Anterior knee pain following intramedullary nailing of tibial shaft fractures: does bony portal point in the sagittal plane affect the outcome?

Forty-four consecutive diaphyseal extra-articular tibial fractures (43 patients) were treated with intramedullary interlocking nail. There were 35 men and eight women with a mean age of 38 years. Average follow-up was 25 months. Cases were divided into two groups: anterior-knee-pain group, 20 knees; and no-pain group, 24 knees. The lateral projection radiographs of their tibiae were scrutinised for precise bony portal point. The distance between articular surface and tibial tubercle was divided into three equal zones. In the superior zone, six had pain and six did not. In the central zone, eight had pain and 15 did not. In the inferior zone, six had pain and three did not. There was no significant difference between anterior knee pain and the three zones of the bony entry, age, gender, mechanism of injury, dynamisation, nail protrusion, approach and union time. We conclude that bony entry point in the sagittal plane is not a significant prognostic indicator for anterior knee pain following intramedullary tibial nailing.