QUESTION What about the knowledge of specific orthopaedic subjects in medical education as tested with mc-questions and open-ended questions? METHOD 524 medical students were evaluated by a questionnaire survey to determine the state of orthopaedic knowledge in different periods of medical education. With the same questionnaire the use of two different types of written tests of knowledge (multiple choice questions and open-ended questions) has been tested and the results have been compared. The students participating in the orthopaedical practical (6th clinical semester) have been tested before and after the practical, given as pretest and posttest. RESULTS The results show that the orthopaedic knowledge corresponds to the educational level so that during medical formation, there is a gradual knowledge gain. Comparison of the results of the pretest and the posttest reveals that the highest knowledge gain occurred during the orthopaedic practical. For all groups candidates performed better in mc-questions than in open-ended questions. Likewise in all groups, open-ended questions were found to be more difficult than the mc-questions. CONCLUSIONS To summarize it may be concluded that there is a gradual orthopaedical knowledge gain during medical formation. It was found that students gain a considerable part of their technical knowledge during the practicals. Both mc-questions and open-ended questions are useful to measure this knowledge gain where there are hints that open-ended questions give a more accurate assessment of the actual knowledge. The pre- and posttest setting can provide both teachers and students with feedback regarding the realization and acquisition of instructional contents.