Computerized Evaluation of Abnormal Hand Bone Patterns in Skeletal Dysplasias Arkadiusz Gertych, Morgan Clond, Ralph Lachman, and David Rimoin Abstract. Assessment of bone disproportion is one of the routine radiological pro- cedures frequently performed at a skeletal dysplasia diagnosis center. The existing knowledge on skeletal dysplasia patterns is more qualitative than quantitative, and the commonly applied diagnostic procedure is the manual, atlas-based evaluation of radiographs (including the hand) by an expert. A computer-aided diagnosis pack- age (CAD) for bone age assessment was improved to analyze hand radiographs of skeletal dysplasia subjects with manifested hand bone abnormalities. The CAD soft- ware can automatically measure the lengths of phalangeal bones, compare them with those obtained from normal subjects collected in the Digital Hand Atlas (DHA), and recognize selected abnormality patterns. We have tested our method based on brachydactyly type A cases from the skeletal dysplasia diagnosis center that were matched with subjects from DHA in the age range of 2-12 years. New quantitative results obtained from this study have the potential to enrich the qualitative criteria currently utilized in the manual evaluation of abnormal bones, and thereby improve the performance of the diagnostic procedure. Arkadiusz Gertych Department of Surgery, Cedars-Sinai Medical Center, 8700 Beverly Blvd, Los Angeles, CA 90048 e-mail: gertycha@cshs.org Morgan Clond Cedars-Sinai Graduate Program in Biomedical Science and Translational Medicine, 8700 Beverly Blvd, Los Angeles, CA 90048 e-mail: Morgan.Clond@cshs.org Ralph Lachman International Skeletal Dysplasia Registry, Medical Genetics Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd. PACT 4, Los Angeles, CA 90048 David Rimoin Medical Genetics Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd. PACT 4, Los Angeles, CA 90048 E. Pi˛ etka and J. Kawa (Eds.): Information Technologies in Biomedicine, AISC 69, pp. 123–132. springerlink.com c  Springer-Verlag Berlin Heidelberg 2010