A CADAVER MODEL OF FEMORAL INTRAMEDULLARY REAMING PRESSURES DEMONSTRATES REDUCED PRESSURES WITH SINGLE PASS IRRIGATED REAMER

Abstract

The purpose of our study was to compare the performance of a new intramedullary reaming device to a contemporary reaming system. The new intramedullary reaming device was the Synthes Reamer/Irrigator/Aspirator reamer (RIA) which differs from contemporary reaming devices in that it has a built-in irrigation and aspiration system to reduce the intramedullary pressures and temperatures associated with reaming. An in-vivo cadaver model was developed to quantify intramedullary pressure, temperature, speed and force of reaming. The results showed significant differences in intramedullary pressures with no significant differences in speed and force of reaming.

The purpose of our study was to compare the performance of a new intramedullary reaming device to a contemporary reaming system.

The Synthes Reamer/Irrigator/Aspirator reamer (RIA) produced significantly lower peak and average intramedullary pressures during reaming with no significant differences in speed and force of reaming.

A reaming system with a built-in irrigation/aspiration could possibly reduce the morbidity and mortality associated with the reaming of long bone fractures. There were significantly lower minimum, maximum and average proximal and distal intramedullary pressures with the RIA reamer. There were no significant differences in force or speed of reaming. No temperature changes were noted with either reaming system.

A cadaveric model was developed to compare the RIA reaming system to a contemporary reaming system. Pressures were measured with pressure transducers inserted proximally and distally. Temperatures were measured with thermocouples inserted adjacent to isthmus. Force of reaming was measured with a load cell distally. Speed was calculated from data collected from a linear voltage displacement transducer. Fifteen, matched pairs of frozen, unpreserved femurs were reamed using both reaming systems and the data collected. Canals were reamed to a diameter two centimeters greater than the templated canal size. Data was collected and analyzed with paired t-tests (p< .05).

Embolic material within the cardiovascular system has been shown to increase morbidity and mortality in susceptible individuals. Embolization is related to increased intramedullary pressures. The RIA reamer, as a result of its built-in irrigation/aspiration capacity, produces lower intramedullary pressures. This may have clinical significance.

Funding: This work was supported by Synthes (West Chester, PA)