Thoracic force-deflection studies in living and embalmed primates.

In order to evaluate the validity of the use of the cadaver in making estimates of the living human response to cardio-thotacic impact a series of tests were performed under similar conditions comparing the force-deflection response of the anaesthetized and the embalmed Rhesus monkey. Twelve primates (100 tests) were subjected to controlled thoracic impact with a Remington Humane Stunner while seated in a sled held firmly in place. Tests on 8 of the monkeys were performed while they were anaesthetized and again 30 days after being embalmed. Four monkeys were tested only after embalming. X-rays were used to evaluate rib fractures. Results showed clear significant differences between anaesthetized primates and those tested 30 days after being embalmed. Forces developed under the same test conditions were I32 per cent higher for the embalmed primates compared to anaesthetized monkeys under static test conditions at maximum displacement and 25-50 per cent higher under dynamic testing conditions for all but the initial part of the tests. The results of these studies indicate that the mechanical characteristics of the primate thorax are dramatically affected by death and/ or subsequent embalming procedures.