Medical Data Required

Images 1) We are looking for single X-Rays of full legs of patients below 18 years (pediatric images) in the AP-view 1.1) Although we use single full-leg images, we are aware that most images are stitched and come as a series of up to four images (hip, knee, ankle, stitched full leg). In such a case we would consent to take the whole series and perform the filtering ourselves. 1.2) The X Rays should be standing, full-leg (hip, knee, ankle visible) in the AP (frontal) view 1.3) The original images should be CR or DX images, so that the pixel-spacing is reliable and is in the range between 0.1 and 0.4 px / micro-meter 1.4) The images should preferably show a calibration device (sphere, ruler, etc) 1.5) The images should preferably be bi-lateral 1.6) The images come preferably from three or more sites 1.7) All femur and tibia/fibula bone contours must be fully and clearly visible Population 2) Patients below the age of 18 years who have had the XRay for the purpose of leg-length discrepancy measurements or related indications 2.1) the age range of the final dataset should cover as wide an age range as possible, while being as uniformly distributed as possible over the age range (say we have ten age-range bins, there should be an equal number of images in each range) 2.2) We are looking for a random sample of images, but would prefer a dataset enriched with mild and severe deformities 2.3) The population should be a random sample of the US population and should cover as many ethnicities as feasible