Lateral tibial bone mineral density around the level of the proximal tibiofibular joint.

Purpose: During open-wedge high tibial osteotomy, fracture occurring in the insufficient osteotomy before distraction of the osteotomy gap is an important complication. The objective of this study was to evaluate bone mineral density (BMD) around the proximal tibiofibular joint (PTFJ) and the osteotomy hinge. The hypotheses of this study were (1) BMD would be higher in the level of PTFJ, compared with that of above--or below--the level of PTFJ, (2) BMD of the posterolateral side of the hinge would be higher than that of the anterior or lateral side.

Methods: Computed tomography was used to determine the BMD of the lateral aspect of the proximal tibia around the PTFJ and the osteotomy hinge. The means and standard deviations of the regions of interest were measured. To verify the first hypothesis, a coronal reconstructed image showing the beginning of the fibula head was used and an axial reconstructed image showing the beginning of the fibula head was used for verification of the second hypothesis.

Results: BMD of the lateral aspect of the proximal tibia at the level of the PTFJ was significantly higher, compared with that of above (P = 0.04)-or below (P < 0.01)--the level of the PTFJ in male patients. In addition, it was also significantly higher, compared with that of below the level of the PTFJ (P < 0.01). BMD of the posterolateral area of the proximal tibia was significantly higher than that of the anterior or lateral area in both male and female patients (P < 0.01).

Conclusion: BMD of the level of the PTFJ was higher, compared with that of above-or below-the level of the PTFJ and that of the posterolateral area of the proximal tibia was significantly higher, compared with that of the anterior or lateral area.