The creation and implementation of new methods and means of local treatment of wounds occurs in stages, however, a number of difficulties arise at each stage. The article discusses one of the main problems that arise at the preclinical stage when modeling deep defects of the skin and articular cartilage – the difficulty of accurately reproducing full-layer defects of the skin and articular tissue. Various factors influencing the success of such modeling also investigated, including the type of animal, the size of the defect and its location.