Automated femoral measurement in total hip replacement radiographs

Loosening of the prosthesis components is the most common long term problem following total hip replacement (THR) and is difficult to treat successfully. We have developed a reliable and accurate method of automatically segmenting, classifying and measuring the femoral components of cemented THR. Our method combines three separate techniques to classify, different sections of the model from standard clinical radiographs. Reference axes are defined and magnification corrections made allowing extracted measurements to be compared within and between patients giving quantified measurements of bone thickness, cement radio-lucency and prosthesis positioning.