The recommended laboratory test is the management of total urinary hydroxylysyl pyridinoline and lysyl pyridinoline cross links after kydrolysis by HPLC, a test which is readily available and has a very high degree of sensitivity and specificity [Steinmann et al., 1995]. The determination of dermal hydroxylsine is also easy; however determination of lysyl hydroxylase activity in fibroblasts and/or mutational analysis of the PLOD gene is performed on a research basis only.