bone from hand radiograph and radiogrammetric measurements using mathematical morphology. Cortical width and thickness are measured from the endosteal and periosteal edges of the metacarpal bone using which bone indices which help in diagnosis of osteoporosis can be computed. The proposed segmentation method was tested on 157 hand X-ray images. A success rate of 94.9% is obtained for automatic detection of third metacarpal bone. Evaluation of cortical measurements of 3 calibrated images is done by comparing the results with ground truth. The mean accuracy error obtained was 0.02cm and 0.04cm for cortical width and medullary width, respectively.