The Early Effects of Intramedullary Reaming of the Femur on Bone Mineral Density; an Experimental Study in Pigs

Background and Aims: Both fracture and fracture treatment affect bone mineral density (BMD). BMD after standard intramedullary reaming of the femoral cavity and after reaming with a reamer-irrigator-aspirator (RIA) system were studied with the hypothesis that the RIA technique would lead to lower BMD levels. Material and Methods: Dual-energy X-ray absorptiometry (DXA) was performed on the third day after operation with standard intramedullary nailing technique (n = 6)or RIA technique (n = 7) in intact femora of young Norwegian landrace pigs. Results and conclusion: Significantly lower BMD were found in the mid-shaft and total femur after reaming with the RIA technique compared to the non-operated femur. Traditional reaming technique resulted in significantly higher BMD in the distal femur. Interpretation: The results of this study indicate that standard reaming increased BMD in the distal femur, suggesting compressive effects on trabecular bone. The RIA technique decreased BMD in the femoral diaphysis and total femur, suggesting removal of trabecular bone. A possible clinical impact of the findings remains to be investigated.