Intramedullary nailing is often the treatment of choice in the management of fractures in the tibial diaphysis. With the advent of interlocking nailing, the indication for nailing have expanded, recently. One of the most frequent but little discussed complication of tibial nailing is fracture malalignment leading to angular or rotational deformities. This retrospective study was undertaken to access the incidence of aneular malalignment after interlocking nailing for 210 tibiae(208 patients). The results obtained were as follows;

1. The incidence of angular malalignment was 12.4%

2. The incidence of angular malalignment was 15.8% in proximal one third, 4.1% in middle one third,20.7% in distal one third fractures.

3. The most frequent deformity was valgus angulation in distal one third fractures.

4. Angular deformity was developed more frequently in cases of unlearned nailing(18.9%) than reamed nailing(8.4%).

5. Angular deformity was developed more frequently in cases of double level fracture(22.2%) than single level fracture(11.5%).