BONE PLATE FIXATION - AN EVALUATION OF INTERFACE CONTACT AREA AND FORCE OF THE DYNAMIC COMPRESSION PLATE (DCP) AND THE LIMITED CONTACT DYNAMIC COMPRESSION PLATE (LC-DCP) APPLIED TO CADAVERIC BONE

Objectives: To determine the effects of bone morphology on the interfa cial mechanics of bone plate fixation. Design: A comparison of two bon e plate designs using measures of contact area and force in three cond itions of bone type. Intervention: The influence of bone plate design, bone type, and implant location on interfacial characteristics of con tact area and average force were evaluated using pressure-sensitive fi lm in cadaveric bone. Data were quantitated using computer-assisted im age analysis. Main Outcome Measurements: Means of the two dependent va riables in each of the three conditions were compared using analysis o f variance. Results: In human femora and equine third metacarpi, there were no apparent differences in interface contact area attributed to bone plate design, although there were significant differences for int erface contact force. In humeri, significant differences in both inter face contact area and force were found between bone plate designs. Con clusions: Results show that bone surface topography and implant locati on are major determinants of the interfacial elements of contact area and average force between a plate and the bone to which it is applied.