Article

Computer modelling of the heat flow in surgical cement during endoprosthesoplasty

Journal of Achievements in Materials and Manufacturing Engineering 01/2007;
Source: DOAJ

ABSTRACT Purpose: The problem of the modelling of the surgical cement behaviour during implantation has beenpresented in the paper. The purpose was to find the proper model describing the temperature fields in the boneduring the surgery treatment.Design/methodology/approach: Computer modelling has been used to predict the temperature influence on thebone tissue during polymerization process.Findings: During orthopaedic surgical procedures with the use of methyl polymethacrylate surgical cements, thetemperature sometimes reaches 80°, which causes atrophy of the bone tissue. The process occurs locally, sinceit depends on both the amount of polymerization heat generated during the reaction and on the heat exchangeconditions at cement-bone tissue and bone cement – implant boundaries. Striving to better understand theabove-mentioned phenomena through a model approach, models were developed under the study to calculatetemperature distributions in the bone and in implant components during the procedure of endoprosthesis stemimplantation. Calculations were made for different cement layer thickness variants and for different amountof cement concentrated around the top of the stem. The characteristics of temperature changes with time indifferent points of the bone and cement have been determined and temperature distributions in bone and cementfor selected instants of time have been worked out.Practical implications: The analysis carried out makes it possible to determine the location of areas mostthreatened with an adverse effect of an elevated temperature. In each case, they are located in the vicinity ofthe top of the endoprosthesis stem. These conclusion together with obtained data should be important for thesurgeons during surgical operation..Originality/value: The work presents the own method of heat flow modelling during the polymerization of surgicalcements. The results of the own method of the heat source characteristic description has been shown as well.

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