<p>As in the case of surgical orthopedic implants, the increased life expectancy and the higher risk of accidents, thus rendering a higher frequency of surgeries, have led to an increased use of surgical instruments. The aim of this work is a failure analysis of punches for cervical surgery and an attempt of correlating them with microstructural characteristics of the martensitic stainless steels used in their fabrication. Techniques such as optical microscopy, scanning electron microscopy (SEM), hardness and corrosion resistance tests (boiling water, thermal exposure, copper sulfate aqueous solution and in autoclave) were employed. The results obtained in this study allowed the identification of the causes of the failure, mainly related to a significant number of voids, some of them placed on grain boundaries, as well as a dendritic segregation, thus rendering an embrittling condition for this material. Furthermore, this material is harder than expected for this type of application, probably due to inadequate heat treatment conditions. This excessive hardness can be unfavorable, since usually harder materials are also more brittle. The samples were considered approved in all corrosion tests performed, thus indicating that corrosion was not a key factor for failure, more probably related to casting defects and inadequate heat treatment.</p>