CR images of metacarpel cortical edge detection-bone profile histogram approximation method

The conventional criterion for fracture risk assessment is measured based on bone mineral density (BMD). These are measured using bone densitometry machines. Although there is a strong association between bone strength and BMD, it cannot sufficiently predict fracture risk in osteoperotic patients. In view of this a more accurate measurement of bone strength is required. Bone strength are measured by geometric measurement of the bone cortical area. Cortical thickness can be measured by finding the edges of the endosteal and the periosteal of the cortical bone. Image segmentation methods could be used to find these edges. This paper presents a method of finding these edges from the radiograph of non-dominant hand. Measurements are made from metacarpal two, three and four. The edge detection module developed is based on bone profile histogram approximation algorithm. However better cortical outline can only be obtained after preprocessing the images with smoothing filters. Evaluation is done by comparing the measurements of the inner and outer cortical diameter obtained from the processed images with manual measurements using mirocalipers.