The aim of this paper is to evaluate the elasticity modulus of fresh human cancellous bone from the internal and external compartments segments of osteoarthritic and non-osteoarthritic knees. Cancellous bone samples of young and old subjects from both genders were collected. The measurements of the elasticity modulus were made only few hours after the samples were taken in through compression tests. The results show that the average value of elasticity modulus of the internal compartment (IC) (84.92 MPa) was the double of the external one (EC) (40.12 MPa). These values were found regardless of the gender and age factors. In osteoarthritic knees only the values of the internal compartment (121.88 MPa) increased, without significant variation of those of the external compartment (42.91 MPa). The results of this work need to be confirmed by other series. If they are validated, they would explain that the preferential site of osteoarthritis on the inner compartment of the knees is not only due to a static disorder, but that there is a structural bone factor. The confirmation of this new parameter will invite us to a review our anatomical, physiological, biomechanical knowledge of cancellous bone. The study was approved by the ethics Committee of Rabta Tunis Hospital, and all participants provided informed consent indicating their conscious and voluntary participation.