Stability of reamed and unreamed intramedullary tibial nails: a biomechanical study

We examined the correlation of bone mineral density and bone strength in the cadaver tibia, and looked in vitro at the relative stability of tibial fractures fixed with either reamed or unreamed tibial nails. Bone-mineral density correlated well with bone strength (r = 0.946), but paired tibias did not correlate closely. The unreamed nail-bone construct was less stable than the reamed construct in each pair tested (P < 0.05), and a comparison of all bones showed it to be less stable at all levels of our testing regimen, including failure (P < 0.01). Bending and breakage was seen in four of the smaller unreamed interlocking screws (4 mm).