 In archaeology, our study is essentially based on a skeleton from which we try to reach the corpse and how it was buried. In the context of a PhD entitled the Decay of the Corpse and Funeral Practices of the Population of the Past comparison between forensic and archaeological data, I had the opportunity to make observations on corpse undergoing decomposition of this approach to the question of the restitution of burial practices from the corpse to the skeleton and thus study the decomposition process and its role in the constitution of the archaeological image. So I studied 50 burials from the 19th and 20th century from two sites, Châtelet in Belgium with 15 burials realized between 1870 and 1963, and 35 individuals from exhumation from a contemporary Swiss cemetery, CSE. In both cases I worked on the photographic documentation produced during the exhumation. For Châtelet several general and detailed photographs were taken but at CSE we had only one general and non-zibitoid photograph of the burial. At CSE the burials are more recent and they are realized between 1985 and 1987. In Châtelet the individuals are buried in zinc coffin which are placed in cellar in a 14 case and the last one is buried in the ground at the depth of two meters in the clay soil. The deceased are buried dressed and those devices are sometimes remarkably well preserved such as a man dressed in a suit here on your left and a woman dressed in a yellow shawl and warped wrapped in a blanket on your right. At CSE the individuals are also buried in zinc coffins most of which are completed with synthetic weather proofing clothes like this, installed inside the casket to prevent the dispersion of the products of the composition. All individuals are buried in the clay soil at the depth of two meters. The clothing is generally less well preserved than in Châtelet however in some cases identification was possible like for example on your left a man buried in a religious abit and on the right a subject dressed in a shirt that is still very well preserved. Beyond a good theoretical knowledge of the decomposition process I made systematic and detailed observations of all anatomical segments in order to understand and characterize the evolution of the decomposition in context of a burial and particularly in the zinc coffin. From an archaeological perspective I have also paid particular attention to the logic of joint dislocation in order to provide additional details to those already acquired but which remain mainly based on archaeological examples. Finally I studied 50 archaeological burials mainly from the medieval and modern period to evaluate how those information from the recent burials can be applied in archaeological context. Dinker position is a variable phenomenon that can result in the disappearance of soft tissues, the petrification of the conservation over a more or less long period of soft tissue which is the mummification and saponification which are transformations of the corpse. Those evolutions are not necessarily independent of each other and can be perfectly in tune with each other. However in our archaeological reasoning in the absence of our organic remains there is very little attention paid to mummification or saponification. In more detail our observations reveal that petrification in a casket results in the liquefaction of soft tissues that are attracted to the bottom of the casket. However it's not an homogenous process and is closely related to the arrangement of soft tissue around the bones. For example the tibia which is on the anterior and medial position of the leg and creates earlier exposure than the femorisory which is covered by a greater quantity of soft tissues. As a result soft tissue degradation and both exposure doesn't occur in the same way in different anatomical segments. In addition the accumulation of decomposition products particularly in the pelvis which naturally forms a ball can allow the preservation of small bones or objects such as deads of rotary for example. Archaeologically this hypothesis could have been considered in different cases such as here for example where the bones are their right hand. Left hand sorry I can't kill sometimes. Normally they would have seen downstream their conservation despite the initial context of empty space is probably related to the accumulation of decomposition products but we'll see that it's a little bit more complicated in fact. The recognition of mummification on corpses let me to ask the question of its restitution in an archaeological context as the example shows the wrist and the hand which allow to be liable connections have remained connected despite the displacement of this block toward the elbow. This phenomenon is most likely related to a temporary mummification of the hand. The member elevated in the front of the abdomen slipped toward the elbow probably guided by a sleeve. Our observations could thus confirm the phenomena of dislocation in parodexical order by Bruno Morey and Pascal Sely. On the other hand we were unable to intensify osteoarcheological arguments that would allow to propose a simplification hypothesis in archaeological context nevertheless the discovery of white crusty residues which is actually dry adipose led me to propose this hypothesis in particularly for this case. Closing is also a factor not to be neglected because it creates specific spaces especially at the level and can therefore contribute to differential degradation. By participating in the absorption of liquids clothing can promote mummification as in this case for example the socks that play a major role in the drying of soft tissue. In archaeological context closing the recognition of constrained effect from the shoulder to the pelvis for these individuals shows here a very narrow and persistent habit or wrapping or both of them until the skeletonization of the disease since it impacts on the final arrangement of bones. On the left the preservation of food connection despite the decomposition into empty space is also a relevant argument for considering the presence of shoes however as shown by the right foot we have small dislocation that can occur particularly when the dorsal part of the food comes up against the shoes. Frequently it may be more difficult let's play with this example as we suppose for the left hand the preservation of the small bones on the hip bones can be linked to the produce of decomposition but what about his right hand as the example from the game which collection shows when the end are on clothing it can help the connection can be preserved even if in the coffin and so in empty spaces so for this archaeological example so far this archaeological example if we initially consider an impact of decay process in the preservation of the connection for the left hand we have also take in account the presence of clothing even if we cannot distinguish the exact role of each parameter. The repetitiveness of the observations made the current consideration of the variability of the decomposition process showed that the joint dislocation is a variable phenomenon that is closely related to the position of the disease the manner in which he is buried and therefore the manner he decomposes. Here for example we know that the left hand is completely dislocated in the first case while in the second case the cover wrapped around the head which allows the connection to be preserved in spite of the decomposition into an empty space. The various observations made during about this those exhumation provide information on the liability and the persistence of certain connections. I would like to illustrate this point with the example of the forearm and the wrist. At the wrist and the forearm observation revealed that the joint between the radius and the ulna is more labile at the distal end than at the proximal joint. This hypothesis is supported by the distribution of the ligament. The oblique cord is more persistent in the third in the proximal third on the on the one hand and on the other hand the annular ligament on the proximal extremity of the radius is also particularly a strong ligament. It's from a biomechanical point of view but it's not the only argument I think. For the wrist the relationship between the cup and the radius is more persistent than with the when with the ulna. Again anatomically this hypothesis is supported by a larger articulate surface at the radius at the presence of the articular capsule and more and more homogeneous distribution of ligaments. On the other hand the ulna is somehow rusted into the wrist which probably contributes to the liability of this connection with respect to the radius. In conclusion the study of exhumation of recent graves and those observations made on decomposing corpse provides a reliable and relevant support to overcome the impossibility of carrying out experiments on human bodies. My work thus highlights that this type of approach and on a larger scale the study of decomposition corpse is probably the best way to understand the logic of joint dislocation and thus advance our reasoning in the reconstruction of funeral practices of past populations. Thank you very much.