Dynamisation and early weight-bearing in tibial reamed intramedullary nailing: its safety and effect on fracture union.

Aim: To compare the safety and effect on tibial diaphyseal fracture bone union of two intramedullary nailing techniques: (1) dynamic locking with early, full weight bearing, and (2) static locking with delayed weight bearing until bone union.

Patients And Methods: This is a retrospective case-control study of closed or type I open tibial diaphyseal fractures (types A and B according to the AO classification) treated with dynamic nailing (32 cases) or static nailing (35 cases). The type of intramedullary nail, the surgical technique and the postoperative protocol were similar for both groups, with the exception of the locking mode and the time of weight bearing. Time to union, mechanical and biological complications, and the number and type of re-operations needed until union were recorded and analysed.

Results: Mean union time was 21 weeks in the dynamic group and 26 in the static group (p = 0.051). In both groups 3 cases of nonunion were noted. In the dynamic group there was 1 case of delayed union and 1 case of malunion. In the static group, 5 cases of delayed union and 5 cases of malunion were found. Four reoperations were required in the dynamic group, whereas 10 were needed in the static group (p >0.05). Initial degree of interfragmentary gaps had an impact on the mean time to union and the appearance of biological complications in both groups.

Conclusion: Dynamic nailing assembly in intramedullary nailing in closed or type I open tibial diaphyseal fractures with limited comminution (types A and B according to the AO classification) is safe when used for these fracture types. A dynamic mode of nailing should be encouraged in these fracture patterns.